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The paper discusses the research and methodological aspects of introducing the new term "catafluvial deposits" into genetic classification of Quaternary deposits. For this purpose, fieldwork was carried out aimed at studying terrace complexes within the Yaloman-Katun zone of Gorny Altai, which has recently become a unique natural laboratory for investigating hypothetical glacial superfloods. Based on original materials and data from other areas with similar geological and physico-geographical conditions, it is concluded that the introduction of a separate genetic type "catafluvial" is currently premature. [ABSTRACT FROM AUTHOR]

Shear zones are strain localization structures whose geometry and kinematics control the way how large crustal blocks are disposed and also provide important insights into the nature of pathways and deposition of ore forming fluids. Detailed geological field mapping, consolidated with meso- and micro-structural investigations, flow kinematics and finite strain analyses are fundamental tools to obtain information about the same. Formation, transport and precipitation of gold in major shear zone type gold deposits of the world, are also controlled by shearing activities. The Ramagiri-Penakacherla transcratonic shear zone system is characterized by NW-SE trending, 0.5 to 1 km wide shear zone, affecting both the Ramagiri-Penakacherla schist belt (RPSB) and surrounding granitoids. Sense of shearing is dominantly dextral and the main shear sense indicators include S-C fabric, down-dip stretching lineation, rotated quartz and feldspar porphyroclasts, drag folds, delta and sigma quartz porphyroclasts, bilaterally stretched quartz and feldspar porphyroclasts, and pinch-and-swell structures. Detailed kinematic and strain analyses were combined with vorticity estimates on rocks from these zone to document the patterns and geometry of deformation. The strain parameter measurements including strain ratio in the XZ principal plane of strain ellipsoid (RXZ), strain ellipsoid shape (K) and strain intensity (D) highlight a flattening strain shape of the strain ellipsoid. The shear zone is divided into three zones from its boundary to the center, depending on the amount of matrix and clast size viz. protomylonite, mesomylonite and ultramylonite. The quantitative kinematic analyses highlight that Wm varies between 0.774 to 0.89 for the protomylonite, 0.756 to 0.85 for the mesomylonite and 0.635 to 0.83 for the ultramylonite. This, in turn, indicate considerable proportion of pure shear, varying from 30% to 43% for the protomylonite, 35% to 45% for the mesomylonite and 38% to 56% for the ultramylonite (shear boundary to the center). Identification of pure shear component helped in explaining the varying width of the schist belt, along with its disappearance at punctuated intervals. Heterogeneous distribution of gold deposits in the RPSB is explained by better connectivity of the shear fractures in the mesomylonite and protomylonite zone (near the shear zone boundary) with lower strain than the ultramylonite zone (center of the shear zone), which facilitated better permeability for gold-bearing fluid pathways to flow and ultimate deposition. [ABSTRACT FROM AUTHOR]

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Prospectivity mapping based on deep learning typically requires substantial amounts of geological feature information from known mineral deposits. Due to the limited spatial distribution of ore deposits, the training of predictive models is often hampered by insufficient positive samples. Meanwhile, data-driven mineral prospectivity mapping often overlooks domain knowledge and expert experience, leading to poor interpretability of predictive results. To address this problem, we employed the Gaussian mixture model (GMM) for spatial feature classification to expand the number of positive samples. The approach integrated the embedding of geological map knowledge graphs with geological exploration data to enhance the knowledge constraints of the prospecting model, which enabled the integration of knowledge with data. Considering the complex spatial structure of geological elements, a bi-branch utilizing the 1-dimensional convolutional neural network (CNN1D) and graph convolutional network (GCN) was used to extract geological spatial features for model training and prediction. To validate the effectiveness of the method, a gold mineralization prediction study was conducted in the Wulonggou area (Qinghai province, western China). The results indicate that, when the number of GMM spatial feature classifications was 17, the positive-to-negative sample ratio was optimal, and the embedding of the knowledge graph controlled the prediction area distribution effectively, which demonstrated strong consistency between the prospecting area and the known mineral deposits. Compared with the predictions by CNN1D, the fused prediction model of CNN1D and GCN yielded higher accuracy. Our model identified 11 classes of mineralization potential areas and provides geological interpretations for different prediction categories. [ABSTRACT FROM AUTHOR]

Supervised machine learning methods for geological mapping via remote sensing face limitations due to the scarcity of accurately labelled training data that can be addressed by unsupervised learning, such as dimensionality reduction and clustering. Dimensionality reduction methods have the potential to play a crucial role in improving the accuracy of geological maps. Although conventional dimensionality reduction methods may struggle with nonlinear data, unsupervised deep learning models such as autoencoders can model non-linear relationships. Stacked autoencoders feature multiple interconnected layers to capture hierarchical data representations useful for remote sensing data. We present an unsupervised machine learning-based framework for processing remote sensing data using stacked autoencoders for dimensionality reduction and k -means clustering for mapping geological units. We use Landsat 8, ASTER, and Sentinel-2 datasets to evaluate the framework for geological mapping of the Mutawintji region in Western New South Wales, Australia. We also compare stacked autoencoders with principal component analysis (PCA) and canonical autoencoders. Our results reveal that the framework produces accurate and interpretable geological maps, efficiently discriminating rock units. The results reveal that the combination of stacked autoencoders with Sentinel-2 data yields the best performance accuracy when compared to other combinations. We find that stacked autoencoders enable better extraction of complex and hierarchical representation of the input data when compared to canonical autoencoders and PCA. We also find that the generated maps align with prior geological knowledge of the study area while providing novel insights into geological structures. [ABSTRACT FROM AUTHOR]

Small island communities often rely on groundwater as their primary source of fresh water. However, the limited land area and high proportion of coastal zones pose unique challenges to groundwater management. A detailed understanding of the subsurface structure can provide valuable insights into aquifer structure, groundwater vulnerability, saltwater intrusion, and the location of water resources. These insights can guide groundwater management strategies, for example, pollution regulation, promotion of sustainable agriculture, establishment of coastal buffer zones, and re‐naturalization of land cover. Ordinarily, structural characterization relies on geological mapping and boreholes, however, such approaches can have insufficient spatial resolution to aid groundwater management. In this study, transient electromagnetic (TEM) methods are used to map the subsurface of a small, 13.2 km2, Danish Island. The approach successfully identified two previously unknown paleochannels, where the interface between Quaternary aquifer units and an underlying Paleogene Clay aquiclude had maximum depths of 100 and 160 m below sea level. Before this, the interface was assumed to be 15 to 25 m below sea level: therefore, these paleochannels present substantial potential groundwater resources. Resolving geological heterogeneity within the Quaternary deposits was less successful and future work will focus on addressing these limitations. Nonetheless, in several locations, evidence of saltwater intrusion was observed within the Quaternary units. This work demonstrates how TEM mapping can identify water resources, define aquifer boundaries, and aid water management decisions. Such approaches could be applied in other areas, particularly small islands, where similar groundwater challenges exist. [ABSTRACT FROM AUTHOR]

Deep-Seated Gravitational Slope Deformations (DSGSDs) are common in many geological environments, and due to their common limited displacement rate, they can remain unrecognized for a long time. Among the most significant events in Sicily is the Mt. San Calogero DSGSD. To contribute to a better understanding of its characteristics, including the geologic setting promoting its development, ongoing kinematics, and mechanism, a specific analysis was completed. In this paper, the results of this analysis, based on a three-folded strategy, are provided and interpreted in the context of DSGSD predisposing conditions and controlling factors. Especially, field observations associated to visual interpretation of aerial imagery were used for the identification and mapping of main geological features and landforms, high-resolution X-Band DInSAR data enabled researchers to fully characterize the deformational behavior of the slope, while a reduced complexity slope stability analysis allowed them to reconstruct the deep geometry of the DSGSD. Results from the analysis indicate that the DSGSD of Mt. San Calogero is composed of three blocks corresponding to fault-bounded tectonic elements and characterized by a specific kinematics and sensitivity to external forcing (i.e., rainfall), multiple landslides are associated to the DSGSD in the area and the deep geometry of the DSGSD is concave upward and resemble the characteristics of a rotational slide. The interpretation of the results suggests that the formation and the deformation of the Mt. San Calogero DSGSD are linked with the local and regional fault systems related to the Sicilian orogen, while shallow landslides are triggered, in clayey terrains, mostly by rainfalls. In addition, the integrated approach reveals that active tectonics and rainfalls in the San Calogero massive relief are the main driving forces of its different deformation behavior. [ABSTRACT FROM AUTHOR]

This study is based on the coupling of geological field data with geophysical studies in the geological mapping of the Central Domain of the Mbere Division (Adamawa-Cameroon). The first step was to calculate the residual grid associated with the geophysical data that will be used for the mapping of the basement. The second step before mapping consisted in calculating the analytical signal associated with the residual grid, used to interpret the geological formations under cover or in intrusion. Subsequently, a geological mapping approach based on the categorisation of geophysical signatures into ranges using the Encom Discover program was adopted. This approach is based on the analysis of the relief of geophysical anomalies. The process of categorisation which is done iteratively, takes into consideration in the same georeferenced space, the resolution of the input data, the variation of the field considered and the structural model previously interpreted. The result of the categorisation is then compared to the spatial distribution of outcrop data to build the geological model. The application of this approach to the Central Domain of the Mbere Division led to the production of a synthetic geological map at a scale of 1/75,000. The superposition of this map to the topographic model allows to observe a concordance between the Cretaceous basins represented by their edge faults and the topographic depression zones. The various mineral indicators (primary and secondary) collected during the fieldwork, combined with the geological model (1:75,000 scale) as well as the Cretaceous deposits and vein intrusion models were used to create the mineral indicators and targets map for this sector. All these models can thus be used to underpin mineral exploration projects in the study area. [ABSTRACT FROM AUTHOR]

The reactivation mechanism of multi-slide landslides entails high complexity, and the shear mechanical properties of high groundwater-level landslides are crucial for analyzing the formation mechanism of reactivated landslides. Taking the K39 landslide of Wenma Expressway in Yunnan Province as the research object, we identified the geological and hydrogeological conditions of the landslide, the physical and mechanical properties of the slip zone soil, and the landslide deformation law using geological mapping, geotechnical engineering, indoor testing, and in situ monitoring. The results show the landslide exhibited alternating acceleration and deceleration movements under seasonal heavy rainfall and high groundwater levels. The shear strength of the soil in the deep sliding zone was greater than that of the soil in the shallow sliding zone. The deep and shallow sliding zone soils showed a decrease in shear strength with increased water content. Moreover, the residual strength of the deep sliding zone soil displayed a negative rate with an increased shear rate. In contrast, the residual strength of the shallow sliding zone soil exhibited a positive rate. Furthermore, under different shear rates, the residual internal friction angle and cohesion of the deep sliding zone soil decreased with increased water content, whereas only the residual internal friction angle of the shallow sliding zone soil followed this pattern. Finally, we performed a sensitivity analysis using the GA-BP neural network for the ring shear test parameters of the deep and shallow sliding zone soils, which included consolidation pressure, water content, and shear rate. Our analysis revealed that the residual strength of deep sliding zone soils is most affected by water content, whereas the residual strength of shallow sliding zone soils is most affected by consolidation pressure. Furthermore, it was found that the effect of water content on residual strength is much greater than the effect of shear rate on residual strength for both deep and shallow sliding zone soils. The study results contribute to a unified understanding of how shear rate affects residual strength mechanisms, support research on shear mechanical properties for multiple landslide revivals, and inform engineering practices and policies in landslide-prone areas. [ABSTRACT FROM AUTHOR]

Since the 1970s, it has been widely accepted that the Nördlinger Ries and the Steinheim impact structures represent a crater doublet formed by the simultaneous impact of a binary asteroid in the Middle Miocene. From a biostratigraphic point of view, however, the lowermost crater-lake sediments deposited in the drainless morphological depressions differ in age by ~ 0.5 to 1 Myr. Recent work additionally questioned the double-impact theory due to the occurrence of two vertically separated seismite horizons in North Alpine Foreland Basin deposits, interpreted to result from two different impact-induced seismic events. A continuous double-layer ejecta blanket originally surrounded the Ries crater within a minimum distance of 45 km from its center. Distal Ries ejecta consist of sedimentary and shocked basement rock fragments of the Ries area. The Steinheim crater is located 41 km WSW of the Ries crater and filled by a 'basin breccia' that consist of Middle and Upper Jurassic rock fragments. Most parts of the breccia and overlying crater-lake deposits are preserved. If both craters formed simultaneously, Ries ejecta would have reached the Steinheim area and should be incorporated in the Steinheim breccia or intercalated between the basin breccia and crater-lake deposits. However, no sedimentary or basement rock fragments derived from the Ries crater have ever been found in outcrops or drillings into the Steinheim crater. We conclude the Steinheim impact crater did not exist at the time of the Ries impact and the Steinheim asteroid rather impacted into the outer continuous distal Ries ejecta blanket some 0.5 to 1 Myr after the Ries impact. Geological map of the Ries crater with the present distribution of its ejecta blanket and the geographical position of the Steinheim crater ~41 km WSW of the Ries crater. The Ries ejecta blanket consists of the more proximal type of impact breccia (Bunte Breccia) and the more distal type of impact breccia (Bunte Trümmermassen) [ABSTRACT FROM AUTHOR]

The 2D geological map serves as a synthesis of geological investigations and expert knowledge, making it a crucial data source for bedrock 3D modeling. Nevertheless, insufficient geological information mining has been a problem in previous research utilizing 2D geological maps for bedrock modeling. To address this issue, this paper proposes a 3D bedrock modeling method that incorporates multiple information mining based on 2D geological maps. The method involves extracting surface undulation, occurrence, stratigraphic age, and other information from the 2D geological map multiple times using map-cut cross sections and virtual drills. This information is then stored using the generalized trigonal prismatic (GTP) element. Additionally, the paper introduces connection rules to handle different geological phenomena, such as stratigraphic pinch-out, stratigraphic inversion, stratigraphic duplication, and unconformity contact, and their corresponding GTP types. Finally, the GTPs are connected according to these rules, resulting in the construction of a 3D bedrock model. To validate the method's consistency with expert speculation regarding the expression of geological body structures and occurrence, the paper compares a slice section of the example modeling results with expert hand-drawn section from the same location. The results demonstrate that the proposed modeling method effectively explores the geological information present in the planar geological map and clearly expresses a variety of complex geological formations, enabling the construction of a high-quality 3D bedrock model. [ABSTRACT FROM AUTHOR]

The Basin and Range Province of the western United States has inspired or augmented many important geological ideas but is most famous for the concept of crustal extension. Acceptance of the concept was a slow process. Prior to the recognition of plate tectonics, extension was unexpected and hard to understand; when mapping of the region began in the 1860s, mountain ranges were assumed to be the products of crustal compression due to contraction of the Earth. The first mapping suggested that ranges are anticlinal folds, but the idea of uplift along vertical range-bounding faults arose shortly thereafter. There was recognition starting in the 1880s that at least some faults were normal-sense rather than vertical, which implied extension, but there were decades of dissent by geologists who still promoted the anticlinal-folding idea, thought that inclined faults were reverse faults, or believed that the basins and ranges were created by water or wind or glacial erosion rather than tectonics. Normal faulting gradually became widely accepted, but comprehension of its meaning was hindered by apparent thrust faults in parts of the province that suggested contractional deformation. These faults would later be interpreted as low-angle normal faults, and crustal extension became widely, though not universally, accepted in the 1960s as magnetic anomalies confirmed seafloor spreading. Roughly a century elapsed between the first geologic mapping and general acceptance of crustal extension. A parallel evolution of thought occurred in Africa as a consensus arose that rift valleys were products of extension [ABSTRACT FROM AUTHOR]

Uncertainty of a geoscientific map derived from data sampled by sensory engagement of human experts cannot be quantified from within the processing chain followed to produce the map due to subjective components in the underlying data. Nevertheless, quantified uncertainty associated with such maps would be essentially required for correct information retrieval from such maps. An approach mimicking an expert elicitation through digital agents in an information fusion procedure is suggested to quantify the trustworthiness of a partially subjective map (such as a soil map or any other geoscientific map inherently linked to partial subjectivity, e.g., a geological map). This procedure links a partially subjective map with collocated maps resulting from technical measurements provided with quantified uncertainty. Variation of methodology in this approach results in an ensemble of maps with variable degree of matching with the partially subjective map which allows for probabilistic statements about the trustworthiness of the partially subjective map. This enables including partially subjective maps in further data integration relying on numerical analysis, e.g., in the context of computational modeling or machine learning. By being able to assign a quantitative trustworthiness to a partially subjective map the risk of over-utilization of this map is reduced. [ABSTRACT FROM AUTHOR]

Venus preserves ∼1,000 impact craters, yet to date no impact basins larger than 300 km in diameter—common in the oldest terrains on Mercury, Mars and the Moon—are recognized on Venus. The tessera terrain is Venus' oldest recognized terrain. We describe a ∼1,500 km‐diameter concentric ring‐graben complex preserved on Haasttse‐baad Tessera, Venus that we identify as the Haasttse‐baad Tessera Ring Complex (HTRC). Based on geologic relations and numerical modeling, we propose that the HTRC may represent a Valhalla‐type multiring impact basin formed late during the evolution of its host ribbon‐tessera terrain (rtt). Formation of Valhalla‐type impact basins could involve a unique three‐layer target rheology with a thin elastic layer above a low viscosity layer above a deep strong layer. This multi‐layer rheological sandwich is consistent with crustal rheology previously proposed for the formation of Venus' rtt. If the HTRC is a Valhalla‐type impact basin, it would be Venus' oldest, and currently largest, impact structure, providing a rare window into Venus' ancient past and with implications for early crustal processes on Venus. Plain Language Summary: Venus preserves ∼1,000 impact craters, but no craters larger than 300 km—common on Mercury, Mars, and Moon—are recognized. We describe a large circular structure (∼1,500 km‐diameter) that formed on tessera terrain, Venus' oldest recognized surface type. The structure consists of concentric circular troughs that cut the tessera surface; geologic mapping shows that the structure formed late during tessera formation. We discuss the different mechanisms for forming large circular features marked by concentric rings of structures, and propose that it could be an example of a large impact basin named Valhalla‐type impact basin after a structure present in Jupiter's moon Callisto. Previous research suggests that the formation of these impact basins likely involves a distinctive layering in the impact site consisting of a sandwich of layers with different strengths (strong‐weak‐strong), a configuration previously proposed as necessary to form the host tessera terrain. Numerical models show that forming the circular structure as a Valhalla‐type impact basin is possible if a large meteorite crashes into this three‐layer crust. This unique structure, which might represent a very old and large impact structure, could provide a rare window into Venus' ancient past. Key Points: We describe a unique ∼1,500 km‐diameter concentric ring complex and present detailed geologic maps of the structure and its host tesseraWe propose that this structure may represent a Valhalla‐type impact structure, as supported by geologic mapping and numerical modelingIf the hypothesis is valid, the complex is the largest impact structure recognized on Venus, with implications for early planet processes [ABSTRACT FROM AUTHOR]

Planetary geologic maps are crucial tools for understanding the geological features and processes of solid bodies in the Solar System. Over the past six decades, best practices in planetary geologic mapping have emphasized clear and objective observation, geological interpretation, multi‐sensor fusion, and iterative revision of maps based on new data. We summarize here four ways in which maps serve as indispensable instruments for scientific investigation, from enhancing observations to interrogating surface processes. With respect to space exploration, we underscore the role of planetary geologic maps as tools to link testable, hypothesis‐driven science to exploration goals and provide actionable information for hazard identification, resource evaluation, sample collection, and potential infrastructure development. To further advance the field of planetary geologic mapping, international collaboration is essential. This includes sharing data and maps through FAIR (findable, accessible, interoperable, and reusable) platforms, establishing standardized mapping practices, promoting diverse nomenclature, and fostering continued cooperation in space exploration. Plain Language Summary: We summarize why planetary geologic maps are important for science and space exploration. We review the history of these maps and present four ways in which planetary geologic maps contribute to scientific understanding. We further outline six ways in which maps help humanity plan and execute space missions productively and safely. These endeavors require international participation; thus, we end with a call for collaboration to train the next generation of mappers, develop maps for future missions, and use maps to communicate the significance of space exploration to everyone. Key Points: Planetary geologic maps are critical products that link science goals and objectives to space explorationMaps are also used to support safe and productive surface navigation and are imperative for crewed and robotic surface missionsInternational cooperation is essential to produce maps needed in the coming decade [ABSTRACT FROM AUTHOR]

Large topographic rises on Venus are regions thought to be formed in response to the presence of a mantle plume or mantle upwelling, equivalent to hot spots on Earth. In this work, we study the geology and evolution of one of these large topographic rises, Imdr Regio, based on geologic mapping and analysis of geophysical data of the area. Imdr Regio presents a complex structure with two very different areas: (a) an elevated southeast area that is dominated by volcanism associated with Idunn Mons, a large volcano that has been proposed as a site of recent or even active volcanism; (b) another elevated area in the northwest area that also has a large volcano (Arasy Mons), but that is dominated by volcanism and tectonic activity associated with the formation of the Olapa Chasma rift system. These two very differentiated topographically elevated areas also exhibit differences in their geology, volcanic and tectonic style, and geophysical characteristics, which leads us to suggest that more than the classic volcano‐dominated rise classification attributed to Imdr Regio the area could rather be considered as an intermediate or hybrid volcano‐rift dominated large topographic rise. The evaluation of the different genetic scenarios and its correspondence with the observed geology in the area suggests that the complex geology of Imdr Regio could be better explained if we consider models of hot spot evolution that involve the presence of several mantle plumes or secondary upwellings derived from a mantle plume emplaced at a deeper rheological boundary. Plain Language Summary: Large topographic rises on Venus are the equivalent to hot spots like those responsible for the formation of Hawaii on the Earth. We have studied the geologic evolution of one of these large topographic rises, Imdr Regio, and this research shows that Imdr Regio is complex with two differentiated areas. The southeast is dominated by a large volcano, Idunn Mons, that has been proposed as a site of recent or even active volcanism. In the northwest there is also a large volcano Arasy Mons, but the activity is dominated by the Olapa Chasma rift system. The presence of these two areas with differences in their geology, volcanic and tectonic style, and geophysical characteristics, leads us to suggest that, although this large topographic rise was classified as dominated by the volcano, it could indeed be better classified as an intermediate or hybrid volcano‐rift dominated rise. We also evaluate the different scenarios to explain its formation and conclude that the complex geology of Imdr Regio could be better explained if we consider models of hot spot evolution that involve the presence of several mantle plumes or secondary smaller plumes derived from a mantle plume emplaced at a greater depth. Key Points: We have studied the geology of Imdr Regio, a possible active hotspot on Venus, based on geologic mapping and analysis of geophysical dataImdr Regio presents complex geology dominated by Idunn Mons and Olapa Chasma, classifying it as a hybrid volcano‐rift large topographic riseThe complex geology and the topography of Imdr Regio suggest that it could be the result of multiple or secondary plumes in the area [ABSTRACT FROM AUTHOR]

To mitigate unforeseen incidents, such as key block failure or tunnel collapse during excavation, an appropriate support pattern that correlates with the geological conditions of the rock mass at the tunnel face should be designed. Rock mass evaluations should be conducted through geological face mapping during the construction phase, alongside predictions based on field investigations during the design phase. When marked discrepancies are identified, it is customary to convene an on-site evaluation involving a committee of experts. This study develops a digital tunnel face mapping system that utilises mobile devices to facilitate online evaluations during the construction phase. This system effectively replaces the traditional on-site field evaluation method. Tunnel face mapping can be promptly accomplished using images captured at the excavation face, enabling rapid analysis. In conjunction with the mapping capabilities, the developed system was designed to digitally store geological information, which includes parameters such as rock strength distribution, the spacing and length of discontinuities observed during the mapping process, as well as data pertaining to weathering and the groundwater conditions of those discontinuities. This information was then correlated with the rock mass rating sheet to automate the determination of ratings for each parameter, ultimately leading to a conclusive classification of the rock mass quality. By employing this system for tunnel face mapping and rock quality evaluation, we significantly reduced the discrepancies in the evaluation results that often arise due to the subjective judgement of geologists, as well as human errors that can occur throughout the rating process. [ABSTRACT FROM AUTHOR]

The selection of an optimal dataset is crucial for successful remote sensing analysis. The PRISMA hyperspectral sensor (with 240 spectral bands) and Landsat OLI-2 (boasting high dynamic resolution) offer robust data for various remote sensing applications, anticipating their increased demand in the coming years. However, despite their potential, we have not identified a rigorous evaluation of both datasets in geological applications utilizing Machine Learning Algorithms. Consequently, we conduct a comprehensive analysis using Random Forest, a widely-recommended machine learning algorithm, and employ K-fold cross-validation (with K = 2, 5, 10) with grid-search hyperparameter tuning for enhanced performance. Toward this aim, diverse image-processing approaches, including Principal Component Analysis (PCA), Minimum Noise Fraction (MNF), and Independent Component Analysis (ICA), were applied to enhance feature selection and extraction. Subsequently, to ensure better performance of the RF algorithm, this study utilized well-distributed points instead of polygons to represent each target, thereby mitigating the effects of spatial autocorrelation. Our results reveal dataset-hyperparameter dependencies, with PRISMA mainly influenced by max_depth and Landsat 9 by max_features. Employing grid-search optimally balances dataset characteristics and data splitting (folds), generating accurate lithological maps across all K values. Notably, a significant hyperparameter shift at K = 10 produces the best lithological maps. Fieldwork and petrographic investigations validate the lithological maps, indicating PRISMA’s slight superiority over Landsat OLI-2. Despite this, given the dataset nature and band count difference, we still advocate Landsat 9 as a potent multispectral input for future applications due to its superior radiometric resolution.

Geological mapping is a fundamental tool in the exploration and development of mineral resources. From regional to local scales, it is used in mining projects to identify the mineral resource, to model the deposit, to guide drilling, to plan mineral extraction, in mine design, and in the evaluation of risks and environmental impacts. In other words, it is present throughout the life cycle of the mining project. To understand the relationships that exist between the data obtained from various disciplines associated with geology, such as geophysics, geochemistry, petrography, structural geology, etc., it is appropriate that these be treated as a layers’ system. The importance of the use of this methodology is presented by means of bibliographic research. In particular, the Anaconda system, whose standardized procedures have allowed to obtain good results in the exploration or exploitation of minerals in Yerington-USA, La Costanaza-Spain, Ferrobamba-Peru, Guanajuato-Mexico, Imbabura-Ecuador, Atacama-Chile.

We use the crystallinity of hydrated silica, represented by the 1.4 μm absorption position in orbiter spectroscopic data, as a proxy for the longevity of water–rock interaction in the Syrtis Major region. Geological maps and crater size–frequency distribution analyses are employed to contextualize mineral detections and estimate surface ages. Hydrated silica is detected within two distinct geological units: a younger "volcanic terrain" (vt) unit (∼2.4 Ga) and an older "highland terrain" (ht) unit (3.5–3.7 Ga). Hydrated silica in the vt unit typically has a band position <1.41 μm, consistent with amorphous opal‐A, suggesting these younger terrains have experienced limited interaction with water. In contrast, hydrated silica in the older highlands typically has a band position >1.41 μm, indicating opal‐CT, suggesting that these deposits have had more time to interact with water, while also producing accessory minerals such as kaolinite and Fe/Mg phyllosilicates. Plain Language Summary: This study explores the interactions between water and rocks in a region on Mars known as Syrtis Major by investigating a mineral‐like substance called hydrated silica. The structure of hydrated silica helps us estimate the extent of water interaction and its effects on the rocks. We used satellite data to locate this mineral across Syrtis Major and infer its crystal structure. Furthermore, we developed detailed geological maps and estimated surface ages to understand the geological context. We found that hydrated silica is located in two different types of areas: (a) a younger volcanic region; and (b) an older highland region. In the younger volcanic areas, it appears that less crystalline hydrated silica formed by interaction with small amounts of water, possibly during later volcanic activity. In the older highlands, more crystalline hydrated silica likely interacted with water for a longer duration or in larger amounts. This information aligns with the idea that the older highlands experienced more extensive or long‐lasting interactions with water compared to the younger volcanic regions. It provides insights into different wet periods in Mars' past, aiding our understanding of the planet's geological history and the role water played in shaping its surface. Key Points: We analyzed the crystallinity of hydrated silica in Syrtis Major to infer the extent and longevity of water–rock interactionAmorphous silica is found in young volcanic terrains within Nili and Meroe Paterae and more crystalline silica in the older highlandsOlder highland regions likely underwent a longer interaction with water compared to younger volcanic terrains [ABSTRACT FROM AUTHOR]

There is a growing trend towards utilizing nickel as a raw material for non-steel products due to the increasing demand for nickel up to 2040. Data shows that global nickel production and reserves will increase until 2021. As one of the countries with the largest reserves in the world, this country contributes significantly to global nickel production. This paper will discuss Indonesia's nickel resources, reserves and production related to the distribution of locations, number of resources, number of reserves, grade, sustainability of reserves and their impact on the economy as well as efforts to maintain this sustainability. Previous articles only presented data on Indonesia's nickel reserves and production and an overview of global nickel. The data on nickel resources and reserves come from the 2021 inventory by the Geological Agency, which covers ore resources and reserves and their grades across several classifications. If there is no new data on reserve deposits or planned production rates, it is estimated that the ore reserves with nickel grades ≥ 1.7% will be depleted by 2036, while the ore reserves with Ni grades < 1.7% will be exhausted by 2056. Efforts to increase reserves include increasing exploration activities in brownfield areas, exploring remaining ultrabasic regions, and conducting detailed geological mapping of areas where ultrabasic rock is expected. Apart from raising the issue of the magnitude of nickel potential and mining value, this paper also discusses economic indicators in each nickel producing community using Gross Regional Domestic Product per capita. Based on the results of this analysis, it shows that there are differences in GDP per capita and the value of the mines owned by each region as a nickel producer. [ABSTRACT FROM AUTHOR]

When building 3D models of the subsurface, reconciling several geological and geophysical data of diverse nature, resolutions, coverage, or sensitivity, is challenging, both numerically and petrophysically. In this work, we propose a workflow for mapping selected geological features and characterise their uncertainty using a Bayesian Estimate Fusion algorithm. Different datasets such as 1D probabilistic models derived from geophysical data, drillholes and geological data are combined to produce probabilistic maps of selected geological boundaries, relying on petrophysical and geological assumptions. Leveraging large, high-quality geophysical datasets acquired in the eastern Gawler Craton in South Australia, we demonstrate the applicability of our approach with two examples: (1) we map in 3D the top of a stratigraphic unit in the cover, the Tregolana Shale, using 1D magnetotelluric (MT) and 1D Airborne Electromagnetic (AEM) probabilistic models, drill holes and surface geology; (2) we map the depth to basement using 1D probabilistic MT models, drill holes and interpreted structural information. Our results show that the different resolution, data sampling, depth of investigation and reliability of the utilised datasets can be combined in a complementary fashion, overcoming their respective limitations, to find solutions/models that satisfy all the datasets. We show that probabilistic workflows permit characterisation and reduce uncertainty when mapping the location of features of interest, but also permit the testing of geological hypotheses against other geophysical and geological data. These types of models are valuable to better characterise, interpret, and conceptualise the subsurface, enabling better exploration targeting and supporting efforts to discover new mineral deposits. [ABSTRACT FROM AUTHOR]

The Yerrida Basin in the south-eastern Capricorn Orogen, WA is a Proterozoic sedimentary basin that is prospective for base metals. A regional TEMPEST airborne electromagnetics (AEM) survey over the Capricorn Orogen, coinciding magnetotelluric (MT) survey and available downhole electrical property measurements provide an opportunity to compare the electrical conductivity of the rocks, and the electromagnetic (EM) responses of near surface and deeper sedimentary packages of the Yerrida Basin. Of particular interest is assessing whether it is possible to obtain reliable structural and stratigraphic information from, and to what depth, such as is required for exploration of basin terrains. The MT data were modelled using a 3D inversion algorithm, and the AEM data were modelling using a 1D inversion algorithm. An integrated interpretation of the two datasets allows surface geology to be mapped and for a conductivity section to be created to several kilometres depth. Electrical property measurements showed that one of the stratigraphic units, the Johnson Cairn Formation, is anomalously conductive and hence is readily mapped allowing faults, folds, thickness variations etc to be inferred from the inversions. The underlying and resistive Juderina Formation also gives rise to EM responses, albeit less strong. The results suggest significant modification of the published geological map of the area. The study demonstrates the usefulness of EM methods for exploring sedimentary terrains, but this is greatly facilitated by the presence of conductive stratigraphic units. While not always common practice in green fields exploration, it is recommended that electrical petrophysical measurements are made before committing to large scale EM surveys to better constrain interpretations. [ABSTRACT FROM AUTHOR]

A comprehensive study, including geological mapping, structural and thermochronological analysis, has been carried out on Ivanščica Mountain (NW Croatia), with the aim to reconstruct the tectonic history of the Dinarides, Southern/Eastern Alps and Pannonian Basin transitional zone. Implementation of structural and thermochronological methods enabled a subdivision of Ivanščica Mt. into two structural domains (from bottom to top): Ivanščica Parautochthon and Ivanščica Imbricate Fan and Cenozoic sedimentary cover. In addition, a sequence of deformational events in tectonic history of this transitional zone is proposed, comprising three extensional and four contractional events starting from Middle Triassic until present times. The two oldest deformational events indicate Middle Triassic (D1) and Early Jurassic (D2) extensional pulses and only occur in volcano-sedimentary successions of the Ivanščica Mt. The oldest contractional event (D3) is related to the obduction of a Neotethyan ophiolitic mélange over an Upper Triassic to Lower Cretaceous succession of the eastern margin of the Adriatic microplate, which resulted in thermal overprint of the Ivanščica Imbricate Fan structural domain in Berriasian—Valanginian times (~ 140 Ma). This event was soon followed by a second contractional event (D4), which resulted in thrusting and imbrication of the Adriatic passive margin successions together with previously emplaced ophiolitic mélange, thermal overprint of the footwall successions, fast exhumation and erosion. Apatite fission track data together with syn-tectonic deposits indicate an Hauterivian to Albian age of this D4 event (~ 133–100 Ma). These Mesozoic structures were dextrally rotated in post-Oligocene times and brought from the initially typically Dinaridic SE striking and SW verging structures to the recent SW striking and NW verging structures. The following extensional event (D5) is associated with the formation of SE striking and mostly NE dipping normal listric faults, and ENE striking dextral faults accommodating top-NE extension in the Pannonian Basin. Deformations were coupled with hanging wall sedimentation of Ottnangian to middle Badenian (middle Burdigalian to upper Langhian; ~ 18–14 Ma) syn-rift deposit as observed from the reflection seismic and well data. A short-lasting contraction (D6) was registered in the late Sarmatian (late Serravallian; ~ 12 Ma). The youngest documented deformational event (D7) resulted in reactivation of ENE striking dextral faults, formation of SE striking dextral faults as well as the formation of E to ENE trending folds and reverse faults. This event corresponds to late Pannonian (late Messinian; ~ 6 Ma) to Present NNW-SSE contraction driven by the indentation and counterclockwise rotation of Adriatic microplate. Recognized tectonic events and their timings indicate that Ivanščica was mainly affected by deformational phases related to the Mesozoic evolution of the Neotethys Ocean as well as Cenozoic opening and inversion of the Pannonian Basin. Therefore, the Mesozoic tectono-sedimentary evolution of Ivanščica Mountain proves the paleogeographic affiliation of its non-ophiolitic Mesozoic structural-stratigraphic entities to the Pre-Karst unit of the Dinarides. [ABSTRACT FROM AUTHOR]

Chandarpur–Raipur sequence in Chattisgarh basin is represented as siliciclastic-dominated Chandarpur Group and carbonate-dominated Raipur Group. Here, we introduce 'Devsagar Sandstone Member', the only sandstone-dominated member in the carbonate-dominated Charmuria Formation of Raipur Group, that marks a period of rapid siliciclastic deposition identifying a phase of forced regression between two carbonate platforms of Charmuria–Chandi formations, thereby indicating a drastic change in palaeogeography of Raipur Group. In addition, this study revised the litho-stratigraphy of Mesoproterozoic Chattisgarh basin to clarify the confusion raised due to the existence of different stratigraphy in different basinal parts and different nomenclature for the same lithologic units. Detailed geological mapping with facies analysis in the eastern part of the basin manifests the entire basin-fill succession as part of the Chattisgarh basin itself, rather than sub-dividing some parts as Baradwar sub-basin and Singhora proto-basin. Singhora Group deposited in Singhora proto-basin has already been presented as equivalent of Chandarpur Group. Here we propose, Bamandihi–Saradih–Raigarh formations of Raipur Group in Baradwar sub-basin, as lateral equivalent of Gunderdehi–Chandi–Tarenga formations of Raipur Group and Sarnadih–Nandeli formations of Kharsiya Group in Chattisgarh basin. Inferred depositional environment and tectonic setting of Chattisgarh basin support the lithostratigraphic revision, which will help in basin analysis as well as intrabasinal–interbasinal correlation in regional and global contexts. Research highlights: Devsagar Sandstone Member introduced as the only sandstone-dominated member in carbonate-dominated Charmuria Formation of Raipur Group. Devsagar Sandstone Member represents a tidal shelf in between two carbonate ramp platforms (Charmuria and Chandi), marking a period of rapid siliciclastic deposition and the only phase of forced regression in overall sea-level rising scenario of the carbonate-dominated Raipur Group. Stratigraphy of Chattisgarh basin revised. The entire Chattisgarh succession is represented as deposits of Chattisgarh basin only, without further subdivision into sub-basin and/or proto-basin, thus resolving the stratigraphic and basinal correlation problem. [ABSTRACT FROM AUTHOR]

The selection of an optimal dataset is crucial for successful remote sensing analysis. The PRISMA hyperspectral sensor (with 240 spectral bands) and Landsat OLI-2 (boasting high dynamic resolution) offer robust data for various remote sensing applications, anticipating their increased demand in the coming years. However, despite their potential, we have not identified a rigorous evaluation of both datasets in geological applications utilizing Machine Learning Algorithms. Consequently, we conduct a comprehensive analysis using Random Forest, a widely-recommended machine learning algorithm, and employ K-fold cross-validation (with K = 2, 5, 10) with grid-search hyperparameter tuning for enhanced performance. Toward this aim, diverse image-processing approaches, including Principal Component Analysis (PCA), Minimum Noise Fraction (MNF), and Independent Component Analysis (ICA), were applied to enhance feature selection and extraction. Subsequently, to ensure better performance of the RF algorithm, this study utilized well-distributed points instead of polygons to represent each target, thereby mitigating the effects of spatial autocorrelation. Our results reveal dataset-hyperparameter dependencies, with PRISMA mainly influenced by max_depth and Landsat 9 by max_features. Employing grid-search optimally balances dataset characteristics and data splitting (folds), generating accurate lithological maps across all K values. Notably, a significant hyperparameter shift at K = 10 produces the best lithological maps. Fieldwork and petrographic investigations validate the lithological maps, indicating PRISMA's slight superiority over Landsat OLI-2. Despite this, given the dataset nature and band count difference, we still advocate Landsat 9 as a potent multispectral input for future applications due to its superior radiometric resolution. [ABSTRACT FROM AUTHOR]

This study performed a representative elementary volume (REV) and 3D equivalent continuum study of rock fractures based on fluid simulations of 3D discrete fracture networks (DFNs). A series of 3D DFNs with heterogeneous aperture distributions (the DFN-H model) and uniform apertures (the DFN-I model) were established, in which the fractures were oriented according to the geological field mapping of a high-level radioactive waste candidate site in China. The 3D DFNs of the different model sizes were extracted and rotated in a number of directions to check whether there was a tensor quality of the permeability at a certain scale. The results show that aperture heterogeneity increases the REV size and results in a necessarily larger model size to reach an equivalent continuum behavior, and this effect is more obvious when the fracture density is smaller. The shape of the 2D permeability contour is irregular, with some breaks when the model size is small. As the model size increases, its shape gradually tends to become smooth and approaches an ellipse. The shape of the permeability contours of the DFN-H model is slender compared to the DFN-I model, indicating a larger difference between the minimum and maximum values of the permeability. For the DFN-H model, there is no appropriate approximation for the equivalent permeability tensor over the studied model size range, whereas a good fit of the permeability ellipsoid is obtained for the DFN-I model, and the 3D directional permeability is calculated at this model scale. The corresponding magnitude and direction of the principal permeability are obtained, which can be viewed as the equivalent permeability tensor for the approximated continuum medium. [ABSTRACT FROM AUTHOR]

Gravity measurements have uses in a wide range of fields including geological mapping and mine-shaft inspection. The specific application under consideration sets limits on the survey and the amount of information that can be obtained. For example, in a conventional gravity survey at the Earth's surface a gravimeter is translated on a two-dimensional planar grid taking measurements of the vertical component of gravity. If, however, the survey points cannot be chosen so freely, for example if the gravimeter is constrained to operate in a tunnel where only a one-dimensional line of data could be taken, less information will be obtained. To address this situation, we investigate an alternative approach, in the form of an instrument which rotates around a central point measuring the gravitational potential or its radial derivative on the boundary of a sphere. The ability to record additional components of gravity by rotating the gravimeter will give more information than obtained with a single measurement traditionally taken at each point on a survey, consequently reducing ambiguities in interpretation. We term a device which measures the potential, or its radial derivatives, around the surface of a sphere a gravitational eye. In this article we explore ideas of resolution and propose a thought experiment for comparing the performance of diverse types of gravitational eye. We also discuss radial analytic continuation towards sources of gravity and the resulting resolution enhancement, before finally discussing the possibility of using cold-atom gravimetry and gradiometry to construct a gravitational eye. If realised, the gravitational eye will offer revolutionary capability enabling the maximum information to be obtained about features in all directions around it. [ABSTRACT FROM AUTHOR]

Selecting the most effective prediction model and correctly identifying the main disaster-driving factors in a specific region are the keys to addressing the challenges of geological hazards. Fuyuan County is a typical plateau mountainous town, and slope geological hazards occur frequently. Therefore, it is highly important to study the spatial distribution characteristics of hazards in this area, explore machine learning models that can be highly matched with the geological environment of the study area, and improve the accuracy and reliability of the slope geological hazard risk zoning map (SGHRZM). This paper proposes a hazard mapping research method based on multisource remote sensing data extraction and machine learning. In this study, we visualize the risk level of geological hazards in the study area according to 10 pathogenic factors. Moreover, the accuracy of the disaster point list was verified on the spot. The results show that the coupling model can maximize the respective advantages of the models used and has highest mapping accuracy, and the area under the curve (AUC) is 0.923. The random forest (RF) model was the leader in terms of which single model performed best, with an AUC of 0.909. The grid search algorithm (GSA) is an efficient parameter optimization technique that can be used as a preferred method to improve the accuracy of a model. The list of disaster points extracted from remote sensing images is highly reliable. The high-precision coupling model and the single model have good adaptability in the study area. The research results can provide not only scientific references for local government departments to carry out disaster management work but also technical support for relevant research in surrounding mountainous towns. [ABSTRACT FROM AUTHOR]

The northern inlet channel to Jezero crater (Sava Vallis) terminates in a fan‐shaped depositional feature, part of which blends into the separate well‐known western fan delta that is the field site for the Mars 2020 mission's Perseverance rover. Jezero's northern fan potentially represents either a second fan delta within the crater or a distal portion of the western fan. To constrain the fluvial and sedimentological history of Jezero and place the rover's in situ observations in proper geologic context, we photogeologically map the northern fan deposits at a larger mapping scale than previous studies, using ground‐based imaging from the Perseverance rover for context. Fifteen map units are identified using HiRISE‐based interpretations of geologic characteristics and inferred processes as well as crosscutting relative age relationships. Mapped units are also defined based on orbital data from CRISM and THEMIS to assess their compositional signatures. We interpret the northern fan deposits as older than the uppermost blocky unit in the western fan delta, suggesting that they were deposited contemporaneously with or prior to the deposition of the western fan, and under similar climate conditions. The eastern portion of the northern fan deposits shows evidence of fluvial deposition from Sava Vallis, while part of its western side could represent a distal part of the western fan delta. We synthesize our interpretations to present scenarios for the deposition of the northern and western fans, which can help constrain the history of both watersheds and place it into context within the broader Isidis basin region. Plain Language Summary: The Mars 2020 Perseverance rover has primarily focused on using its scientific instruments to study the delta along Jezero crater's western margin. But there are fan‐shaped features that appear to originate from both the crater's western and northern channels ‐ Neretva Vallis and Sava Vallis, respectively. In this project, we compile orbital images, spectroscopy data sets, and images taken by the rover's Mastcam‐Z instrument to investigate whether the northern fan originated from the northern channel or is an outlying part of the western delta. Based on these observations and the geologic map created using them, we show that the northern fan deposits are older than the uppermost unit mapped in the western delta. We also demonstrate how the western portion of the northern fan deposits could be an outer part of the western delta, while the eastern portion may preserve material from Sava Vallis. We show that some units across the northern and western fans are the same or similar, making this work useful as the rover's mission continues. Finally, we present scenarios that could lead to what we see in Jezero today, helping us to understand the potential history of this area and the relationship between the northern and western watersheds. Key Points: Deposition of Jezero crater's northern fan predates that of its western fan blocky material—the western delta's uppermost surficial unitThe northern fan shows evidence of deposition from Sava Vallis, but part of its western region could be a distal part of the western deltaThe stratigraphic and depositional hypotheses presented provide context for the Mars 2020 mission and help constrain the history of both watersheds [ABSTRACT FROM AUTHOR]

The link between mantle plumes and the formation of large igneous provinces (LIPs) is well established although the anatomy of these remains equivocal. Recent experimental studies and geophysical data suggest that the mantle plume head is more likely to be irregular and asymmetric, rather than an axisymmetric flattened disk. The Emeishan large igneous province (ELIP) provides a unique opportunity to test this hypothesis. According to robust petrographic, geochronologic, and geochemical evidence from the late Permian basalts in the Sichuan Basin, and in conjunction with a comprehensive compilation of geologic maps and published geochemical data from the ELIP, we identified several giant radial "fingering" structures. Based on the shallow mantle source from the center to margin in the ELIP and relief of the lithosphere‐asthenosphere boundary, we propose a new mantle plume model to explain the evolution of the Emeishan plume periphery, where narrow finger‐like protrusions and plumelets developed outwards from the main body of the plume to the edges of the flattened plume head. Dragged fingers might have been torn apart into some plumelets, which dispersed and were trapped beneath the thinnest lithosphere relief, and eventually erupted to form small‐scale flood basalt in the Outer Zone of the ELIP. Key Points: The spatio‐temporal and geochemical characteristics of the Emeishan basalts in the Sichuan Basin are determinedThe Emeishan large igneous province developed fingering structuresA new model, that is, "fingering, torn apart and plumelets," may interpret the evolution of the mantle plume periphery and surface manifestation of the large igneous province [ABSTRACT FROM AUTHOR]

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The information obtained from direct data (geological mapping and boreholes) and indirect techniques (reflection seismology, time-domain electromagnetics and magnetometry) is combined to analyse the northern limit of the Bailén basin (southeastern Spain). This Triassic–Neogene basin is confined by a graben-type structure, limited by two normal faults in the SW–NE direction (the Baños de la Encina-La Carolina fault and Guarromán fault). The movement of these faults was complex, with different pulses occurring over time. Therefore, the subsidence of the basin and the sedimentary filling of the graben were different, giving rise to lateral changes in the facies and thicknesses. This study focuses on the Baños de la Encina fault, chosen as the experimental site to analyse the effectiveness and accuracy of these geophysical techniques to reveal the basement structure and geometry. Seismic reflection allows to detect two faults that caused the subsidence of the eastern sector of the graben. The TDEM method made it possible to calculate the depth of the Palaeozoic basement, as well as reveal the presence of the two aforementioned faults. Magnetic total field data highlight variations in the basement depth that can be used to infer previously unknown fractures, in this case, in the NW–SE direction. [ABSTRACT FROM AUTHOR]

Performing stimulation experiments at approximately 1 km depth in the Bedretto Underground Laboratory for Geosciences and Geoenergies necessitates identifying and characterizing the target fault zone for on-fault monitoring of induced fault slip and seismicity, which presents a challenge when attempting to understand seismogenic processes. We discuss the multidisciplinary approach for selecting the target fault zone for experiments planned within the Fault Activation and Earthquake Ruptures (FEAR) project, for which the aim is to induce the fault slip and seismicity for an earthquake magnitude of up to 1.0 while enhancing the monitoring and control of fluid-injection experiments. Structural geological mapping, remote sensing, exploration drilling and borehole logging, ground-penetration radar, and laboratory investigations were employed to identify and characterize the target fault – a ductile–brittle shear zone several meters wide with an intensely fractured volume spanning over 100 m. Its orientation in the in situ stress field favors reactivation in normal to strike-slip regimes. Laboratory tests showed slight velocity strengthening of the fault gouge. The fault's architecture, typical for crystalline environments, poses challenges for fluid flow, necessitating detailed hydraulic and stress characterization before each of the FEAR experiments. This multidisciplinary approach was crucial for managing rock volume heterogeneity and understanding implications for the dense monitoring network. Successfully identifying the fault sets the stage for seismic activation experiments commencing in spring 2024. [ABSTRACT FROM AUTHOR]

The Mineral King pendant is an ~15-km-long, northwest-striking assemblage of Permian to mid-Cretaceous metavolcanic and metasedimentary rocks that form a steeply dipping wall-rock screen between large mid-Cretaceous plutons of the Sierra Nevada batholith (California, USA). Pendant rocks are generally well layered and characterized by northwest-striking, steeply dipping, layer-parallel cleavage and flattening foliation and steeply northwest-plunging stretching lineation. Northwest-elongate lithologic units with well-developed parallel layering and an absence of prominent faults or shear zones suggests a degree of stratigraphic continuity. However, U-Pb zircon dating of felsic metavolcanic and volcanosedimentary rocks across the pendant indicates a complex pattern of structurally interleaved units with ages ranging from 277 Ma to 101 Ma. We utilize a compilation of 39 existing and new U-Pb zircon ages and four reported fossil localities to construct a revised geologic map of the Mineral King pendant that emphasizes age relationships rather than lithologic or stratigraphic correlations as in previous studies. We find that apparently coherent lithologic units are lensoidal and discontinuous and are cryptically interleaved at meter to kilometer scales. Along-strike facies changes and depositional unconformities combine with kilometer-scale tight folding and structural imbrication to create a complex map pattern with numerous discordant units. Discrete faults or major shear zones are not readily apparent in the pendant, although such structures are necessary to produce the structural complications revealed by our new mapping and U-Pb dating. We interpret the Mineral King pendant to be structurally imbricated by a combination of kilometer-scale tight to isoclinal folding and cryptic faulting, accentuated by, and eventually obscured by, pervasive flattening and vertical stretching that preceded and accompanied emplacement of the bounding mid-Cretaceous plutons. Deformation in the Mineral King pendant represents a significant episode of pure-shear-dominated transpression between ca. 115 Ma and 98 Ma that adds to growing evidence for a major mid-Cretaceous transpressional orogenic event affecting the western U.S. Cordillera. [ABSTRACT FROM AUTHOR]

Since the 2015 Gorkha earthquake in Nepal, the relationship between the geometry of megathrusts and the control it exerts over the nucleation and propagation of major earthquakes has become an important topic of debate. In this study, we integrate new geologic mapping, a newly interpreted cross section from the Daraundi valley of central Nepal, two published cross sections from the neighboring Marsyangdi and Budhi Gandaki valleys, and a suite of 270 thermochronometric ages to create an integrated and validated three-dimensional kinematic model for the central Nepal Himalaya. We use this model to investigate the assertion that the westward propagation of the Gorkha rupture was restricted by deep-seated structures in the Main Himalayan thrust. The integrated kinematic model based on these cross sections indicates that the ~30 km southward step in the Main Central thrust system mapped in the Daraundi valley, along with the corresponding step in the distribution of reset muscovite (Ar-Ar) ages, is not the result of a lateral structure in the modern Main Himalayan thrust. Instead, the step in the surface geology is the result of a considerably shorter Trishuli thrust sheet in the Daraundi transect (~30 km compared to between 105 and 120 km in the other transects). The corresponding southward step in the distribution of reset muscovite Ar-Ar ages is the result of the Lesser Himalayan duplex being completely translated over the Main Himalayan thrust ramp, elevating and exposing rocks heated to >400 °C farther south in the Daraundi transect. Our integrated model also highlights the 10–15 km of out-of-sequence thrusting that occurs on the Main Central thrust system across central Nepal. Importantly, these out-of-sequence thrusts sole directly into the modern Main Himalayan thrust ramp, and, together with the distribution of reset zircon (U-Th)/He and apatite fission track ages, show that the modern ramp is distinctly linear from east to west, with no support for a lateral structure at the ramp or to the south. [ABSTRACT FROM AUTHOR]

The latest geological and geophysical information on the Zeya-Bureya sedimentary basin (Russia, Far East) is summarized. Based on drilling data from corehole and deep wells and 2D and 3D CDPM seismic data, taking into account the integrated interpretation of gravity and magnetic survey data and geological survey materials, a map was compiled for the surface of the pre-Mesozoic basement of the sedimentary basin, as well as structural maps for the top of the Cretaceous formations. The maps reflect a series of rift grabens and uplifts identified by the authors on seismic time sections during their reinterpretation. The method of compiling maps is given. A geological map of sediments overlying the pre-Mesozoic basement of the Zeya-Bureya sedimentary basin and a tectonic map of the sedimentary cover were compiled. During tectonic zoning of the sedimentary cover, the classification of tectonic elements was adopted that is widely used in the tectonic zoning of oil and gas regions, proposed by V.D. Nalivkin and updated at the Trofimuk Institute of Oil and Gas Geology and Geophysics, Siberian Branch, Russian Academy of Sciences (INGG SB RAS). As a result of tectonic zoning in the basin, the Inner Region and the Outer Belt were identified, and the tectonic elements complicating them were characterized. A characteristic feature of the Outer Belt is the presence of large intermediate structures: monoclines and mega- and mesomonoclines. Conversely, the Inner region of the basin is characterized by the presence of a large negative structure, complicated by smaller positive and negative elements. The main stages of the formation and development of the sedimentary cover of the Zeya-Bureya sedimentary basin are identified and described: rifting, early syneclise, late syneclise, and neotectonic. [ABSTRACT FROM AUTHOR]

Mineral exploration works conducted in the Alto Guaporé Gold Province (AGGP), situated in the southwest region of the Amazon Craton in Brazil, faces the challenges of many gold provinces around the world, i.e., declines in the discoveries of new economic deposits and increases in exploration costs. Ground geophysical methods, combined with structural analyses and geological mapping, are valuable tools that have potential to improve accuracy in selecting exploration targets and in determining drilling locations. AGGP deposits are primarily associated with regional N20°–W50° inverse faulting and sheared geologic contacts between Meso-Neoproterozoic siliciclastic metasedimentary rocks and Mesoproterozoic basement (granite and volcano–sedimentary sequences). Mining currently occurring in the central portion of the province drives exploration works towards the many existing targets at the area. Among them, the ABP target is one of the most promising for being located few kilometers north of the Pau-a-Pique mine. At the ABP target, gold is associated with hydrothermal alteration located in the sheared contacts and in the hinge zone of folded metasedimentary sequence. Hydrothermal phases include Fe-oxides, sulfide (py), muscovite and quartz veins. In this study, we use magnetic and geoelectric (induced polarization) surveys coupled with structural and geological mapping to identify potential footprints within the ABP target. The results from induced polarization (IP) profiles successfully mapped the shape and orientation of the main structures down to approximately 350 m at the ABP target, indicating potential locations for hydrothermal alteration hosting gold. Additionally, 3D magnetic data inversions illustrated the distribution of magnetic susceptibilities and magnetization vectors associated with shear zone structures and isolated magnetic bodies. Magnetic data highlighted fault zones along the contacts between metamorphic rocks and granites, while IP data identified areas with high chargeability, correlating with sulfidation zones mineralized with gold. These findings suggest a metallogenic model where gold deposits are transported through deep structures connected to regional faults, implying significant tectonic and structural control over gold deposition. The results underscore the potential of multiparameter geophysics in identifying and characterizing deposits in both deep and strike, thereby advancing our understanding of mineral occurrences in the region and enhancing the search for new mineralized zones. [ABSTRACT FROM AUTHOR]

The main aim of the study is to perform a high-precision mapping of geological features (lineaments and faults) using advanced gravity processing methods. The main techniques used for gravity data processing are the tilt angle of horizontal gradient (TAHG), the improved logistic filter (ILF), the fast sigmoid edge detector filter (FSF), and an edge detection filter based on the arcsine function (ASF). Before applying these edge detection filters to major geological units of North Cameroon, their effectiveness and performance have been assessed on synthetic gravity data and on random noise incorporated synthetic data. In addition, the Euler deconvolution has been used to estimate the position and depth of anomalous gravity sources in the study region. Using these edge detection techniques, a precise mapping of structural lineaments in the region has been established. It appears that the main structural features are trending along the N-S, NNE-SSW and NE-SW directions. The deepest density anomalies in the region are identified in the NW–SE direction, which coincides well with the extension of the Central and West African rift system in the study area. The advanced edge detection techniques and the Euler deconvolution method have both identified a network of superficial lineaments around longitude 13oN and latitude 8oN, and located between 0 and 4 km depth. The NW–SE trending crustal features outlined in the northeast of the region indicate that the area would have been the target of a uniform tectonic activity. This study is crucial to improve the knowledge of the configuration of fractures network, and to a better exploitation of groundwater resources available in the region. [ABSTRACT FROM AUTHOR]

Remote sensing observations represent the primary means in the production of geologic maps of planetary surfaces. However, they do not provide the same level of detail as Earth's geologic maps, which rely also on field observations and laboratory analyses. Color‐derived basemaps can help to bridge this gap by highlighting peculiar surface and compositional properties. Here, we analyzed the spectral properties of the lunar Tsiolkovskiy crater through the definition of spectral units summarizing the information enclosed by a set of selected spectral parameters. We then performed a compositional analysis of the newly derived spectral units that helped us in discriminating the presence and relative abundance of the main mineralogical phases on the Moon. As a final step, we produced a geo‐stratigraphic map of the Tsiolkovskiy crater integrating in a single mapping product both morphologic, stratigraphic and compositional information. The basaltic infilling of the crater is distinguished by three spectral units associated with distinct effusive events presenting a different composition. On the central peak, plagioclase and olivine suggest the presence of Mg‐suite rocks from the lower crust. The continuous ejecta deposits are mostly characterized by impact melts and shocked materials rich in glass or agglutinates related to more mature terrains from which occasionally appear fresher anorthositic and gabbroic outcrops exposed by the inward sliding of the crater walls. Overall, the geo‐stratigraphic map allows inferring compositional variations associated with the different morpho‐stratigraphic units, which clarify and elaborate on the compositional heterogeneities within the lunar crust and the Tsiolkovskiy crater, and its geologic evolutionary history. Plain Language Summary: The main data used to produce geologic maps of planetary surfaces come from orbiting missions. However, geologic maps of Earth provide much more information, relying also on observations made on the field and analyses made in the laboratory. Color images derived from the combination and processing of spectral information can help to make planetary maps more comprehensive, similarly to the Earth's ones, by drawing attention to surface and compositional aspects. In this work, we performed a spectral and compositional study of the Tsiolkovskiy crater on the Moon which enabled us to distinguish the presence and relative quantity of the most common minerals constituting the lunar rocks. We also produced a geo‐stratigraphic map coupling the information about the surface textures and shapes, relative time of deposition, and composition. On the basaltic floor, we discriminated the presence of three different spectral characteristics correlated with a sequence of flooding events showing distinct properties and a central peak exhibiting rocks emerged from the lowest strata of the lunar crust. The continuous ejecta blanket, instead, is characterized by mature materials interspersed by fresher exposures of subsurface materials. To conclude, the new mapping product allows an in‐depth interpretation of the geologic evolution of the Tsiolkovskiy crater. Key Points: Production of a 10‐unit Spectral Units map conveying the spectral and compositional properties within the Tsiolkovskiy craterIntegration of geologic and spectral units to produce a more comprehensive mapping product, namely a geo‐stratigraphic mapElaboration on the geological and compositional evolution of our study area [ABSTRACT FROM AUTHOR]

The Mount Read Volcanics (MRV) of western Tasmania is a belt of Middle to Late Cambrian submarine volcanics and volcaniclastics and one of the major base and precious metal provinces within Australia. Exploration success in the MRV has been in decline in recent years due to a variety of challenges including intensely altered rocks with complex stratigraphy and lithofacies variation, and a lack of accessible outcrop. As a result, local and regional mapping of the MRV is often restricted to Group-level stratigraphy, rendering geological mapping ineffective for identifying decametre-scale mine stratigraphy. Surface rock chip and drill hole samples were collected and analysed using commercially available geochemical assays to create a regional geochemical dataset of the MRV, covering the entire province and all major stratigraphic units. From these data, a lithogeochemical methodology was developed, utilizing Ti/Nb and V/Sc systematics that effectively characterizes the samples according to composition and magmatic processes. This method is shown to be robust to biases due to alteration and lithofacies, eliminating the need for highly selective sampling or extensive data filtering. To demonstrate the utility of this method in an exploration context, data from the K-lens of the Rosebery polymetallic volcanic-hosted massive sulfide (VHMS) deposit was used as a case study. Using Ti/Nb–V/Sc systematics, a rock composition classification was developed that allowed for discrimination of the footwall, hanging wall and host stratigraphy of the Rosebery mine sequence. A geochemical fingerprint for the footwall stratigraphy to mineralization was developed, and by correlating this signature to the regional unclassified samples, geochemical analogues for the Rosebery footwall were readily identified. This approach rapidly reduces the exploration search space and provides valuable information for future mineral exploration. The methodology is applicable in other terrains; however, appropriate orientation studies are required to investigate potential biases due to lithofacies, alteration and mineralogical variability. [ABSTRACT FROM AUTHOR]

The geological structure of the evaporite formation in the Amu Darya syneclise is a complex system that provides valuable insights into the region's geological history and economic potential. The study aims to analyse the main characteristics of the geological structure of the evaporite formation in the Amu Darya syneclise to expand knowledge of the geological and environmental history of the region and to identify the potential of these deposits for various applications. The methods used for this study included geological mapping, mineralogical analysis, stratigraphic analysis and geochemical research. The study identifies three distinct water-bearing horizons within the evaporite complex: Sharaplinsky, Yolotan, and Sakar. These horizons exhibit varying characteristics in terms of composition, water content, and distribution across the basin. Geomorphological manifestations, such as salt lakes and salt marshes, play a crucial role in understanding the ecological and geological history of the region. The evaporite formation holds substantial economic importance, hosting valuable resources including salts, oil, and gas. This geological structure supports regional industrial development, job creation, and overall economic growth. The study also highlights the need for further research into the geology and geomorphology of the Amu Darya syneclise to better understand the formation and dynamics of evaporite deposits and their role in the region's current environmental and economic sectors. The study emphasizes the need for efficient technologies and methods for resource extraction and management to ensure sustainable development and minimize environmental impact. The research provides crucial data for optimizing mineral extraction strategies and developing effective natural resource management approaches. It underscores the importance of understanding the geological structure for sustainable ecological and economic development in the region. The practical significance of this study is a basis for developing more effective natural resource management strategies based on an understanding of the geological processes of evaporite sedimentation in the Amu Darya syneclise, which is key to the sustainable development of the region's ecological and economic systems. [ABSTRACT FROM AUTHOR]

Machine learning and remote sensing techniques are widely accepted as valuable, cost-effective tools in lithological discrimination and mineralogical investigations. The current study represents an attempt to use machine learning classification along with several remote sensing techniques being applied to Landsat-8/9 satellite data to discriminate the various outcropping lithological rock units at the Duwi Shear Belt (DSB) area in the Central Eastern Desert of Egypt. Multi-class machine learning classification, multiple conventional remote sensing mapping techniques, spectral separability analysis based on the Jeffries-Matusita (J-M) distance measure, fieldwork, and petrographic investigations were integrated to enhance the lithological discrimination of the exposed rock units at DSB area. The well-recognized machine learning classifier (Support Vector Machine—SVM) was adopted in this study, with training data determined carefully based on enhancing the lithological discrimination attained from various remote sensing techniques of False Color Composites (FCC), Principal Component Analysis (PCA), and Minimum Noise Fraction (MNF), along with the fieldwork data and the previously published geologic maps. High overall accuracy of the SVM classification was obtained, however, inspection of the individual rock unit classes' accuracies revealed lower accuracy for certain types of rock units which were also found associated with lower separability scores as well. Among the least separable rock units were; metagabbro rocks that showed high spectral similarity with the volcaniclastic metasediments rocks, and the metaultramafics of the ophiolitic mélange showed spectral attitude of high correlation to that of the Hammamat volcanosedimentary rocks. Target-oriented Color Ratio Composites (CRC) technique was implemented to better discriminate these hardly separable rock units. A final integrated geological map was obtained comprising the various discriminated Neoproterozoic basement rock units of the DSB area. The successfully mapped litho-units include; Meatiq Group (amphibolites, gneissic granitoids, and mylonitized granitoids), ophiolitic mélange (metaultramafics, metagabbro-amphibolites, and volcaniclastic metasediments), Dokhan volcanics, Hammamat sediments, and granites. An adequate description of these rock units was also given in light of the conducted intense fieldwork and petrographic investigations. [ABSTRACT FROM AUTHOR]

Geological mapping involves the identification of elements such as rocks, soils, and surface water, which are fundamental tasks in Geological Environment Remote Sensing (GERS) interpretation. High-precision intelligent interpretation technology can not only reduce labor requirements and significantly improve the efficiency of geological mapping but also assist geological disaster prevention assessment and resource exploration. However, the high interclass similarity, high intraclass variability, gradational boundaries, and complex distributional characteristics of GERS elements coupled with the difficulty of manual labeling and the interference of imaging noise, all limit the accuracy of DL-based methods in wide-area GERS interpretation. We propose a Transformer-based multi-stage and multi-scale fusion network, RSWFormer (Rock–Soil–Water Network with Transformer), for geological mapping of spatially large areas. RSWFormer first uses a Multi-stage Geosemantic Hierarchical Sampling (MGHS) module to extract geological information and high-dimensional features at different scales from local to global, and then uses a Multi-scale Geological Context Enhancement (MGCE) module to fuse geological semantic information at different scales to enhance the understanding of contextual semantics. The cascade of the two modules is designed to enhance the interpretation and performance of GERS elements in geologically complex areas. The high mountainous and hilly areas located in western China were selected as the research area. A multi-source geological remote sensing dataset containing diverse GERS feature categories and complex lithological characteristics, Multi-GL9, is constructed to fill the significant gaps in the datasets required for extensive GERS. Using overall accuracy as the evaluation index, RSWFormer achieves 92.15% and 80.23% on the Gaofen-2 and Landsat-8 datasets, respectively, surpassing existing methods. Experiments show that RSWFormer has excellent performance and wide applicability in geological mapping tasks. [ABSTRACT FROM AUTHOR]

Areas with potential to host clay deposits in Las Tunas province were identified by combining remote sensing data and geological information integrated in the Geographic Information System (GIS). Geological mapping, remote sensing and geospatial modeling techniques were used. The findings reveal a heterogeneous distribution of areas with moderate, high and very high potential to host clay deposits throughout the region, with significant concentrations in Manatí, Tunas, Jobabo, Colombia and Amancio municipalities. The integration of remotely sensed data and geological sources in a GIS environment are effective and feasible for this type of analysis. [ABSTRACT FROM AUTHOR]

During the sampling of a stratigraphic section along the shore of the Fiastra Lake (Carg Project - Sheet 313 “Camerino” of the Geological Map of Italy at 1:50 000 scale), a small rock boulder with partially exposed bony material was discovered at the base of a small cliff at the northern termination of the Sibillini Mts. In this area, the classical facies of Umbria-Marche stratigraphic succession are well-exposed. The Oligocene-Miocene portion of the succession is represented by the ~200 m-thick Scaglia Cinerea Formation, passing upwards to the ~100 m-thick Bisciaro Formation. The microfossil assemblage has allowed the specimen to be constrained to the lower Burdigalian. The skeletal remains were examined using a CT-SCAN, a non-invasive method that has proven to be highly performing. The analysis revealed some articulated vertebrae, deformed by lithostatic compaction, which are attributed to a shark of the order Lamniformes. Subsequently, the vertebrae were digitally isolated, extracted from the surrounding matrix, and rendered into three-dimensional prints. Through digital retro-deformation, the body length of the lamniform shark was estimated to be approximately 4 metres. Further considerations on the vertebrae allowed us to infer that the studied shark had similarities to either Isurus oxyrinchus Rafinesque, 1810 or Carcharodon carcharias Linnaeus, 1758. The development of a dead-fall microbial community likely facilitated the preservation of the vertebrae. The studied specimen represents the first occurrence of a lamniform shark in the Lower Miocene of the Umbria-Marche Domain and represents one of the very rare recorded occurrences of lamniforms from the Lower Miocene of Italy [ABSTRACT FROM AUTHOR]

Apart from within the Arumbera Sandstone that spans the Ediacaran–Cambrian boundary, the entire Neoproterozoic succession of the Amadeus Basin has been generally believed to be devoid of metazoan fossils, despite features of possible biogenic origin having been described in the earliest geological mapping reports. Herein are described a suite of curious, rounded impressions preserved upon the surface of a sandstone bed from the basal Neoproterozoic unit, the quartzitic Heavitree Formation that dates to ca 850 Ma. Compared with rounded structures of both organic and inorganic origin, these features resemble fossils of stranded medusae, both modern and ancient, and thereby add a potentially pelagic lifeform to previously described burrowing and sessile forms of likely metazoans, which are preserved as fossils/trace fossils within the Tonian period of the Neoproterozoic elsewhere in the basin. An organic origin for these features would support the contention that the Amadeus Basin harbours the earliest evidence that macroscopic life flourished, albeit briefly, some 215 million years prior to the start of the Ediacaran period and 250 million years before metazoans successfully colonised the late Ediacaran seas. Curious rounded impressions upon a scree sample of Heavitree Formation (ca 850 Ma) are best compared with fossils of stranded jellyfish, both modern and ancient. Such impressions add to the phyla seemingly extant within the Amadeus Basin during the Tonian Period (early Neoproterozoic). Such phyla suggest that metazoan life evolved some 250 Ma earlier than generally believed, although became extinct locally some 10 Ma later. Extinction occurred at ca 840 Ma when changing climate caused the enclosed Amadeus Basin to evolve from conducive shallow aquatic conditions to a harsh evaporitic salt pan. Two later forays into metazoan evolution within the basin are evidenced by burrow-like tubular structures at ca 720 Ma and the Arumberia fossils at ca 560 Ma. [ABSTRACT FROM AUTHOR]

The Elat/Timna area in Southern Israel provides an unparalleled opportunity for geological field studies due to its unique geology, spanning from the Neoproterozoic to the Holocene. The well-exposed rocks document the variability and evolution of three major processes: the creation of the Arabian-Nubian Shield during the Neoproterozoic, the accumulation of the Cambrian to Eocene sedimentary sequence, and the Miocene to Recent evolution of the Dead Sea Transform, an active plate boundary. The area's geological diversity and extensive documentation of its geology have made it a particularly important study site for geoscience students. Recently the Geological Survey of Israel published new 1:50,000 scale geological maps of the area, updated by additional fieldwork and presented in a series of reports. This paper presents a brief geological overview and a description of six key locations, complete with maps and photos that are a showcase document to the area's geological uniqueness as an excellently-exposed window into 800 million years of Neoproterozoic to Holocene evolution at the NE African plate. [ABSTRACT FROM AUTHOR]

The evolution of map development has been shaped by advancing techniques and technologies. Nevertheless, field and remote mapping with cabinet data analysis remains essential in this process. Geological maps are thematic maps that delineate diverse geological features. These maps undergo updates reflecting changes in the mapped area, technological advancements, and the availability of new data. Herein, a geological assessment example focused on enhancing mapped data using digitally processed historical (legacy) aerial images is presented for a case study in the Dinarides karst area in Croatia. The study area of Bribirske Mostine is covered by the Basic Geological Map of Yugoslavia (BGMY) at a 100,000 scale, which was developed during the 1960s. As the BGMY was developed 60+ years ago, one of its segments is further analyzed and discussed, namely, faults. Moreover, applying modern-day technologies and reinterpretation, its data, scale, presentation, and possible areas of improvement are presented. Georeferenced digital historical geological data (legacy), comprising BGMY, archive field maps, and aerial images from 1959 used in BGMY development, are reviewed. Original faults were digitalized and reinterpreted within the geographic information system with the following conclusions: (i) more accurate data (spatial positioning) on faults can be gained by digitally processing aerial photographs taken 60+ years ago with detailed review and analysis; (ii) simultaneously, new data were acquired (additional fault lines were interpreted); (iii) the map scale can be up-scaled to 1:25,000 for the investigated area of Bribirske Mostine; and (iv) a newly developed map for the Bribirske Mostine study area is presented. [ABSTRACT FROM AUTHOR]

Meteoroid impacts produce different types of fractures and damage zones beneath impact craters. The 3D geometry of these features reflects the trajectory and energetics of an impact event. In this study, we mapped the impact damage zone beneath the 1.88‐km‐diameter Lonar crater, emplaced in Deccan basalts, using Ambient Noise Tomography (ANT). A network of 23 broadband seismic stations in and around the crater yielded a 1.2 km deep 3D shear wave velocity (VS) image covering ∼7 km by ∼5 km area. It revealed ∼500–900‐m‐thick heterogeneous target basalt flows, underlain by an undulating Archean granite‐gneiss basement. A substantial reduction in VS is observed beneath the crater. The original crater floor was found at a depth of 400 m below the crater rim, which is filled by impact breccia and lake sediments. Beneath the original floor, we found an oval‐shaped, asymmetric 200‐m‐thick lensoidal low‐velocity layer with a tongue‐like feature beneath the southwestern ejecta blanket. The damage zone is inferred to have formed as a result of oblique impact, in which the projectile arrived from northeast to southwest direction. The VS reduction in the low‐velocity layer was used to calculate the amount of impact damage in it. The oblique impact produced a more elevated southwestern crater rim. Impact‐related near‐surface fracture zones up to a radial distance of >1 km beneath the ejecta blanket were also found. We suggest that impact damage beneath impact craters on Earth and other planetary bodies may be imaged using ANT. Plain Language Summary: Impact craters are ubiquitous on planetary surfaces. The impact produces both surface and sub‐surface changes, including fracturing and damage beneath the crater floor. The 3D geometry of the damage zone depends on the impact angle and velocity. While vertical impacts generate symmetric damage zones beneath the craters, oblique impacts produce asymmetrical damage zones with greater damage in the downrange direction. Field geological mapping provides limited information about these features, while the Ambient Noise Tomography (ANT) brings out a complete shape and size of the damage zone in the sub‐surface. The shear wave velocity image also provides the characteristics of target rocks within and outside the impact crater. In this work, we carried out the ANT study of Lonar crater, emplaced in Deccan basalts in India, using a network of 23 broadband seismometers. This study revealed a ∼500–900‐m‐thick heterogeneous basaltic target underlain by an Archean granite‐gneiss basement, and an asymmetric damage zone beneath ∼400‐m‐deep original crater floor because of southwest directed oblique impact. We quantified the amount of impact damage beneath the original crater floor. The ANT can be used for imaging damage zones beneath impact craters on Earth and other solid planetary bodies, thus providing more insight into impactor trajectories. Key Points: Ambient noise tomography reveals a 500–900 m thick heterogeneous basaltic target underlain by Archean granite basement beneath Lonar craterAn asymmetric damage zone is found beneath the 400 m deep original crater floor filled by impact breccia and lake sedimentsAsymmetric topography and impact damage zone geometry are consistent with a southwest‐ward oblique impact trajectory [ABSTRACT FROM AUTHOR]