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We present new interpretations and mapping that define the distribution, extent, and sediment thickness of 25 primarily offshore sedimentary basins within New Zealand's Exclusive Economic Zone (EEZ) and Extended Continental Shelf (ECS). These basins cover ∼1.64 million km2 of the ∼5.8 million km2 (∼28%) of New Zealand's offshore territory. The sedimentary basins formed in different tectonic settings. Most initially formed during the mid- to Late Cretaceous in either a rift-related setting during Gondwana break-up, or within or atop the paleo Gondwana subduction margin. Others formed due to the onset of mid-Paleogene sea-floor spreading, or are related to Neogene–Quaternary subsidence driven by subduction processes. Slight to significant late Paleogene to Quaternary tectonic overprints are pervasive in basins located within the Hikurangi subduction margin's deformation zone. Knowledge of the distribution and extent of these basins was refined during the multi-year 'Atlas of Petroleum Prospectivity' research programme, which builds upon many decades of previous research. New digital structure, isochore, and paleogeographic maps, along with annotated seismic reflection profiles, have been developed where data coverage has allowed, using a consistent set of age-equivalent seismic horizons tied to the New Zealand Geological Timescale. Maximum total sediment thickness of ∼11 km occurs in Taranaki Basin. [ABSTRACT FROM AUTHOR]

Systematic fish fossil studies are scarce in the tropical West Pacific, which hinders our understanding of historical processes that resulted in the modern fish fauna in the region. To fill this gap, we reviewed published and domestic fish fossil reports in the Philippines, assessed the status of paleoichthyological research, described fish fossil-bearing sedimentary basins and formations, highlighted difficulties, and provided prospects for future research opportunities. So far, six published documents have reported Oligocene to Pleistocene fish fossils from three sedimentary basins: Cagayan Valley Basin, Ilocos-Central Luzon Basin, and Visayan Sea Basin. Based on domestic reports, we have identified six additional stratigraphic units containing Miocene to Pleistocene fish fossils, such as skeletons, mouth plates, teeth, vertebrae, and otoliths. Moreover, we identified 58 fossiliferous units from eight sedimentary basins for future explorations. The lack of expertise, however, hinders the systematic sampling and study of fish fossils in the country. We recommend developing a national program for paleoichthyological research and promoting paleontology by engaging researchers, government agencies, private collectors, and the general public. This concerted effort will enhance our understanding of the paleoichthyological fauna of the Philippines, which is vital in bridging the knowledge gap on fish fossil records in the West Pacific region. [ABSTRACT FROM AUTHOR]

As a potential renewable and clean energy source, the distribution and exploration prospects of natural hydrogen have garnered widespread attention. However, the limitations in understanding the formation mechanisms and accumulation patterns of underground natural hydrogen have significantly constrained its efficient exploration and utilization. This study reports H2 content and isotopes in natural gas from deep formations in sedimentary basins through geochemical analysis of 58 conventional gas samples from the Sinian to Triassic strata in the central Sichuan Basin. We discovered that H2 content in deep natural gas in central Sichuan generally exceeds 0.1%, with a maximum of 1.6%, and hydrogen isotopes ( δ 2 H H 2 ) range from −850‰ to −586‰. Analysis of the geological conditions, hydrogen generation mechanisms, and isotope fractionation characteristics in the study area confirms that microbial fermentation or in-situ organic matter cracking are not effective pathways for deep H2 generation. Combined with helium content and isotope analysis of the natural gas, it is inferred that the volcanic basement in the central Sichuan area is the potential source rock for natural H2 in the Sinian to Triassic strata. Specifically, H2 originates from the radiolysis of water and hydrothermal reactions of Fe(II) in the basement granite. Additionally, a diffusion fractionation model reveals significant isotope fractionation during the migration and accumulation of deep H2 into sedimentary reservoirs, which lead to anomalously light δ 2 H H 2 in deep natural gas in central Sichuan. This indicates that the underground natural hydrogen accumulation is in a long-term dynamic process, with simultaneous H2 accumulation and dissipation in the gas reservoirs. This research not only elucidates the formation mechanism of deep H2 but also provides insights for the resource potential of natural hydrogen in sedimentary basins. [ABSTRACT FROM AUTHOR]

The NW Yangtze Block has long been regarded as a passive continental margin during Ediacaran and Cambrian. However, with the deepening of the regional geological survey and deep oil and gas exploration, the depositional sequence and palaeogeographic patterns of Ediacaran and Cambrian in the Sichuan basin are not consistent with the general sedimentary evolution process of passive margin more and more. To fully understand the tectonic property and palaeogeography of the NW Yangtze Block, a comprehensive study of the whole rock geochemistry, zircon U-Pb chronology and Hf isotopic composition analysis were carried out on the Weimen volcanic rocks, which mainly consist of trachyte, trachy-andesite, andesite, dacite, and rhyodacite in Maoxian area. They have high light rare earth element (LREE) and large ion lithophile element (LILE) concentrations, but are depleted in high field strength elements (HFSE). They are characterized by having high K2O+Na2O (5.60–9.48%), MgO (1.47–4.58%), Ce/Yb (11.67–25.79), and normalized hypersthene (Hy = 2.14–14.17), indicate an unambiguous feature of the shoshonite series. LA-ICP-MS zircon U-Pb dating results show that the volcanic rocks have crystallization ages ranging from 528 Ma to 523 Ma, with positive zircon εHf (t) ranging from + 1.31 to + 5.26. In combination with previous studies, the early Cambrian shoshonite series in Maoxian area are interpreted to be formed in a continental collision setting. Therefore, the discovery of the shoshonite series suggests that the NW Yangtze Block has experienced an important process of continental subduction and collisional orogeny in response to the Gondwana assembly, and consequently provided a large amount of terrigenous sources to rapidly fill into the early Cambrian foreland basin. Highlights: Firstly report 530-520 Ma shoshonite series in NW Yangtze. Weimen shoshonite series demystify the dynamics of the cratonic rift. NW Yangtze underwent continental collision and rapid uplift from Ediacaran to Cambrian. [ABSTRACT FROM AUTHOR]

In ground-motion modeling, the estimated level of ground shaking at any given location for an expected earthquake scenario depends on the contributions from the source component (type of fault mechanism and size of the fault slip), the path component (distance between the source and site of interest, and the geologic characteristics of that region), and the site component (the local geology at the site of interest). Each component captures some level of variability and uncertainty in the overall ground-motion estimate. In particular, the site component represents the potential amplification (or de-amplification) of the seismic waves that may lead to magnified and prolonged ground shaking at any given location. This feature is referred to as site effects and in current ground-motion models (GMMs) is dependent on the time-averaged shear wave velocity in the upper 30 m of the earth's crust (Vs30) and the depth to a particular shear wave velocity iso-surface ("basin depth," zx). The latter is responsible for determining the contributions of basin effects, which is additional ground-motion amplification due to three-dimensional effects such as trapped seismic waves that lead to surface wave generation. However, an evaluation of the relationship between zx and basin locations reveals cases of misclassification that is a result of geologic variability (i.e. zx is not sufficient in differentiating basins from non-basins). The study performed in this article proposes a resolution in the form of a statistical classification model that determines the probability of a location residing within or outside a basin based on simple geologic features such as ground surface texture. [ABSTRACT FROM AUTHOR]

The origins of natural hydrogen in natural gas systems of sedimentary basins and the capacity of these systems to store hydrogen remain inadequately understood, posing crucial questions for the large-scale exploration of natural hydrogen. This study reports on the natural gas composition, stable carbon and hydrogen isotopic values, and helium isotopic values of gas samples collected from the Qingshen gas deposit within volcanic rocks of the Songliao Basin. Natural hydrogen primarily originates from water radiolysis, water-rock interactions (WRI), and mantle. The Qingshen gas deposit contains 95.23 × 109 cubic meters of abiotic CH4, of which 15.24 × 109 cubic meters was generated through hydrogen conversion via Fischer-Tropsch synthesis, with the maximum original hydrogen reserves calculated to be approximately 61.9 × 109 cubic meters. We estimated that the study area has generated a maximum total of 572 × 109 cubic meters of radiolytic hydrogen, 248 × 109 cubic meters of WRI hydrogen, and 127 × 109 cubic meters of mantle-derived hydrogen. [ABSTRACT FROM AUTHOR]

Massive injection of 13C depleted carbon to the ocean and atmosphere coincided with major environmental upheaval multiple times in the geological record. For several events, the source of carbon has been attributed to explosive venting of gas produced when magmatic sills intruded organic-rich sediment. The concept mostly derives from studies of a few ancient sedimentary basins with numerous hydrothermal vent complexes (HTVCs) where craters appear to have formed across large areas of the seafloor at the same time, but good examples remain rare in strata younger than the Early Eocene. We present geophysical data documenting at least 150 large (km-scale) craters on the modern seafloor across ∼148,000 km2 of Scan Basin in the southern Scotia Sea, a remote region offshore Antarctica. Seismic and bathymetric information reveals the craters relate to vertical fluid pipes extending above dome-shaped forced folds and saucer-shaped igneous sills. Presumably, magmatic intrusions deform overlying sediment and produce thermogenic gas, where buoyant hydrothermal fluids migrate upwards from sill flanks through V-shaped gas chimneys to the seafloor. Fluid expulsion, driven by excess pore pressure, enhances vertical conduits and creates collapse structures on the seafloor. Age estimates for sill emplacement and crater formation come from correlations of seismic reflectors with bore hole data collected on IODP Expedition 382. Sills intruded into sediment at least two times, first about 12–13 Ma (Middle Miocene), which occurred with deep intrusions of stacked composite sills, and once about 0.9 Ma and associated with volcanism along Discovery Bank, which may have reactivated previous fluid venting. Crater reactivation has occurred since 0.9 Ma, although probably episodically. Importantly, at present-day, numerous craters related to sills and fluid pipes populate the seafloor above a young sedimentary basin, and the ocean and atmosphere are receiving massive quantities of 13C depleted carbon. The two phenomena are unrelated but, with changes in global climate and sedimentation, the craters could be filled simultaneously and give an impression in the rock record of rapid and coeval formation coincident with carbon emission. Interpretations of ancient HTVCs and their significance to global carbon cycling needs revision with consideration of modern seafloor regions with HTVCs, notably Scan Basin. [ABSTRACT FROM AUTHOR]

Complex geological, gas geochemical and hydro meteorological studies were conducted to investigate the methane fields present in the bottom sediments and seawater of the Red River and Phu Khanh sedimentary basins. We demonstrate that the system of tectonic faults that formed the sedimentary basins of the Red River and the Phu Khanh (the eastern shelf and slope of Vietnam) created the necessary conditions for the generation and migration of endogenous methane into the bottom sediments and seawater. It is shown that dissolved methane in seawater can be transported by marine currents, which in turn can be influenced by seasonal and irregular synoptic processes. The research shows that part of the dissolved methane contained in the waters above the Ken Bau gas field can be transported to the south by the coastal Vietnamese current, which adapts to the conditions of the winter northeast monsoon. It is concluded that there could be at least two deep sources of hydrocarbon gas emissions in the Phu Khanh basin. The impact of Typhoon Nakri on the transport of dissolved methane in the water column of the Phu Khanh sedimentary basin has been investigated. The typhoon could create favorable hydrodynamic conditions for the movement of dissolved gases from oil and gas deposits near the coasts of the islands of Kalimantan and Palawan to the Phu Khanh basin. A possible route for this transfer has been identified. [ABSTRACT FROM AUTHOR]

In Colombia, natural hydrogen (H2) was recently declared a source of unconventional renewable energy. An opportunity has been recognized to take advantage of information on the infrastructure of oil fields as a springboard for H2 exploration in the country's sedimentary basins. Establishing similarities and identifying components of the possible H2 systems in the different geological contexts where the presence of H2 has been proven in Colombia's sedimentary basins allows the establishment of the probability of H2 in the Ecopetrol oil and gas fields in Colombia. The components of H2 systems include potential H2 source rocks and reservoirs. Potential accumulations need to be confirmed through measurements, sampling, and well testing. The main types of H2 well exploration carried out in this study resemble those in oil fields and include surface surveys, logging while drilling (mud gas and petrophysics), and downhole sampling. In the case of a hydrocarbon field in the Llanos Basin, a detailed seismic and geological review, supported by surface survey indications of H2 traces, prompted further investigation while drilling wells in the basin to establish the provenance and distribution of H2. Based on the proposed workflows, we evaluated possible strategies in the area. Given the positive evaluation of the possible elements of a theoretical H2 strategy, a sampling plan was defined both in the well and on the surface that will reduce the uncertainty of the prospect of natural H2 in the studied basin but may also be applied to similar geological settings worldwide. This study shows the application of such an H2 exploration strategy, leading to the presented results from the first well and confirming the presence of an active natural H2 system in the Llanos Basin. [ABSTRACT FROM AUTHOR]

I f rifting in the North American Midcontinent reflects early Flood processes, then defining the thickness and distribution of the total diluvial record requires mapping the base of these rifts. Using publicly available data, we created a 3D map of the base of the largest, the Midcontinent Rift. Combined with similar maps of the East Continent Basin, the Reelfoot Rift-Rough Creek Graben, and Rome Trough, we propose a basal diluvial boundary for the upper Midcontinent Region. The scale of the rifting is seen in the volume of fill; rift fill comprises well more than half of the total diluvial volume. Despite significant erosion, the rifts remain as stunning reminders of crustal disruption at the onset of the Flood, revealing significant geological activity-structural, erosional, volcanic, intrusive, and depositional-before the transgressive marine front of the Flood. Using these maps, quantitative estimates of all of the Flood and Ice Age rock records can be estimated, providing a solid basis for forensic interpretation. [ABSTRACT FROM AUTHOR]

The tectonic evolution of the Palaeocene–Eocene Tethys Himalayan foreland basin plays a crucial role in reshaping the collisional orogenic process of the Yarlung–Tsangpo oceanic basin. However, studies examining the sedimentary response during the tectonic evolution of the foreland basin are lacking. In this study, through a detailed field investigation and analysis of Palaeocene–Eocene strata in the Tingri area, we clarified the evolution of the Tethys Himalayan tectonic regions and its sedimentary response. Carbon and oxygen isotopes, geochemistry and detrital zircon U–Pb dating demonstrated that the lower Palaeocene Jidula Formation and upper Palaeocene–lower Eocene Zongpu Formation were deposited in a coastal–shallow marine environment, with the detritus sourced from the northern Indian passive margin. The upper Eocene Pengqu Formation was deposited in a deltaic environment, with its detritus sourced from the Gangdese arc and the Yarlung–Tsangpo suture zone at the active continental margin. Combined with the nearshore subaqueous fan branch channel of the Jidula Formation and the slump deformation of the Zongpu Formation, the Palaeocene–Early Eocene southern Tethys Himalaya in the Tingri area was located in the forebulge of the peripheral foreland basin. The marine–continental interactive delta of the Pengqu Formation and its provenance from the Gangdese magmatic arc indicate that the Tingri area was situated in the foredeep of the peripheral foreland basin during the Late Eocene. The study provides valuable insights into the collisional orogenic processes between the Indian and Eurasian plates. [ABSTRACT FROM AUTHOR]

Carbonate cementation in the Upper Permian sandstones informs the timing and temperature of hydrothermal activity in the south‐western Ordos Basin. This study presents a detailed examination of these hydrothermally influenced carbonate cements, constraining their age, carbonate diagenesis and relationship with regional geodynamic evolution. Sedimentological analyses demonstrate the development of deltaic plain and front sand bodies in the study area, which resulted in interbeds of volcanic matrix‐rich sandstones with matrix‐free sandstones. Petrography and electron microprobe analysis reveal four carbonate mineral growth phases of matrix‐free sandstones in the following sequence; scarce pure siderite, scarce Mg‐rich siderite, abundant blocky calcite and moderately abundant grain‐replacing calcite. The fluid inclusion data show anomalies of homogenization temperature of blocky carbonate cements during early diagenesis, over a wide range of ca 148 to 228°C. In addition, blocky carbonate cements show low δ13C (−5.9 to −13.1‰ Vienna PeeDee Belemnite) and δ18O (clustered tightly from −12.4 to −14.6‰ Vienna PeeDee Belemnite) values, interpreted to result from elevated temperatures during cementation, associated with activation of basement faults and concomitant hydrothermal fluid intrusion triggered by oceanic crust subduction in the south‐west margin of the Ordos Basin. Using in situ calcite U–Pb geochronology, the timing of hydrothermal activity was constrained to ca 247.0 ± 11 to 248.2 ± 4.7 Ma. This work provides a case study for applying intergranular calcite U–Pb dating to determine the absolute timing of fluid flow in sedimentary basins, offering tremendous potential to capture snapshots of various diagenetic evolution stages in sediments. The proposed diagenetic model can also provide new insights and understanding regarding hydrothermally influenced sediments. More importantly, hydrothermal activity may have commenced earlier than previously thought. The North Qinling Orogen uplift and associated Mianlue oceanic crust subduction may have begun at the Permian–Triassic transition with a protracted hydrothermal event in the south‐western Ordos Basin. [ABSTRACT FROM AUTHOR]

Saddle dolomite is a Ca–Mg carbonate characterized by curved crystal faces, curved cleavage and sweeping extinction under cross‐polarized light. Saddle dolomite and, generally, Ca–Mg carbonates with curved crystal faces, are often assigned to the burial (hydrothermal) realm and serve as proxy archives for hydrogeochemical processes in sedimentary basins and orogens. At present, the physicochemical conditions leading to the formation of these peculiar warped carbonates are unclear, and the mechanisms inducing the curvature of their crystal lattice are debated. This study uses laboratory experiments to assess the factors controlling the formation of carbonates with curved crystal faces as a function of fluid temperature, reactant size, fluid salinity and fluid Mg : Ca. Results show that a range of magnesium calcites with curved surfaces form at elevated temperatures (ca 220°C) from calcium‐rich fluids (Mg : Ca = 0.43) within a wide range of fluid salinities (5 to 40 wt.%). Magnesium calcites that nucleate epitaxially on rhombohedral or saddle dolomite substrates exhibit warped surfaces, while those that nucleate on calcite seeds form flat surfaces. Although the two crystal habits can co‐occur, Mg‐calcites with curved crystal faces (Mg : Ca of 0.35 to 0.40) tend to be more calcium‐rich than those with flat faces (Mg : Ca of 0.58 to 0.74). In experiments with higher fluid temperature (230°C), calcite reactants undergo replacement by dolomite exhibiting planar crystal faces. The results collectively indicate that the formation of Ca–Mg carbonates with warped surfaces is likely related to a combination of geochemical and physical parameters and various threshold limits, as opposed to one specific parameter, for example, elevated fluid temperature, as is commonly reported in the literature. Although most of the present experimental precipitates are disordered magnesian calcites with bent crystal faces, it is reasonable, at the level of a tentative working hypothesis, that these represent precursors of many ancient saddle dolomites commonly found in burial settings. [ABSTRACT FROM AUTHOR]

The reconstruction of thermal evolution in sedimentary basins is a key input for constraining geodynamic processes and geo-energy resource potential. We present a methodology to reproduce the most important transient thermal footprints accompanying basin formation: lithosphere extension and sedimentation. The forward model solving the transient heat equation is extended with an inversion workflow to constrain models with temperature measurement, providing estimates on model parameters, most importantly the amount of lithosphere stretching. We apply the methodology to the NW part of Hungary. We test the effect of variations in model input parameters on the resulting temperature estimates and discuss the uncertainties and limitations of the modelling technique. Realistic past and present-day temperature predictions for the entire lithosphere are achieved for a carefully assessed set of input parameters, suggesting the strong attenuation of the mantle lithosphere through extension and relatively small variations in the present-day thermal lithosphere thickness. The new temperature model can be used to constrain geodynamic processes and lithosphere structure and rheology, and it can serve as a first-order boundary condition for geothermal exploration. [ABSTRACT FROM AUTHOR]

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The Duvernay Formation of Simonette Block is rich in shale oil and gas resources. The present-day in-situ stress field is a crucial parameter during the exploration and development in this block, a better understanding of which can assist with drilling and completion engineering, fracturing stimulation, and well deployment. In this study, the present-day in-situ stress in the Duvernay shale is predicted and analyzed based on well calculations and geomechanical modeling. The findings indicate that, I, NE-SW-trending is the dominant SHmax orientation. The SHmax and Shmin are the maximum and minimum principal stress, indicating that the Duvernay shale of Simonette Block is under a strike-slip faulting stress regime. II, The present-day in-situ stress in the Duvernay shale is heterogeneously distributed, which is controlled by lithology difference, fault development, and distribution. High stress values in the upper shale member D layer are mainly in the northwestern and central parts of Simonette Block. III, The present-day differential stress in the Duvernay shale mainly ranges from 15 MPa to 30 MPa. Bedding-parallel fractures are relatively developed, aiding in the creation of complex fracture networks. The results are expected to offer geological references for further development of shale oil and gas in the Simonette Block. [ABSTRACT FROM AUTHOR]

Carbon capture and storage (CCS) technology is a crucial and effective tool to achieve China's dual carbon goals. The primary locations suitable for underground CO2 storage include depleted oil and gas reservoirs, deep saline aquifers, and deep unmineable coal seams. Among these, deep saline aquifers are widely distributed in most of the world's sedimentary basins, and they offer significant advantages—such as substantial storage capacity, well-established technology, high safety standards, and cost effectiveness—making them crucial geological reservoirs for carbon dioxide storage. In comparison to foreign countries' projects on CO2 capture, utilization, and storage (CCUS) technology, China's initiatives have been implemented more recently, and no research has been conducted on the geological storage of CO2 in the deep saline aquifers within the study area. In this study, we systematically analyzed the key factors for the geological storage of CO2 in saline reservoirs within the northwest plain of Shandong Province: the Paleogene Shahejie Formation saline aquifer, and the lower reservoir of the Minghuazhen Formation saline aquifer located east of the Zhanhua–Lijin–Dongying line. The CO2 geological storage potential of these aquifers was assessed using the evaluation methodology of the United States Department of Energy, yielding a result of 30.355 billion tons. An evaluation index system of CO2 geological storage suitability was established. Evaluation indices for regions in the study area were assigned according to this evaluation index, and the score and grade of each unit were obtained. The results indicated that the Huimin latent fault depression, Dongying latent fault depression, Dezhou latent fault depression, and Dongming–Shenxian latent fault depression are suitable prospective areas for CO2 geological storage in the saline aquifers of Shandong Province's northwest plain. [ABSTRACT FROM AUTHOR]

We present a fast implementation of a 1D elastic full-waveform inversion for reconstructing the elastic structure of the subsurface. The FWI is an inversion algorithm that directly models the full seismic wavefield by solving a semi-analytical form of the elastic wave equation for a 1D layered earth model known as the reflectivity method. The input seismic data are pre-conditioned anglegathers. The inversion is done using a stochastic algorithm known as PSOES, a fast hybrid stochastic optimization algorithm. Our work primarily contributes to accelerating the computation times required for the inversion, with the goal of developing a strategy that enables code implementation at production scales. Additionally, we are working on creating a framework for conducting joint inversions with potential field data. The computational cost of the FWI is directly proportional to the number of unknowns in the inversion problem, which correlates with the vertical resolution of model (i.e., the layer thicknesses in the 1D Earth model) and the maximum depth of the study. However, the relationship is not linear because increasing the number of unknowns affects the run time of both the forward and inverse problems. On the other hand, the quality of the solution highly depends on the vertical resolution since modeling the higher frequencies in the data requires a relatively small vertical thickness. An optimum implementation of the FWI could result in calculating 1D elastic profiles of the subsurface which could be used for constraining the inversion of potential field data over sedimentary basins. [ABSTRACT FROM AUTHOR]

Abstract\nKEY POINTSThe Proterozoic Birrindudu Basin lacks a robust chronostratigraphic framework and remains one of the least explored basins in the Northern Territory, Australia. It shares lithological and chronological similarities with the McArthur Basin and the Tomkinson Province, which together form the ‘greater McArthur Basin’. The sedimentary successions of these basins have been divided into five basin-scale, non-genetic depositional packages—the Redbank, Goyder, Glyde, Favenc and Wilton packages. Of these, the Favenc Package is among the least studied. The Wattie Group in the Birrindudu Basin is interpreted as part of the Favenc Package based on geophysical and sedimentological correlations. New LA-ICP-MS detrital zircon U–Pb data provide new constraints on the age and provenance of the Wattie Group and establish relationships with the other Favenc Package sequences of the greater McArthur Basin. Our new data, combined with published data, yield maximum depositional ages for the formations of the Wattie Group, from oldest to youngest: the Wickham Formation (1623 ± 24 Ma), the Burtawurta Formation (1591 ± 70 Ma), the Hughie Sandstone (1585 ± 28 Ma), the Neave Formation (1611 ± 18 Ma), the Gibbie Formation (1705 ± 55 Ma) and the Seale Sandstone (1550 ± 24 Ma). The detrital zircon age distribution suggests that the Wattie Group primarily received detritus from south and southeastern regions, which we link to denudation and erosion of a southern orogen during the early Mesoproterozoic. A subtle northward shift in sediment source is apparent in stratigraphically younger units. This age-provenance shift is matched with a similar stratigraphic change in petrography, which we interpret as near-complete denudation of southern orogenic topography and a return to sediment sourced from proximal northern sources. Tectonically, we interpret that the Wattie Group represents erosion of topography caused by the Isan/Chewings Orogeny during the last major Nuna amalgamation.Detrital zircon geochronology in combination with sedimentary petrography helps describe the deposition history of the Wattie Group.Temporal variation in basin provenance provides insights into the tectonic geography of the North Australian Craton during the Mesoproterozoic.The Favenc Package correlative units elsewhere in the greater McArthur Basin have comparable U–Pb detrital zircon spectra to the Wattie Group. [ABSTRACT FROM AUTHOR]

It is essential to intensify research on the strike-slip tectonic system in West and Central Africa to better understand regional tectonic evolution and achieve future breakthroughs in oil and gas exploration. Based on the structural interpretation of extensive seismic data and stratigraphic paleontological analysis of more than 50 wells, this study investigated the tectonic history, sedimentary filling, and evolution of the rift basins in the West and Central Africa, and identified a novel type of intraplate strike-slip tectonic system. It exhibits the following characteristics: (i) the strike-slip tectonic system in the West and Central Africa consists of the Central African Shear Zone (CASZ) and two rift branches, manifesting as an N-shape; (ii) most of basins and rifts are characterized by rapid subsidence at one end and substantial sedimentary thickness; (iii) two types of strike-slip basins are developed, namely the transform-normal extensional basin (TEB) along CASZ and the strike-slip-induced extensional basin (SEB) at each end of CASZ; (iv) two types of basins display their own temporal and spatial evolution history. TEBs underwent two rifting stages during the Early and Late Cretaceous, with a strong inversion at the end of the Late Cretaceous. SEBs experienced three rifting stages, i.e., the Early Cretaceous, Late Cretaceous, and Paleogene, with a weak inversion; and (v) this strike-slip tectonic system was formed under intraplate divergent field, indicating a new type of system. This discovery enhances understanding of the breakup of Gondwana and provides valuable guidance for future oil and gas exploration. [ABSTRACT FROM AUTHOR]

The Yanchang Formation of the Triassic in the Ordos Basin comprises various stratigraphic intervals. The Chang 8 reservoir represents a significant oil-producing section of the Yanchang Formation, and its hydrocarbon accumulation mechanism is complex. In this study, we analyzed the diagenetic evolution and reservoir-forming stages of the Chang 8 member of the Yanchang Formation in the Late Triassic in the Fuxian area, the southern Ordos Basin, via thin-section casting, scanning electron microscopy (SEM), X-ray diffraction, and fluid inclusion petrology and homogenization temperature analyses. The relationship between the petrogenesis and hydrocarbon charging history was analyzed, which provided guidance for identifying and predicting the hydrocarbon reservoir distribution. The results show that the main diagenesis types of the Chang 8 reservoir are compaction, cementation, dissolution, and metasomatism. The comprehensive analysis of the reservoir mineral types, diagenesis, diagenetic sequence, and thermal evolution degree of organic matter shows that the Chang 8 reservoir of the Yanchang Formation is in the A stage of the middle diagenesis stage. Under the overpressure of hydrocarbon generation, oil and gas migrated into the Chang 8 reservoir along fractures and connected pores. The earlier-stage hydrocarbon charging occurred after compaction and later than the early clay film formation and early calcite precipitation, and it also occurred earlier than or simultaneously with the quartz overgrowth. The later hydrocarbon charging occurred after the significant quartz overgrowth and late calcite pore filling. Depending on the homogenization temperature and salinity, the fluid inclusions can be divided into two types: low-temperature, low-salt (90–105 °C, 1.4%–11.2%) fluid inclusions and high-temperature, high-salt (115–120 °C, 2.2%–12.5%) fluid inclusions. According to the analysis of the evolution of the burial history, hydrocarbon charging in the Chang 8 reservoir of the Yanchang Formation in the Fuxian area occurred in two consecutive periods: 133~126 Ma and 122~119 Ma, demonstrating one-scene, two-stage reservoir formation, characterized by simultaneous reservoir densification and hydrocarbon charging. In this research, we precisely ascertained the regional diagenetic characteristics and patterns and periods of hydrocarbon charging, thereby furnishing crucial evidence that deepens the comprehension of sedimentary basin evolution. [ABSTRACT FROM AUTHOR]

(1) Background: The Ordos Basin is one of the sedimentary basins in China that is richest in oil and gas resources. The Chang 7 member of the Yanchang Formation is a set of organic-rich shale, abundant in collophane. (2) Methods: The observation and analysis of rock thin sections, combined with major elements, trace elements, electron probes, and other technical means, the characteristics and genesis mechanism of collophane in the organic-rich shale of the Chang 7 member of the Yanchang Formation in the Ordos Basin were studied. (3) Results: Collophane are divided into oolitic collophane, red-yellow aggregate collophane, and apatite-containing crystalline collophane; the main chemical compositions of the collophane were CaO, P2O5, FeO, Al2O3, and MgO. (4) Conclusions: Phosphorus elements of collophane in the organic-rich shale of the Chang 7 member of the Ordos continental lake basin are mainly derived from the nutrients carried by the volcanic ash sediments around the basin and the hydrothermal fluid at the bottom of the lake. The formation of collophane is divided into two periods: during the sedimentary period, the phosphorus released by the aerobic decomposition of phytoplankton to the mineralization and degradation of organic matter, and the death of phosphorus-rich organisms is preserved in the sediment by adsorption and complexation with iron oxides and then combined with calcium and fluoride plasma to form collophane; during the early diagenesis process, collophane underwent recrystallization, forming a colloidal, cryptocrystalline, and microcrystalline apatite assemblage. [ABSTRACT FROM AUTHOR]

Studies were carried out on Pirallahi, Gurgan-deniz, Khali, Chilov, Janub, Janub-2, Azi Aslanov, Palchig-Pilpilesi, Neft Dashlari, Gunashli, Chirag, Azeri and Kapaz structures in the Absheron-Balkan oil and gas-bearing zone. Paleogene-Quaternary sediments are represented in the section of the sedimentary cover of the Absheron-Balkan zone. The industrially productive oil and gas deposits discovered in this zone are related to the suites of the lower and upper stages of the Productive series (Pliocene). The changes risk of the total thicknesses and sand content of the suites of Productive series in the structures of the study area were analyzed in the direction of four anticlinal zones. To determine the change risk of thickness and sand content of individual suites of the PS and the phase zonation of hydrocarbons corresponding graphs were constructed and analyzed. The graphs are constructed based on average values of thickness and sand content. According to the conducted analyses, the thickness and sand content of the suites of the lower and upper stages of the PS on the Pirallahi-Janub-2, Khali-Neft Dashlari, Gunashli-Kapaz anticlinal zones are increas from the northwest to the southeast along the northeast and southwest limbs. The characteristics of the thickness changes risk of the PS suites show that the tectonic movements and the relief of the basin bottom play a key role in the thickness distribution. Based on the change of sand content in the study area, it can be noted that the paleogeographical conditions in the basin during the formation of PS sediments were quite favorable. The Kapaz structure, located at the southeastern end of the Gunashli-Kapaz anticlinal zone, is similar in geological structure with other folds of the anticlinal zone where it is located. It can be noted that the GaS, PK, PKS, Balakhani suites with gas-condensate-oil bearing in the adjacent fields are also highly promising here. In the Azeri field, which is located in this anticlinal zone, the PKS suite of the Productive series is gas-condensate bearing. The PK and GaS are oil-gascondensate-bearing in the neighboring Chirag and Gunashli fields, so, they are also can be promising here. The complexity level of the folds noted here is different. İt is play a fundamental role in the distribution of oil and gas fields. İt should be noted that longitudinal faults play a key role in the distribution of hydrocarbon accumulations in the fields of Absheron oil and gas region. Due to influence of the transverse faults folds are placed in a stepped form. İt is lead to reshape the oil fields in Pliocene sediments. Regarding the formation of oil and gas deposits, it should be noted that this process is formed as a result of the alternating activity of vertical and lateral migrations. Therefore, in the chain-arranged ascents within the mentioned zone, in the southeast-northwest direction, so, the differential entrapment of oil and gas along up dip is justified. That is, along the Pirallahi-Janub-2 anticlinal zone, gas-condensate deposits are replaced by oil-gas, in turn, the oil-gas deposits are replaced by oil deposits in the southeast-northwest direction. The lower suites of the PS on the Gunashli-Kapaz anticlinal zone are mainly characterized by gas-condensate, and the upper suites are mainly characterized by the presence of oil-gas accumulations. [ABSTRACT FROM AUTHOR]

The New Caledonia Trough is a bathymetric depression extending 2,500 km from New Zealand to the Coral Sea. Sedimentary successions up to 10 km thick are contained in three main sedimentary basins, the New Caledonia, Fairway and Deepwater Taranaki basins. Deepwater Taranaki Basin occupies the head of the New Caledonia Trough adjacent to the well-known Taranaki Basin lying almost entirely within New Zealand's marine territory. The inboard part of Deepwater Taranaki Basin is covered by a dense grid of high-quality 2D and some 3D seismic data and one exploration well, Romney-1, which did not drill the syn-rift succession. The oldest sedimentary rocks drilled by Romney-1 are palynologically dated as Teratan (latest Turonian and Coniacian – 91–87 Ma). While the New Caledonia Trough is generally thought to have been initiated by Late Cretaceous (Campbell and Mortimer 2014; Strogen et al. 2017), this paper examines the evidence for the age of the oldest sedimentary rocks in the Deepwater Taranaki Basin and hence its age of inception and by inference, inception of the New Caledonia Trough to suggest a possible Jurassic age. [ABSTRACT FROM AUTHOR]

This study describes the clay mineralogy of the Lower Cretaceous (Barremian) rocks of the Wessex Basin for paleoenvironmental interpretations. Seventy-four samples were subjected to optical microscopy, scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), and quantitative evaluation of minerals by scanning electron microscopy (QEMSCAN®) techniques. The results revealed an illite-dominated sedimentation in most sections of the basin, with kaolinite, chlorite, smectite and glauconite occurring in subordinate quantities. Inferred paleoclimatic conditions from the clay mineral trends indicates a warm and dry climate, with seasonal precipitation. Kaolinite to illite ratios indicate that more arid climate conditions were prevalent but brief periods of warm and humid conditions were also present. A strong positive correlation between chlorite and tourmaline indicates that excess chlorite may have been contributed from tourmaline-chlorite-schists in a tourmaline-dominated provenance. SEM confirms that most of the clay minerals are detrital in origin but authigenic kaolinite is also present as vermiform and mica-replacive kaolinite which formed during early diagenetic modification from flushing meteoric waters in warm humid climates. This study is significant because it demonstrates the importance of multi-proxy methods for understanding clay minerals within sedimentary basins for interpreting the paleoclimatic conditions of depositional systems. [ABSTRACT FROM AUTHOR]

The mechanisms for the deposition of the Cambrian carbonate sedimentary successions remain controversial. The carbonate‐dominated successions (Stage 3 to Stage 10) are well developed in the North China Craton and they are commonly thought to represent a platform setting because of the flat top. In this study, we propose a new scenarioi, that the Cambrian successions in North China are more likely a carbonate ramp rather than a platform. Detailed sedimentological investigation for the Cambrian rocks in the Yanshan area (Stage 4 to Stage 10) reveals a total of 21 lithofacies which can be grouped into 7 facies associations, including sabkha and mixed tidal flat, shoal, carbonate tidal flat, tidal flat on shoal, protected lagoon, mid‐ramp and outer ramp to shelf basin. Sequence stratigraphy analysis of the Cambrian in the Yanshan area reveals nine third‐order depositional sequences, which shows an overall second‐order transgression. A number of sedimentary characteristics, including the gentle depositional slope, abundant open marine deposits, scattered shoals and microbial mounds, absence of slump or gravity flow sediment, domination of subtidal facies cycles and widespread deposits that formed below the storm wave‐base, indicate that the Cambrian sediments in the Yanshan area were deposited in an intracratonic carbonate ramp depositional system. This intracratonic carbonate ramp includes inner ramp, mid‐ramp, outer ramp and shelf basin facies belts, with the inner ramp exhibiting sub‐facies corresponding to tidal flat, protected lagoon and shoal sub‐facies. Sequence stratigraphy analysis indicates that relative sea‐level changes, corresponding to these nine third‐order sequences, show synchronous with the global sea‐level change across the studied sections. This consistency implies that eustatic sea‐level changes could have been a major factor for the sequence stacking patterns in the Yanshan Area. [ABSTRACT FROM AUTHOR]

For the first time, a high-resolution record of natural events of the Late Glacial and Early Holocene (14150–9730 cal BP) was obtained for the Upper Kama basin based on sedimentary succession in Novozhilovo Lake (Kama–Keltma lowland). The results of the reconstruction of sedimentation setting, based on paleobotanical and sedimentological analyses, as well as radiocarbon dating, are presented. The beginning of formation of the lake was apparently preceded by a period of predominantly alluvial morpholithogenesis, which presumedly corresponded to the Late Pleniglacial. There are four stages in the evolution of the lake basin: the first three were characterized by lacustrine-alluvial sedimentation that was predominantly minerogenic, and the fourth stage was marked by typical lacustrine organogenic sedimentation. The first stage covered the Bølling–Allerød interstadial period from 14 150 to 13 500 cal BP, which was characterized by the accumulation of sand under conditions of high water flow. At the Allerød–Younger Dryas boundary, bioproductivity increased significantly. During the second stage (13 500–12 420 cal BP), water exchange slowed down and organomineral lake sediment formed. The third stage of the transitional sedimentation refers to the Younger Dryas–Early Holocene (12 420–10 700 cal BP). During that time, alluvial inputs predominated, with a decrease in the organic matter content. Finally, the fourth stage of the eutrophic lake (10 700–9730 cal BP) was characterized by a high organic matter content in the sediment and the aleurite fraction increased in the grain-size composition. [ABSTRACT FROM AUTHOR]

This paper investigates the deep-sea morphology and sedimentary processes within the Santa Catarina Plateau and the Vema Channel, prominent features crucial for influencing bottom circulation in the western South Atlantic and regulating the exchange of deep and bottom waters between the Argentine and Brazil basins. The study leverages a unique dataset comprising multibeam data for generating detailed digital terrain models and sub-bottom profiling records, alongside numerical modeling of bottom current velocities (GLORYS12V1 reanalysis). Numerous sediment waves, predominantly cresting mudwaves and mass-wasting deposits associated with steeper sea floor gradients, were identified in the region, aligning with findings from the Argentinian and South Brazilian slopes. The investigation of these features contributes not only to the identification of contourites but also to the enhancement of understanding regarding deep-water circulation within the 3,500-to-4,500-meter range. This depth range serves as a critical transition zone between the Argentine and Brazil basins and plays a pivotal role in elucidating the northward distribution of Antarctic Bottom Water (AABW), an integral component of the Atlantic meridional circulation. In contrast to prior studies that focused on specific regions of the plateau, this research offers a comprehensive overview of the region's morphology and sedimentary processes, thereby advancing comprehension of deep-water circulation dynamics between the Argentinian and Brazilian basins. [ABSTRACT FROM AUTHOR]

Some taxa of belemnites, bivalves, gastropods, and brachiopods, previously unknown in the Russian Far East (except for Eastern Siberia and Northeast Russia), of both Tethyan and Boreal Arctic origin, have been recorded in the Middle Jurassic of the Soloni River (Bureya River basin). In particular, bivalve assemblages were found to increase in abundance throughout most of the Bajocian section at the Soloni River, similar to what is observed in Siberian sections. However, the first appearance of some species of the genus Grammatodon and trigoniids was recorded in this area much earlier than in Siberia. This, combined with a revision of the taxonomic composition of previously recorded fossils, has made it possible to refine the biostratigraphic subdivisions of not only the studied section, but also the uppermost Lower–Middle Jurassic marine deposits of the Bureya Trough as a whole. The age ranges of the local lithostratigraphic units have been refined to a greater degree. It has been established that the Sinkal'tu Formation corresponds to the Upper Toarcian–lowermost Lower Bajocian, the Epikan Formation to the uppermost Lower Bajocian, the El'ga Formation to the Upper Bajocian, and the Chagany Formation to the Bathonian–Callovian. Data on the palynological assemblages identified in these formations are provided. The recent studies of cephalopods and bivalves from Siberia, the Russian Far East, and southern Alaska have led to the development of a refined interregional correlation scheme for Bajocian deposits in these regions. [ABSTRACT FROM AUTHOR]

This article is devoted to the study of the correlation between the location and strike direction of oil and gas accumulations and tectonic faults in the Western South China Sea. The sedimentary basins of Red River, Phu Khanh, Cuu Long, Nam Con Son, Tu Chinh-Vung Mai, and Malay were selected as the study areas. All available geologic information about these basins was collected for analysis. In addition, marine and satellite gravity data and tilt angle of the horizontal gravity gradient method were used to identify new faults. As a result, a close correlation between the spatial position and strike direction of oil and gas accumulations and fault systems has been revealed in these basins. The discovered correlation allows us to take a new look at the genesis and evolution of oil-gas accumulations and fields in the South China Sea region. The method we used can be applied as an effective tool for oil and gas exploration in sea areas. [ABSTRACT FROM AUTHOR]

In the deep-sea, abundant and diverse biological communities tend to occur in areas where combinations of geological, physical and biological processes locally enhance trophic-wide productivity, sustaining aggregations of consumers and top predators. These areas are 'productivity hotspots' and their delimitation should improve the effectiveness of area-based strategies designed to manage human activities and protect the deep-sea. We explored the premise that fishing operations in association with geomorphological features are effective surrogates for delimiting productivity hotspots distribution in the Brazilian Meridional Margin (BMM; 18°S - 35°S; 200 – 3300 m). We described along-slope and across-slope geoforms and related them with catch patterns of fishes, deep-sea shrimps, deep-sea crabs and squids in 23565 fishing hauls conducted between 2000 and 2007. Over 97% of the total catch was obtained in Santos (42.7%) and Pelotas (54.8%) sedimentary basins. In the former, 55.7% of all fishing hauls and 38.6% of the catch were obtained from one of 12 slope geoforms, which covered 22% of the available fishing area. In the Pelotas basin, a shelf break geoform covering 6% of the fishing area concentrated 29.5% of the fishing hauls and 30.2% of the catch. Best fit delta-lognormal Generalized Linear Models (explaining >50% of the total variance) highlighted the positive effect of shelf break embayments of Santos Basin in occurrence and abundance of the pool of species targeted by fisheries. Within these embayments, sectors incurvated and excavated by erosive action of the Brazil Current positively affected abundance and occurrences of fishes and deep-sea shrimps, respectively. The upper slope (300 – 500 m depths) were particularly favorable for fishes and squid concentrations, whereas the lower slope (600 – 800 m depths) increased the probability of deep-sea shrimp catches. We propose that the Santos Basin shelf break embayments host mesoscale and sub-mesoscale productivity hotspots, sustained by biophysical processes promoted by the Brazil Current flow, coupled with biological active transport of pelagic and demersal vertical migrators, some of them targeted by bottom fisheries. We advocate that these are unique features, in the otherwise oligotrophic SW Atlantic subtropical gyre, that should be taking into consideration in regional systematic conservation plans. [ABSTRACT FROM AUTHOR]

The steep northern slopes of Giona Mt in central continental Greece are the result of an E-W normal fault dipping 35–45° to the north, extending from the Mornos River in the west to the village of Gravia in the east. This fault creates a significant elevation difference of approximately 1500 m between the northern Giona footwall and the southern Iti hanging wall. The footwall comprises imbricated Mesozoic carbonates of the Parnassos unit, which exhibit large-scale drag folding near and parallel to the fault. The hanging wall comprises deformed sedimentary rocks of the Beotian unit and tectonic klippen of the Eastern Greece unit, forming a southward-tilted neotectonic block with subsidence near the Northern Giona Fault and uplift near the Ypati fault to the north. These two E-W faults represent younger structures disrupting the older NNW-trending tectonic framework. Fault scarps are observed all along the 14 km length of the Northern Giona fault accompanied by cataclastic zones, separating the carbonate formations of the Parnassos Unit from thick scree, slide blocks, boulders and olistholites. Inversion of fault-slip data has shown a mean slip vector of 45°, N004°E, which aligns with the current regional extensional deformation of the area, as confirmed by focal mechanism solutions. Based on the general asymmetry of the alpine units in the hanging wall, we interpret a listric fault geometry at depth using slip-line analysis and we forward modelled a disrupted fault-propagation fold using kinematic trishear algorithms, estimating a total displacement of 6500 m and a throw of approximately 2000 m. Seismic activity in the area of the Northern Giona Fault includes a magnitude 6.1 earthquake in 1852, which caused casualties, rockfalls and extensive damage, as well as a magnitude 5.1 event in 1983. The expected seismic magnitude is deterministically estimated between 6.2 and 6.7, depending on the potential westward continuation of the Northern Giona Fault beyond the Mornos River to the Northern Vardoussia saddle. The seismic hazard zone includes several villages located near the fault, particularly on the hanging wall, where intense landslide activity during seismic events could result in severe damage to regional infrastructure. The neotectonic development of the Northern Giona Fault highlights the importance of extending seismotectonic research into the mountainous regions of central Greece within the alpine formations, beyond the post-orogenic sedimentary basins. [ABSTRACT FROM AUTHOR]

Cenozoic reservoirs of northern Rovuma Basin, Tanzania, have not yet been characterized in detail. Combined well log patterns and fracture indicators have not been presented before. This work used petrophysical analysis of density, neutron, gamma ray (GR), resistivity and sonic well logs to characterize reservoir zones at the study area. Twelve reservoir zones (A–L) have been identified based on lithological properties and resistivity anomalies. The presence of hydrocarbons in these zones is concluded based on acoustic parameters involving acoustic impedance and ${V_p}$ V p / ${V_s}$ V s ratio, and ∆TC and neutron porosity crossplots. Fractured sedimentary fills in different stratigraphic levels were assessed based on resistivity-logs crossplots. Results show that eleven zones (A–F and H–L) are gas-filled and zone G is devoid of hydrocarbon. We have shown that, in areas with resistivity anomaly, all GR-resistivity combined patterns may be used to indicate hydrocarbon bearing layers except when there is a co-occurrence of funnel-shaped pattern for both logs. Distribution of fractures and hydrocarbons suggest the existence of compartmentalized reservoirs. These reservoirs have been discussed based on a geoseismic model created to support our arguments. Our technique has allowed easier identification of hydrocarbon bearing zones through well Rx. This technique may be applied in other sedimentary basins. [ABSTRACT FROM AUTHOR]

Organic and inorganic paleothermal indicators (vitrinite reflectance‐ Ro%; illite content in mixed‐layer illite‐smectite‐ I% in I‐S) are routinely used to unravel the burial and tectonic evolution of fold‐and‐thrust belts by determining levels of thermal maturity of sedimentary successions and the amount of tectonic overburden currently eroded. However, the reliability of these reconstructions depends on the availability and quality of thermal indicators. We introduce the use of the anisotropy of magnetic susceptibility (AMS) as an additional proxy for thermal maturity estimations in weakly deformed sedimentary successions. Using original and formerly published data from the Northern Apennines, we calibrate a quantitative relationship between the degree of AMS Foliation (ranging from 1.011 to 1.087) and the respective I% in I‐S and Ro% values. For the computed I% values from the I‐S versus F correlation, we recognize that F values ranging from 1 to 1.050 define the early diagenetic zone (I% in I‐S < 60), F values between 1.050 and 1.108 mark the late diagenetic zone (60 < I% in I‐S < 95), while F values > 1.108 indicate anchizone conditions (I% in I‐S > 95). The computed Ro% versus F correlation provides boundaries for the immature and mature stage of hydrocarbon (HC) generation (0.2 < Ro% < 0.8) with F = 1.055 indicating the transition from diagenesis (immature stage of HC generation) to catagenesis (mature stage of HC generation). The proposed model might serve as a tool for reconstructing the burial and thermal evolution of sedimentary units devoid of organic matter or in siliciclastic sediments consisting of a mixture of detrital and diagenetic minerals. Plain Language Summary: To reconstruct the evolution of mountain chains, geoscientists have used organic and inorganic paleothermal indicators, which are, among others, clay minerals and woody frustules. These indicators are used to infer the geological evolution of sedimentary successions in terms of maximum temperature, burial, and exhumation. However, the reliability of the evolutionary geological reconstruction is related to the number of the constraining thermal indicators, which are not always available. In this framework, we introduce the anisotropy of magnetic susceptibility (AMS) as a marker of thermal maturity in sedimentary successions. We present data collected in the Northern Apennines of Italy, which allow us to calibrate a quantitative model based on a linear correlation between the AMS Foliation parameter and paleothermal indicators. This relation may support the reconstruction of the thermal maturity of sedimentary deposits that are characterized by paucity or absence of materials analyzable with other methods. Key Points: We present a new constraint for estimating tectono‐thermal evolution of fold‐and‐thrust beltsWe discuss a calibrated model for a quantitative relation between the AMS Foliation and Ro% and I% in I‐S [ABSTRACT FROM AUTHOR]

The Minle manganese (Mn) deposit is a typical Mn-bearing deposit in the Datangpo Formation in southern China. The metallogenic environment and associated changing processes directly determine the migration, enrichment, and precipitation of Mn. To have a better understanding of the metallogenic structure, magnetotelluric (MT) method was performed to explore the Minle deposit. Electrical spindle analysis of MT data was conducted based on the Swift decomposition and the phase tensor decomposition, and inversion of the transverse-electric (TE) and transverse-magnetic (TM) models was carried out using the Occam inversion method. The results revealed that the main structural strike of the MT section was approximately 37° north to east and obtained the distribution characteristics of the deep electrical properties in the study area. The "concave structure" in the resistivity model is the main geophysical marker for delineating the Mn-ore body. In the metallogenic structure of Mn ore, a "funnel-shaped structure" of the strata was found, which provided favorable space for the percolation and enrichment of Mn deposits. The results of this study will be helpful in improving geophysical prospecting techniques for sedimentary Mn deposits in southern China. [ABSTRACT FROM AUTHOR]

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Valley networks (VNs) on Mars are crucial for understanding the Martian hydrologic and climatic history. However, the limited resolution of remote sensing data hindered the complete identification of Martian VNs, affecting our understanding of the formation and duration of VNs as well as their climatic significance. In this study, we utilized high‐resolution imaging and topographic data to conduct detailed mapping and investigations of the VNs around the northwestern margin of the Hellas basin, the largest impact basin and major sedimentary sink in the Martian southern highlands. We identified a total of 911 VNs with a cumulative length of 32,086.3 km, more than twice that of previous mapping results. Additionally, we analyzed the morphological parameters of VNs, including stream order, sinuosity, junction angle, stream slope, etc., investigated their geomorphologic characteristics, and determined their formation ages. We propose that occasional precipitation and regional groundwater fostered the formation of well‐developed VNs and a "Hellas Ocean" in the Noachian Period. The main fluvial activity occurred during ∼3.9–3.2 Ga. Subsequently, the climate transitioned from warm and semiarid to cold and arid during the Noachian‐Hesperian transition, leading to the evaporation of the "Hellas Ocean." In the Amazonian, some small simple valleys formed during ∼2.1–1.0 Ga with the supply of meltwater associated with obliquity‐controlled glacial processes. These results reveal prolonged fluvial activity in the northwestern Hellas region with diverse water sources under changing climatic conditions, which make the region a very promising candidate for future in situ exploration missions. Plain Language Summary: Valley networks are widely distributed on the Martian surface and provide a significant record of climatic and geologic evolution. Hellas basin, the largest and oldest impact basin in the Martian southern highlands, has undergone extensive fluvial modification, making it an ideal place to conduct investigations on valley networks (VNs). In this study, we identified 911 VNs in the northwestern region of the Hellas basin, and conducted detailed analyses on their morphology and age using high‐resolution imaging and topographic data. The results indicate that the VNs were mainly active from ∼3.9 billion years ago to ∼3.2 billion years ago. Precipitation and groundwater might have been the sources of water carving the valleys. At this period, the climate was warm and semiarid, and subsequently changed to cold and arid. However, at later stages, small valleys can also be formed by meltwater released by obliquity changes. Based on these results, we can find that fluvial activity could have persisted for a long period in the northwestern Hellas region under different climatic conditions, leading to a high possibility for the existence of habitable environments, which makes this area an attractive place for searching for extraterrestrial life and establishing outposts on Mars. Key Points: We identified 911 valley networks in the northwestern Hellas region and conducted detailed geomorphologic and chronologic investigationsProlonged fluvial activity fed by diverse water sources existed in the study region from the Noachian to the AmazonianThe study region underwent a climate change from a warm and semiarid climate to a cold and arid climate during the Noachian‐Hesperian transition [ABSTRACT FROM AUTHOR]

This study investigated the random scattering effect in sedimentary basins with uncertain geotechnical parameters under vertical SV waves using multiplicative dimensional reduction method. The influence of the depth-to-radius ratio of basins and variability of geotechnical parameters on the random scattering effect was explored. The results indicate that the scattering in sedimentary basins significantly amplifies the uncertainty. The variability of displacement amplitude factors of basins is significantly affected by the depth-to-radius ratio of basins, providing a 2- or 3-time difference under high-frequency waves. The coefficient of variations of displacement amplitude factors has a nonlinear amplification relationship with those of geotechnical parameters. [ABSTRACT FROM AUTHOR]

Tight gas sandstone represents a significant unconventional resource extensively discovered across numerous sedimentary basins around the world. Tight sandstone reservoirs are characterized by low porosity, low permeability, variable source material, rapid spatial and temporal changes, poor reservoir properties, and strong heterogeneity. Traditional geophysical methods struggle to meet the demands of exploration and development of these types of reservoirs. This study applies a high-precision comparative approach using well-seismic integration to establish a relative isochronous stratigraphic framework. Based on this framework, extracting seismic properties can effectively predict tight sandstone reservoirs. This paper, focusing on the Penglaizhen Formation in the Luodai Gas Field of the Western Sichuan Jurassic system. This entire process accomplished in three steps: starting with regional marker layers as the initial framework; followed by the establishment of a relative isochronous framework through precise well-seismic integration; and finally stratigraphic slicing techniques to delineate isochronous stratigraphic framework with shorter time intervals. Thereby enhancing the reliability of subsurface stratigraphic information and data accuracy. The study posits that current technological means cannot create a truly isochronous stratigraphic framework; thus, "isochronous" is considered a relative concept in this context. The framework aims to ensure temporal consistency by minimizing discrepancies through mutual constraints between well and seismic data, serving to exploration and development requirements. Furthermore, analyses such as sensitive attribute extraction, impedance inversion, and assessment of hydrocarbon potential in tight sandstone reservoirs demonstrate strong correlation with drilling results. This validation underscores the framework's efficacy in interpreting industrial gas production flows, thereby providing robust support for future oil and gas exploration. [ABSTRACT FROM AUTHOR]

The Carboniferous Benxi Formation in southern Shanxi of North China has significant bauxite resource potential; however, the source of its metallogenic material and its sedimentary environment remain unclear. The microscopy, X-ray diffraction, X-ray fluorescence spectroscopy, and inductively coupled plasma mass spectrometry methods were applied in this study to examine the mineralogical, petrographic, and geochemical characteristics. Geochemical proxies of La/Y, Sr/Ba, Al2O3/TiO2, Zr/Sc, Th/Sc, La/Sc, and Th/Co were analyzed to investigate the paleo-depositional environment and provenance of the aluminum-bearing strata. The findings indicate that diaspores are the primary ore minerals in bauxite, while kaolinite and rutile are the predominant gangue minerals. Both the bauxite and claystone/aluminous rocks exhibit high enrichment in Li, Bi, and U, with relative enrichment in In, Sb, Th, Nb, and Ta. Li is notably concentrated in the claystone/aluminous rocks, reaching up to 1994.00 μg/g, primarily occurring in cookeite and boehmite, while U is highly concentrated in the bauxite. The aluminum-bearing strata were primarily formed under alkaline-reducing conditions, with changes in acidity and alkalinity of the environment during the sedimentary diagenetic process. Marine transgressions significantly impacted the sedimentary environment of the aluminum-bearing strata, and the paleoclimate was characterized as hot and humid. The principal factors contributing to enrichment of aluminum in the sedimentary basin were the in situ weathering of aluminum-rich source rocks and the transport of clastic materials from high-aluminum source rocks. The source rocks were closely associated with intermediate-acidic magmatic rocks and potentially related to the weathering of Ordovician carbonates. [ABSTRACT FROM AUTHOR]

The interaction between the topography of the slope zone on the edge of the basin and the distribution of sediments is crucial for accurately predicting sediment distribution, but few studies emphasize the impact of stratigraphic overlap on the spatial evolution of sedimentary facies. The tectonic movement and sedimentary environment of Hala'alat Mountain in the northwest margin of the Junggar Basin are complex, and the sedimentary model of the whole Cretaceous system is still unclear. This article uses lithology, logging, and seismic data to explain the evolution process and sedimentary model of the Cretaceous system. The significant overlap of Cretaceous strata in the research area has a significant impact on the distribution of sedimentary facies zones and the development of sedimentary systems. Furthermore, this article explores the genesis mechanism of the Cretaceous stratigraphic overlap phenomenon, clearly defines the boundary range of stratigraphic overlap, and deeply analyzes how sedimentary facies zones are distributed and their subsequent evolution trends after the formation of overlap. The results demonstrate that there are apparent stratigraphic overlap phenomena in the second member (K1q2) and the third member (K1q3) of the Cretaceous Qingshuihe Formation in this area. The lithology at the bottom of the formation is grey sand conglomerate with finer grain size in the upper part, and the sedimentary facies are transitioned from fan delta facies to shore shallow lake beach bar facies. In member 1 (K1h1), member 2 (K1h2) and member 3 (K1h3) of the Hutubi Formation, due to the gradual slope and relatively stable sedimentary environment, the distance of stratigraphic overlap becomes shorter, the stratigraphic overlap phenomenon is no longer apparent and the sedimentary facies zone does not change. The study not only reveals the intrinsic relationship between stratigraphic overlap and the distribution of sedimentary facies zones, but also deepens the understanding of the dynamic evolution laws of sedimentary systems. The study on the overlap sedimentary mechanism of the Hala'alat Mountain in the northwest margin of Junggar Basin has reference significance. [ABSTRACT FROM AUTHOR]

The source of uranium is an important research topic related to the exploration of sandstone-type uranium deposits, and potential uranium sources in deep basins are often overlooked. Black organic-rich shale is a common uranium-bearing rock in deep sedimentary basins. However, relatively few studies have investigated the migration of uranium during hydrocarbon generation in and release from uranium-rich shale. In this study, the uranium-rich shale in the Chang 7 member of the Yanchang Formation of the Upper Triassic in the Ordos Basin was selected to investigate the migration of uranium and other trace elements during the thermal maturation of uranium-rich shale via a semiopen pyrolysis simulation system. The gas and liquid products as well as the solid residue were thoroughly analysed by means of multiple instruments. The results showed that uranium significantly migrated before hydrocarbon generation (Ro < 0.61%), with a leaching rate between 12.1% and 18.8%. The leaching rate of uranium during the hydrocarbon generation stage (0.63% < Ro < 1.35%) was relatively low, ranging from 0 to 7.2%. Cu, Pb, Zn, Mo, and other trace elements also migrated considerably during the early stage of thermal evolution, with leaching rates ranging from 2.9 ~ 11.6%. The yield of low-molecular-weight organic acids (LOAs) was the highest in the early stage of thermal maturity, and the LOA yield exhibited a good correlation with the leaching rates of Cu, Pb, Zn, Co, Mo, etc. The generation of LOAs from source rocks was conducive to the leaching and migration of trace elements. Moreover, according to a statistical analysis of published geochemical data, the total organic carbon (TOC) content, uranium content, and U/TOC ratio in shale decreased significantly with increasing burial depth, indicating that uranium migrated significantly upon kerogen hydrocarbon generation during thermal evolution. Therefore, uranium-rich shale is an important deep uranium source in sedimentary basins. [ABSTRACT FROM AUTHOR]

Microbial formation and oxidation of volatile alkanes in anoxic environments significantly impacts biogeochemical cycles on Earth. The discovery of archaea oxidizing volatile alkanes via deeply branching methyl-coenzyme M reductase variants, dubbed alkyl-CoM reductases (ACR), prompted the hypothesis of archaea-catalysed alkane formation in nature (alkanogenesis). A combination of metabolic modelling, anaerobic physiology assays, and isotope labeling of Candidatus Syntrophoarchaeum archaea catalyzing the anaerobic oxidation of butane (AOB) show a back flux of CO2 to butane, demonstrating reversibility of the entire AOB pathway. Back fluxes correlate with thermodynamics and kinetics of the archaeal catabolic system. AOB reversibility supports a biological formation of butane, and generally of higher volatile alkanes, helping to explain the presence of isotopically light alkanes and deeply branching ACR genes in sedimentary basins isolated from gas reservoirs. In this study, the authors use metabolic modelling and isotope labelling to show that archaea can reverse the anaerobic breakdown of butane, turning CO2 back into the gas, which could help explain how some natural gases form providing new insights into Earth's hidden microbial activities. [ABSTRACT FROM AUTHOR]

To improve the security of investors in the petroleum industry and to bestow transparency and reliability to its licensing process, the Brazilian Government has recently implemented a Strategic Environmental Assessment (SEA) to evaluate the potential environmental effects of oil and gas exploration and production activities before the concession of areas. To provide robustness to SEA's analysis stage, this paper aims to propose an innovative methodological approach to map the environmental vulnerability of the area under study, considering selected environmental receptors. This approach combines two techniques, one analytical and the other spatial: environmental risk analysis and spatial analysis. To better illustrate it, this paper presents a case study of the Solimões Sedimentary Basin. Findings show that the approach was able to indicate the more suitable areas inside the SEA region for the development of the O&G upstream activities, as well as to map the vulnerability of each analyzed environmental receptor, to the complete chain of activities, from the exploration for resources until the decommissioning of facilities. This hybrid technique proved to be suitable to the levels of detail required by SEAs and may allow the Government's goals with it to be achievable, including the environmental issues earlier, in its sectorial PPPs. [ABSTRACT FROM AUTHOR]

The Levant Basin of the Eastern Mediterranean accumulated voluminous siliciclastic sediments during the Oligocene–Miocene. The deep‐sea section has attracted significant interest as it contains world‐class hydrocarbon reservoirs ('Tamar Sands Play'). Our recent sandstone provenance study revealed that the hydrocarbon‐bearing, lower Miocene 'Tamar Sands' were recycled from older quartz‐rich sandstones that covered the Arabian flank of the Red Sea Rift. However, sandstones constitute just a third of the thickness of the Oligocene–Miocene siliciclastic section in the Levant Basin, with the rest being mainly composed of shales. Unravelling the provenance of the shale fraction is therefore essential for a comprehensive reconstruction of the Oligocene–Miocene source‐to‐sink system of the Levant Basin. In the present study, we examined the mineralogy and Sr‐Nd isotopes of clay samples retrieved from deep‐sea boreholes that penetrated the Oligocene–Miocene siliciclastic section. The isotopic composition of most clay fractions resembles that of Nile Delta sediments, indicating that unlike the 'Tamar Sands', their dominant provenance lay in NE Africa. Our investigations show that they were derived from Neoproterozoic basement rocks of the Arabian‐Nubian Shield and Tertiary continental flood basalts. The absence of chlorite and serpentine negates detrital contribution from the Arabia‐Eurasia suture in the north. Compilation of the available thermochronology data and major geologic events shows that the accumulation of the siliciclastic section in the Levant Basin coalesced with uplift of the continental areas around the Red Sea. The marked switch to shale deposition recognised in the basin during the late early Miocene signifies the downfall of the 'quartzose' Arabian sediment transport system, when it was partially captured by the evolving Dead Sea Transform valley. Our study highlights the strength of coupling sand and clay provenance investigations in source‐to‐sink studies of sedimentary basins. [ABSTRACT FROM AUTHOR]

Exhumation affects sedimentary basin evolution by influencing structural, pressure and temperature dynamics, thereby impacting energy resource formation. Compaction‐based methods are widely used to quantify exhumation, utilising sonic and porosity data to track sediment uplift from its maximum burial depths. However, uncertainties arise from applying empirical compaction models developed for specific geological regions, highlighting the need for region‐specific models. Even such region‐specific models contain uncertainties, which can compromise exhumation estimates. We, therefore, develop a probabilistic compaction model for the Northwest Shelf Basins using sonic data from normally compacted and unexhumed shales from the Northern Carnarvon Basin (NCB). The model's robustness is estimated using MCMC, and uncertainty propagation analysis is employed to assess the impact of model uncertainty on the model's predictive applications. The model shows exponential porosity reduction with depth, demonstrating rapid compaction from the surface to ca. 2 km and slower compaction thereafter. The model is then applied to interpret new datasets from the Canning, Gippsland and NCB regions. The results reveal that while some parts of the NCB exhibit normal compaction without exhumation, others were significantly exhumed. Conversely, Canning and Gippsland Basin data indicate signs of significant exhumation, as suggested by previous studies, thereby confirming the model's effectiveness outside the Northwest Shelf. Since the model could not explain data from exhumed regions, we inferred new models incorporating "exhumation" parameters to interpret the complex compaction histories of these areas, and the best‐fitting models were selected using the Bayes Factor method. Uncertainty analysis revealed that the impacts of model uncertainty on exhumation estimates are consistent across wide depth ranges. Our findings highlight the need to refine compaction models for better predictive reliability and informed resource exploration in sedimentary basins. [ABSTRACT FROM AUTHOR]