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This review serves as an explanatory note to the sketch map of loessoids, i.e. loess and various loess-like deposits. The map is a byproduct of the ongoing project of Quaternary Map of the Russian Federation, scale 1:2,500,000 in GIS-format. The primary information is derived from the standard National Geological Map scale 1:1,000,000 of the last two generations supplemented by literary data. The map polygons present all mappable loessoid units, including thick southern carbonate loess with paleosols, loess-like silts of northern terrains, intercalations of loessic sediments with waterlain facies and icy silts of the Arctic and Subarctic type. The loessoid formations are classified according to their stratigraphic intervals: 1) the radiocarbon dated Upper Pleistocene of northern terrains, 2) the Middle plus Upper Pleistocene of central Russia, 3) the late Lower Pleistocene to Upper Pleistocene series of southern regions and 4) the Lower Pleistocene red clays of the south. The distribution of diverse loessoids is an imprint of: i) the diverse sedimentary environments of the basically arid periglacial zones of the Pleistocene and ii) the modern geographical zonality changing from subtropics to the icy High Arctic and responsible for post-depositional alteration of subaerial dust. Whatever the origin of the primary dust and geographical varieties of the diagenesis, all loessoids share the same fundamental feature – paleosols, whether numerous and expressive or scarce and weak. They underline the climatically driven intermittent process of loessoid formation – basically subaerial and independent of any aqueous agencies.

In this study statics-based textural analysis GLCM (Grey Level Co-occurrence Matrix) of high resolution L band SAR data from ALOS-2 of JAXA has been used to discriminate between lithological facies of the fold-thrust belt of Nagaland, India. Sandstones, shales, siltstones and clays have been separated in the analysis. Importantly, the lithological facies with second-order compositional variance have been distinguished from each other. The study of 27 lithological pairs indicates a Transformed Divergence index greater than 1.7 except one pair which shows an index of 1.6. The average GLCM texture values of different stratigraphic units in VV and VH polarization shows appreciable differences. Coefficient of variation of the texture samples from each descriptor show uniform distribution around their mean. The mean has thus been used as a lithological index in this study. Further, the medium scaled geological lineaments have been extracted and mapped at 1: 25,000 scale. The Compass Edge Detector on the first Principal Component of full polarized ALOS-2 scene has been used for this purpose. Fracture network, outcrop length, density, and orientation have also been analyzed. The study is successful in rock characterization within vegetation-covered landscape, using L band SAR remote sensing. It may provide an important tool in geological mapping in inaccessible terrains with limited ground data control. The fracture map and its study can provide some useful insights about reservoir characterization and reduce exploration risk in this terrain that has a proven petroleum system.

The first record of the carbonate-hosted Pb-Zn deposits in Turkey dates back to the Roman period. The carbonate-hosted Pb-Zn deposits in Turkey are economically important and found in the Aladaglar - Zamanti Province. Mineral exploration and geological mapping through the utilization of the traditional geological method still remain very challenging in many high terrains (High mountains). In this study, Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) remote sensing data were used for mapping the carbonate-hosted Pb-Zn deposits in the Yahyali region of Turkey. The Band Ratio (BR), Least square fitting methοd (Ls–fit), Band Ratio Color Composite (BRCC), and Principal Cοmpοnent Analysis (PCA) were used tο map the Pb-Zn mineralization zone. The results of this investigation show the spatial distribution of Fe-Mg – OH/CO3, hydroxyl-bearing and iron oxide minerals. Field work and laboratory analysis were carried out to verify the occurrence of alteration zones and highly prospective locations and to confirm the availability of alteration and potential zones of carbonate-hosted Pb-Zn mineralization in the study area. Spatial correlation and distribution were observed between the previous geological map, active and abandoned mines, and the result obtained from the remote sensing data. Different techniques applied to the Aster data image in this study are recommended fοr carbonate-hosted Pb-Zn and lithological mapping in hostile terrains.

This paper presents a review of available lithostratigraphic and isotopic data, in addition to other information collected from projects of the Geological Survey of Brazil (SGB-CPRM), for the Rio Piranhas-Seridó Domain (PSD). This domain is one of the tectonostratigraphic compartments of the central-northeast portion of the Borborema Province (Northeast Brazil), bound by the Picuí-João Câmara, Patos and Portalegre shear zones. More recent isotopic determinations (U-Pb dating of zircon) and geological maps (usually on a 1:100000 scale) have clearly detected and/or redefined several units, e.g., the Amarante, Campo Grande, Granjeiro and Saquinho complexes, in addition to the Serra do Ingá body (Archean), Arabia Complex (Siderian), Caicó Complex and Serra da Formiga Suite (Rhyacian), Poço da Cruz Suite (Orosirian-Statherian), Seridó Group (Ediacaran) and Ediacaran to Early-Cambrian magmatic suites, in addition to pegmatites and granitic pegmatites. With respect to the supracrustal rocks of the Seridó Group, the deposition in the Ediacaran is based on field relations and on the ages of detrital zircons, which showed a greater contribution from Mesoarchean to Neoproterozoic sources, the vast majority of which may come from the PSD itself. Current records indicate that the evolution of the PSD started in the Eoarchean, and peaked in the Neoproterozoic with the Brasiliano event, which is characterized by sedimentation of the Seridó Group, intrusion of plutonic bodies, deformation and metamorphism (especially at the regional level), in addition to the formation or reactivation of important shear zones. Such evolution is acknowledged on the basis of the accretion of oceanic arcs during the Paleoproterozoic (containing Archean fragments), including the generation of juvenile magmas and a protocrust (Caico Complex). The Neoproterozoic record, associated with the Brasiliano event, is considered by several authors as reworking with no or little contribution of juvenile material, with deposition of the Seridó Group, emplacement of several Ediacaran to Early-Cambrian magmatic suites, accompanied by the formation of shear zones, predominantly in the southern and eastern portion of the domain.

A 1:12,000 geological map of the Macao Special Administrative Region has been produced through detailed field work supported by petrographic, mineralogical, geochronological and geochemical data obtained in previous studies. This map aims to represent a reliable tool to understand the geological evolution of the region and for management of the territory. The geology of Macao is dominated by two groups of Jurassic granitic rocks belonging to an intrusive suite located along the coast of Southeast China: Macao Group I (MGI: 164.5 ± 0.6 to 162.9 ± 0.7 Ma) and Macao Group II (MGII: 156.6 ± 0.2 to 155.5 ± 0.8 Ma), including the associated microgranite, aplite and pegmatite dikes and quartz veins. Remnants of the metasedimentary wall-rock are present as Devonian xenoliths enclosed within the granites. Younger Jurassic to Cretaceous andesite to dacite dikes (150.6 ± 0.6 to

The multispectral image, of Landsat 7 and 8; Aster and Sentinel-2A, has good results in lithological, structural, hydrothermal and mineralogical alteration mapping. Segmentation and image classification are two complementary steps as they are allowed the most important operations in the field of image processing. In this sense, this work aims at evaluating the potential of segmentation and classification algorithms for the generation of surface geological maps, hydrothermal alterations and lineaments. Given the good resolution of the Sentinel 2A (10m), the three images, (11/12; 11/2; 11/8), 12.8.2, main component 1, 2 and 3 (11.12.2), processed by five algorithms (K-means, isodata, watershed, efficient graph-based image segmentation, thresholding) for geological mapping and then mining exploration. The study displayed that 1) Watershed algorithm can be used for topographic and hydraulic studies, it can be very useful in the preparation phase of geological and mining infrastructures; 2) threshold segmentation does not give good results in terms of geological discrimination since it divides each image into two parts; 3) the same thing for the effective thresholding and segmentation of graph-based images; 4) The Isodata and K-means algorithms show good geological discrimination.

We present a 1:7500 scale geological map of part of the footwall of the south verging Belluno Thrust of the seismically active eastern Southern Alps of northern Italy. We report a previously unknown thrust zone, the “San Donato-Costa Thrust Zone”, that cuts across the local Meso-Cenozoic stratigraphic succession. 1:2500 and 1:5000 geological mapping, in combination with the revision and improvement of the local lithostratigraphy and detailed structural analysis, provided new insights into the thrust geometry and the setting of the greater area it deforms. We show that the recorded deformation style (e.g. folding vs. faulting) exhibits notable variations within the affected Meso-Cenozoic stratigraphic succession, with shortening accommodated by fold trains and several subparallel thrust splays with variable amounts of stratigraphic offset cumulated during repeated faulting. Our results contribute to a better definition of folding and faulting within the Mesozoic carbonate multilayer system of the eastern Southern Alps.

We document the tectonic and metamorphic evolution of thrust nappes of the eastern island of Elba. The area exposes a natural cross section of the Northern Apennines hinterland, from the metamorphic basement units to the overlying continent- and ocean-derived nappes. We integrated mapping, analysis of structures and microstructures, and the interpretation of drill core logs with lithostratigraphic, metamorphic, and geochronological constraints, producing a novel geological map of eastern Elba (1:5’000 scale). We show that the area experienced polyphase Oligocene – Pliocene contractional tectonics marked by in-sequence and out-of-sequence thrusting accompanied by folding and overprinted by faulting in the Pliocene. Magmatism occurred during contraction with post-magmatic thrusting ultimately coupling HP-LT and LP-HT units. Drill core logs allow for the first time the reconstruction of the N-dipping character of the Zuccale Fault, which represents the youngest (late Miocene – early Pliocene) large-scale structure in the area.

This study uses remote sensing technology and GIS technics for structural study of the Haut-Nkam division with the aim of mapping the lineaments that can significantly influence all geo-structures by identifying major geological features and comes out with a new major structural map. Two methods are used: (i) the spatial reclassification of satellite images LANSAT 7 ETM + and 8 OLI/TIRS; and (ii) the application of band ratios. The confirmation of the structural features (faults, fractures and tectonic directions) is made by (i) a wide variety of digital image processing techniques such as (a) Composite bands and color composition filtrations; (b) Principal Component Analysis (PCA); (c) lineaments density map filtration: (ii) the superposition of the lineaments with the geological maps of each Subdivision and district of the study area. A total of 578 lineaments have been identified following the major directions of NE-SW, NNE-SSW, ENE-WSW, ESE-WNW and E-W with a total length of about 2273 km. These lengths vary from 38.11 to 128.08 km with an average length of 58.87 km. Major lineaments are identified in the six sub-divisions (Bana, Kekem, Bandja, Banka, Bakou, Bafang) and district (Bawa) of the Haut-Nkam division with a majority concentrated at Bakou followed by Bandja and finally Kekem. These major structural deformations identified which could be eminent faults, breakage, or tectonic direction, etc… could have hydrological or hydrogeological implications.

The present work focuses on using remote sensing techniques and geographical information system (GIS) to automatically extract lineaments in the southeast of Morocco, which is one of the most important segments of the Moroccan Atlas system, especially between the southern border of the Central High Atlas and the northern part of the Anti-Atlas. For this purpose, we used Landsat 8 OLI multispectral image processing and the mosaic of two ASTER GDEM images covering the field of study. To achieve this objective, basic pre-processing was applied to our satellite images for the automatic extraction of lineaments, by applying the mathematical algorithm Line Module of the software Geomatica 2016 of PCI. The processing used included principal component analysis (PCA), shading at different angles of the GDEM, and 7 × 7 matrix directional filters, followed by the extraction of the lineament steps. The lineament extraction obtained results from the PC1 image, derived from the panchromatic band satellite image and the GDEM, proving that each produced map had a strong similarity in terms of concentration and orientation in two major directions: WSW-ENE and SW-NE, with a concentration of these lineaments in the northeastern part of the southern part of the Central High Atlas. This concentration was also clearly observed in the southeastern part at the Precambrian bedrock of Saghro. The results obtained from the automatic extraction of the lineaments revealed 18,450 lineaments, with sizes varying from a few meters to 7.5 km, with an average length of 902 m. The lineaments of small extensions were the most numerous, having intervals included between 458 and 2972 m. The projection of these lineaments on a directional diagram revealed a predominance of the NE-SW direction. To improve our results, multisource data such as the mosaic of two geological maps at a scale of 1:100,000, covering the complete study area, as well as a calibrated high-resolution field imagery backgrounds from the environmental systems research institute (ESRI) were used to validate our automatic lineament mapping results. As a conclusion of this investigation, we discovered that the automatic extraction provides a more accurate means of mapping structural lineaments, showing a good accordance with and more information than previous geological data, and confirming the efficiency of the techniques applied in geological studies.

This research was carried out to understand the nature of strike-slip Jhelum Fault zone and to propose a model for the surface to subsurface deformation pattern. Field data along with satellite images are used to construct the geological map. Moreover, the subsurface model has been proposed using the mechanism of dip-isogons in computer application which connects points of equal inclination or dip on the outer and inner bounding surfaces of a folded layers. The proposed geological map and subsurface model shows that the Jhelum Fault when propagated in the south from Hazara-Kashmir Syntaxis forms a continuous shear zone on surface with some discontinuous exposure of splay faults rather than exposed as continuous discrete break. Likewise, the subsurface cross sections show that deformation along the fault zone is accumulated by splay faults from the main Jhelum Fault, which forms a positive flower structure with steep north-eastward dips, which is characteristics of strike-slip movement along Jhelum Fault Zone. The vertical stratigraphic throw along these faults shows small offsets and little east–west shortening, indicating that the major slip along the fault is strike slip.

The characterization of shallow subsurface formations is essential for geologic mapping and interpretation, reservoir characterization, and prospecting related to mining/quarrying. To analyze elastic and electromagnetic (EM) properties, we characterize near-surface chalk formations deposited on a shallow seabed during the Late Cretaceous-Early Paleogene (Maastrichtian-Danian). EM and elastic properties, both of which are related to mineralogy, porosity, and water saturation, are combined to characterize the physical properties of chalk formations. We also perform rock-physics modeling of elastic velocities and permittivity and analyze their relationships. We then use measured ground-penetrating radar and P-wave velocity field data to determine the key model parameters, which are essential for the validity of the models and can be used to evaluate the consolidation degree of the rocks. Based on the models, a scheme is developed to estimate the porosity and water saturation by combining the two rock-physics templates. The predictions are consistent with previous findings. Our templates facilitate fast mapping of near-surface porosity and saturation distributions and represent an efficient and cost-effective method for near-surface hydrologic, environmental, and petrophysical studies. In the current formulation, the method is only applicable to rock type (chalk) comprising a single mineral (pure calcite). It is possible to tailor the formulation to include more than one mineral; however, this will increase the uncertainty of the results.

Remote sensing technology has advanced significantly, making it useful for geological applications such as structural and lithological mapping, as well as mineral prospecting and mapping. This study looks at how certain enhancement techniques on Landsat 7 ETM+ data can be used to map surface geology, resulting in color composite imagery that can be interpreted and validated through field mapping exercises. Because some of these rocks are poorly exposed and some portions of the research region are inaccessible, field mapping was supplemented by remote sensing lithological mapping techniques. False Color Composite images for bands (7:4:1 and7:5:4), Principal Component analysis (PC1, 2, 3 and PC4, 5, 6) and RGB composite images of Landsat band ratios (1/3:5/7:3/5 and5/1:5/7:4) proved useful in determining the approximate boundaries of the various lithology in the research area. Gneiss and quartzites occur in the central and western quadrants of the study area, mylonites and schist in the eastern quadrant, and amphibolite in the southern and southeastern quadrants, according to GPS sample locations of the individual rock types found in the study area plotted on the processed images. The contact relationships between these rocks are mostly gradational and interlayered. As a result, a thorough examination of satellite optical imagery, such as Landsat data, can greatly aid lithological inquiry and the creation of more detailed geological maps in areas that are inadequately understood.

Flownets, geo-electric layers construction and groundwater exploration analysis was investigated in the eastern and Western parts of Ilorin of Southwestern Nigeria. Apata-Yakuba, Eleko-yangan, Tepatan, Oke-Andi at the Eastern part and Akamo, Idi-Araba in the Western part of Ilorin were surveyed to depict the exact locations for potential future groundwater exploration. A preliminary step to collect lithologs of wells from the records of Nigeria Hydrological Services Agency used 35 water samples taken from hand dug wells and boreholes. Static water levels, total depth and coordinates of hand dug wells were measured using tape and GPS respectively. The Static water level (below ground surface and above sea level) values and their coordinates were processed using IPWIN resist software to generate the water level locations on topographical contour maps and the groundwater flow net of the study area. Result reflects the presence of crystalline rocks consisting of migmatite gneiss, granite gneiss, quartzite and granite. Analysis and interpretation of flownet shows ascending equipotential lines at the Eastern part indicating an easy groundwater movement, and divergent equipotential lines at the Western part indicating difficulty in water movement in the study area. The static water levels values together with the corresponding coordinates were superimposed on the geological map of the study area. This research reveals the water table is very close to ground surface in Oyun, Oke-Andi resulting into digging of shallow wells by the dwellers of the area. Water table is also far away from the surface in places Tepatan, Apata-Yakuba among others

The issues of import substitution of geoinformation systems used in the geological industry when creating sets of State geological maps of the scale of 1:1,000,000 and 1:200,000 are considered. The current state of the issue is described. Additional functionality is indicated, which is necessary for the construction and preparation for publication of digital models of the maps of the set. Examples of domestic GIS are given, which can replace the foreign analogues in use. The problems and difficulties arising in this case were revealed. The ways of their solution are suggested.

O estado de São Paulo apresenta alta complexidade litoestrutural e seu mapeamento é relativamente recente e, em muitos trechos, de pouco detalhe. Este trabalho teve como objetivo principal aprimorar a qualidade dos mapas geológicos anteriores da região de Mococa, São Paulo, com base em levantamentos geológicos e geofísicos (susceptibilidade magnética — SM e gamaespectrometria de potássio — K, urânio — U e tório — Th). Para isso, foram realizadas em campo observações geológicas e medidas da SM e de gamaespectrometria em 189 pontos de amostragem. Os resultados geofísicos, aliados às observações de campo, possibilitaram a elaboração de um mapa geológico, em escala 1:100.000. Esse mapa delimita cinco litologias principais: arenitos e diamictitos, diabásios, siltitos avermelhados, argilitos ricos em K e aluviões recentes. Comparando com o conhecimento geológico da região, essas unidades referem-se, respectivamente: à Formação Aquidauana, à Formação Serra Geral, à Formação Tatuí, à Formação Corumbataí e a Aluviões Quaternários. A comparação dos resultados com os mapas geológicos do estado de São Paulo já existentes indica que os diabásios, que antes ocupavam cerca de 3,1% da área, passaram a ocupar 22,3% por meio do mapa de maior detalhe. A compilação dos valores de SM e de concentração de K, eU e eTh permitiu reavaliar o volume e a distribuição das seguintes unidades: Formação Aquidauana, Formação Tatuí, Formação Corumbataí, Formação Serra Geral e Aluviões Quaternários dos rios Pardo e Canoas. O estudo, portanto, contribuiu para o entendimento de um trecho setentrional da borda leste da Bacia Sedimentar do Paraná, onde os estratos repousam inclinados sobre o embasamento cristalino Pré-Cambriano.

The Litang fault is a left-lateral secondary shear zone in the Sichuan-Yunnan active block that accommodates the tectonic deformation associated with the eastward extrusion of the upper crust of the Tibetan Plateau. Based on 1: 50 000 geological mapping of active faults, the Litang fault consists of three geometric segments, the Cuopuhu, Damaoyaba, and Litang segments, in the west of Litang, which are divided by the of Haizi Mountain uplift and the wide-angle bending and branching of the fault near Jinchanggou. This study also identifies the surface rupture of the A.D. 1890 earthquake, which is distributed intermittently along the ∼28 km long Damaoyaba segments and ∼25 km long Litang segments. The maximum horizontal displacement is 4.1 m along Damaoyaba segments, and 4 m along Litang segments. The rupture involves typical left-lateral shear movement. The two ruptures are divided by discontinuous segments or gaps that are ∼18 km long; thus, the total surface rupture is approximately 71 km long. The estimated moment magnitude was Mw7.3±0.1. A comprehensive analysis of data obtained from 5 trenches excavated along the Damaoyaba and Litang segments and the trench data by Xu et al. (2005) identifies age constraints of the 4 most recent paleoseimic events occurred B.C. 1468±54–1340±25, B.C. 52±25–A.D. 76±47, A.D. 1115±90, and A.D. 1890, respectively. The recurrence intervals are 1 415±80, 1 104±104, and 775±90 a, which are consistent with quasi-periodic earthquake recurrence behavior. The average recurrence interval is 1 098±112 a.

The Covid-19 pandemic occurred at a time of major revolution in the geosciences – the era of digital geology. Digital outcrop models (DOMs) acquired from consumer drones, processed using user-friendly photogrammetric software and shared with the wider audience through online platforms are a cornerstone of this digital geological revolution. Integration of DOMs with other geoscientific data, such as geological maps, satellite imagery, terrain models, geophysical data and field observations, strengthens their application in both research and education. Teaching geology with digital tools advances students' learning experience by providing access to high-quality outcrops, enhancing visualization of 3D geological structures and improving data integration. Similarly, active use of DOMs to integrate new field observations will facilitate more effective fieldwork and quantitative research. From a student's perspective, georeferenced and scaled DOMs allow for an improved appreciation of scale and of 3D architecture, which is a major threshold concept in geoscientific education. DOMs allow us to bring geoscientists to the outcrops digitally, which is particularly important in view of the Covid-19 pandemic that restricts travel and thus direct access to outcrops. At the University Centre in Svalbard (UNIS), located at 78∘ N in Longyearbyen in Arctic Norway, DOMs are actively used even in non-pandemic years, as the summer field season is short and not overlapping with the Bachelor “Arctic Geology” course package held from January to June each year. In 2017, we at UNIS developed a new course (AG222 “Integrated Geological Methods: From Outcrop To Geomodel”) to encourage the use of emerging techniques like DOMs and data integration to solve authentic geoscientific challenges. In parallel, we have established the open-access Svalbox geoscientific portal, which forms the backbone of the AG222 course activities and provides easy access to a growing number of DOMs, 360∘ imagery, subsurface data and published geoscientific data from Svalbard. Considering the rapid onset of the Covid-19 pandemic, the Svalbox portal and the pre-Covid work on digital techniques in AG222 allowed us to rapidly adapt and fulfil at least some of the students' learning objectives during the pandemic. In this contribution, we provide an overview of the course development and share experiences from running the AG222 course and the Svalbox platform, both before and during the Covid-19 pandemic.

The COVID-19 pandemic hindered the ability to conduct field geology courses in a hands-on and boots-on traditional manner. In response, we designed a multi-part virtual field module that encompasses many of the basic requirements of an advanced field exercise, including designing a mapping strategy, collecting and processing field observations, synthesizing data from field-based and laboratory analyses, and communicating the results to a broad audience. For the mapping exercise, which is set in deformed Proterozoic crystalline basement exposed in the Front Range of Colorado (USA), student groups make daily navigational decisions and choose stations based on topographic maps, Google Earth satellite imagery, and iterative geological reasoning. For each station, students receive outcrop descriptions, measurements, and photographs from which they input field data and create geologic maps using StraboSpot. Building on the mapping exercise, student groups then choose from six supplements, including advanced field structure, microstructure, metamorphic petrology, and several geochronological datasets. Because scientific projects rarely end when the mapping is complete, the students are challenged to see how samples and analytical data may commonly be collected and integrated with field observations to produce a more holistic understanding of the geological history of the field area. While a virtual course cannot replace the actual field experience, modules like the one shared here can successfully address, or even improve on, some of the key learning objectives that are common to field-based capstone experiences, while also fostering a more accessible and inclusive learning environment for all students.

In recent years, the analysis of satellite gravity data is used as a powerful tool for geologic mapping. This study is based on various filtered maps of Bouguer gravity anomaly data of the Southwes...

International audience; We present and discuss the results of a field-based approach including accurate geological mapping and micro-to map-scale structural analysis to highlight the finite strain pattern recorded in Marguareis Unit, a massif deformed at shallow crustal levels at the boundary between Maritime and Ligurian Alps. We describe superposed tectonic structures developed under low-grade metamorphic conditions during the Alpine collision and nowadays exceptionally well recorded in the area of interest. We demonstrate that the structural frame of the Marguareis Unit results from superposition of fourfold systems, later segmented, but without significant displacements, by brittle faults.

The geological map of the old western region of Nigeria indicates the presence of iron ore deposit at Iboro village Ogun state (7.9983o - 7.99933o N, 3.5790o - 3.5890o E). Hence a ground magnetic survey was carried out at a location at Iboro village so as to delineate the subsurface magnetic anomalies and to know whether the anomalies favour accumulation of magnetic minerals. The survey was carried out using high resolution proton precession magnetometer model G-856X. Eight traverses were run at 5m separations and earth magnetic intensity values were measured at 10m intervals along each traverse; the acquired data were corrected for drift. The residual anomalies obtained by removal of regional gradient from observed data using trend analysis were presented as profiles and maps. The treated data were qualitatively and quantitatively interpreted and the results gave values for the total ground magnetic anomalies that varied between a minimum and maximum peak values of about -33.0 and 30.6nT respectively. Depth to the basement rock was estimated using Peter’s half slope method which gave a maximum depth of about 13m. The contour maps and the total relative graphs present the subsurface picture of the geological structure that is assumed to harbour the metallic minerals through the action of the field towards the concentration of anomalies. It was suspected that the overburden was relatively thin in the study area and the minerals were at a shallow depth.

WorldView-3 (WV-3) is the first high spatial resolution and super-spectral commercial satellite which has the capability in improvement of geological mapping. The VNIR-SWIR data of this satellite are evaluated in this study for mapping the lithological units of a metamorphic-igneous terrain in Chadormalu area, Central Iran, by the use of support vector machine (SVM) classification method. Applying principal component analysis (PCA) as an image transformation technique on the WV-3 data, and interpretation of its results, supported by field observations, petrography, and spectroscopy, lead to identifying training areas which are input to the SVM algorithm. This method not only produces a detailed lithological map of all exposed rock units, but also well discriminates diorite-gabbro diorite from granite, and gneissic granite from green schist and garnet mica schist, which are not revealed in 1:100,000 geological map of the area, published by Geological Survey of Iran (GSI), with overall accuracy of 88.36% and the Kappa coefficient of 0.86. Furthermore, the efficacy of each applied band of WV-3 is assessed in promoting classification accuracy using SVM method. Results show that band 7 of SWIR region has increased the overall accuracy 4.81% relative to SWIR dataset, and improves the classification accuracy of green schist and diorite. Moreover, bands 5, 6, and 8 of SWIR dataset are more efficient in improvement of the overall accuracies than other bands. This study concludes that WV-3 data provides a good facility to generate large scale geological maps owing to its high spatial and radiometric resolution and appropriate SWIR bands.

This study combines historical exploration data with new mapping, underpinned by airborne hyperspectral imagery, to provide a detailed camp-scale geologic view of the Rössing uranium mine area in the Damara orogen, Namibia. The Neoproterozoic Damaran metasedimentary host rocks to uranium deposits of the Rössing area structurally overlie Paleoproterozoic basement rock. Both units were subjected to polyphase deformation and upper amphibolite to lower granulite facies metamorphism during Pan-African orogenesis. The sequence was voluminously intruded by leucogranites, where younger phases may contain ore-grade uranium as magmatic uraninite and traces of betafite, together with secondary uranium minerals. Early, postdepositional modifications to the Damaran sequence included partial dolomitization of marble units and development of evaporite dissolution and diapiric breccias. Major pre-D3 extensional structures developed in conjunction with recumbent, isoclinal folding and acted to focus the intrusion of early, mostly barren leucogranites generated primarily through anatexis of Damaran metasediments. Syn-D4 leucogranites overprint complex interference fold geometries that resulted from D3 deformation. D4 leucogranites were emplaced under predominantly ductile, transtensional conditions, into NNE-trending zones oriented highly oblique to all preexisting structures. These steeply dipping zones provided the prerequisite conditions for partial melt material to be derived from uraniferous basement lithologies. The concentration of magmatic uranium was promoted where leucogranite melt material interacted with carbonates and sulfide-bearing Damaran metasedimentary units. In the Rössing area these horizons occur at the Khan-Rössing Formation contact zone for the SJ, SK, SH, Z20, and Husab deposits and within and above the Arandis Formation for the Z19 deposit leucogranites.