scholarly journals Horizontally deplacement geomasses in the continental rift geostruсtures (on the example of the Dnipro-Donets paleorift). Part 2. Structural parageneses of the reid deformation of the sedimentary cover

2019 ◽  
Keyword(s):  
Sedimentary Basin ◽  
Sedimentary Cover ◽  
Regional Scale ◽  
Strike Slip ◽  
Practical Significance ◽  
Tectonic Activity ◽  
Geodynamic Setting ◽  
Secondary Deformation ◽  
Linear Slope ◽  
Horizontal Displacements

Formulation of the problem. The inversion stages of the structural-material evolution of the continental crust are characterized by regional scale of the deformation of volume tectonic flow of platform sedimentary rocks, which caused significant horizontally-healthy movements of tectonically activated geo-mass in the intra-plate graben-rift. The dynamic deformation of geomases manifests itself at the final stages of the geological development of such structures; therefore, it determines the main features of the systemic organization of the modern architecture of the basement and sedimentary cover complexes. Review of previous publications and studies. Secondary deformation linear slope, according to Patalakha E. (1979); Alekseev V. (1990) is considered as a set of local strike-slip zones, formed on spherically-located viscous faults, forming joint tectonic flows. The structural skeleton of tectonic flows, as the basis of the tectonic dislocation process, make offsets with the horizontally and rotational component movements. Horizontal landslides are typical disjunctive elements of the continental structures formed in the geodynamic conditions of the transtension (grabens, rifts), transpression (folded mobile belts, intra-plate activation zones), as well as the basic structural elements of the strike-slip tectonics of the sedimentary basin. The purpose of the article. The second part of the trilogy continues regional geotectonic studies of post-rift complications of the sedimentary cover structure of Dnipro-Donets Paleorift (DDP), covering the three main stages of the platform tectonic activation. Late Hercynian epoch was characterized by the formation of large linear anticlinal zones and salt-shafts against the background of the general syneclizal deflection of sedimentary basin, located within the paleorift. Cimmerian epoch of tectonic activity led to significant thrust deformations of the primary structural forms of the cover in the geodynamic setting of collision compression with intensification of the horizons of the sedimentary cover. The structural manifestation of strike-slip tectonics at Alpine epoch in sedimentary complexes are mainly horizontal displacements of geomases of blocks, lineaments, local tectonic elements and structures along dynamically interconnected coulisse of strike-slip domains. Methods. Structural kinematic analysis of transformations of the fracture systems of the Upper-Visean sedimentary complex under the influence of natural mechanism of reid tectonic flow of rocks. Results. The secondary structures of strike-slip deformation, structural kinematic parageneses, dislocations zones and subregional structural waves were identified in the structure of the platform cover, which are natural geological objects formed at the inversion stages of geological development of DDP. Scientific novelty and practical significance. The result of structural manifestation of volume tectonic flow in the platform complex was horizontal displacements of the original tectonic elements, blocks, segments, structures along dynamically-linked strike-slip domains. This is caused by the formation of secondary deformation structures of various scales, morphology and genesis, which comprise longitudinal structural waves of strips of post-rift deformations in the structure of the sedimentary cover of DDP.

Structural evolution and sedimentary record of the Stephano-Permian basins occurring beneath the Mesozoic sedimentary cover in the southwestern Paris basin (France)

2015 ◽  
Vol 186 (6) ◽  
pp. 429-450 ◽  
Author(s):  
Laurent Beccaletto ◽  
Laure Capar ◽  
Olivier Serrano ◽  
Stéphane Marc
Keyword(s):  
Structural Control ◽  
Sedimentary Cover ◽  
Initial Period ◽  
Structural Evolution ◽  
Strike Slip ◽  
Seismic Facies ◽  
Tectonic Activity ◽  
Paris Basin ◽  
Thickness Variations ◽  
Seismic Lines

AbstractStephanian to Permian post-orogenic basins (SPB) outcrop in several limited locations in and around the present-day French Variscan basement. Little is known about their subsurface occurrences beneath the post-depositional sedimentary cover. Our work intends to decipher the structural evolution of the hidden SPB in the southwestern Paris basin, where only a few regional studies have aimed to determine their location beneath the Mesozoic sedimentary cover.Our approach is based on the reprocessing and interpretation of 36 seismic lines (1480 km) acquired by the oil industry in the 1980s in the southwestern Paris basin. We first obtain a comprehensive view of the geometry of the SPB, based on (i) the interpretation of the base of the Stephano-Permian surface (lower limit) and the erosional base of the surface of the Triassic layers (upper limit) and (ii) the recognition of specific internal geometries and seismic facies. The interpreted faults are grouped into different categories according to their period of activity, with a focus on synsedimentary faults related to thickness variations of the Stephano-Permian deposits. We then propose a structural scheme containing faults that were active during the Stephano-Permian period, in relation to the late-Variscan structural pattern which has led to the recognition of five sets of faults: N140-trending faults associated with secondary N155- and N055-trending faults (Arpheuilles basin); N115-trending faults (Contres basin); N030-trending faults (Brécy basin); NS-trending faults (transition between the Contres and Brécy basins). Based on the seismic interpretation, thickness maps are calculated both in time and in meters, allowing a pseudo-3D view of the three identified SPB, with thicknesses up to 3000 m (Contres basin); these maps indicate that the preserved extents and thicknesses of the basins in the subsurface are systematically greater than those observed at outcrop.Finally, we show that the SPB were filled during two different tectonic phases: (i) an initial period of opening of the Arpheuilles, Contres and Brécy basins, during which Stephanian conglomeratic/coal facies were deposited under a strong structural control (normal faulting with certainly a strike-slip component, wedge-shaped geometry of the sediments); (ii) a consecutive pre-Triassic tectonic activity (N155-trending strike-slip in the Arpheuilles basin, uplift of the margins of the three basins), at the origin of a significant part of the sedimentary filling of the basins; this vertical uplift may have reached 2000 m.

scholarly journals Colisional deformations of the Dnieper-Donets Basin. Part 2. Geodynamic modes and kinematic mechanism of tectonic inversion

2020 ◽  
Vol 15 (4) ◽  
Author(s):  
A.V. Bartashchuk ◽  
Keyword(s):  
Sedimentary Cover ◽  
Kinematic Model ◽  
Strike Slip ◽  
Donets Basin ◽  
Geodynamic Setting ◽  
The West ◽  
Late Mesozoic ◽  
Tectonic Inversion ◽  
Orogenic Uplift ◽  
Kinematic Mechanism

The tectonic inversion of the Dnieper-Donets Basin and the Donets Foldbelt began in the Late Hercynian epoch under the influence of collisional movements of the left-sided knematics of the compression orogen on the edge of the Paleotethis. It is shown that as a result of gently inclined disruptions in the Paleozoic platform cover of the West Donets Graben, a thrust lattice was formed, which controlled the processes of collisional buckling of the horizons in the thrust and strike-slip modes. As a result of the displacement of geomasses from the axial zones of maximum compression to the zones of "geodynamic shadow" - in the direction of the Basin borders in the northern and axial parts of the Graben, linear uplift folds were formed, and in the southern - thrust covers. At the Late Mesozoic and Cenozoic, in the mode of interference of the uplift-thrust and strike-slip fields of the reverse, right-sided kinematics of movements, deformations of the Hercynian thrust lattice and the dynamically conjugated linear near-fault folding took place with the formation of coulisse articulated upthrust-fold zones and en-echelonly overthrust covers. The geodynamic setting of the grouping of the compression axes in the western part of the Donbass, which was experiencing orogenic uplift, caused the thrust of allochthonous geomasses to the syneclise related autochthon of the southeastern segment of the depression. In the West Donets Graben, this caused an increase in the section beyond the Hercynian Neoautochthon and the Cimmerian-Alpine allochthon with the formation of a clinoform wedging Segment. Along the main strike-slip faults, which form the tectonic rails of its invasion, geodynamic zones of geomass squeezing out, formed by curvilinear, en-echelonly upthrow folds, were formed. In the foreland of the Segment, at the ends of dynamically coupled thrust and strike-slip faults, a forward compression fan is formed; in the hinterland, on the roots of thrust covers, folded suture zones are formed. Based on the results of the kinematic analysis of the Hercynian and Alpine deformation structures, a new kinematic model of the tectonic inversion of the riftogenic structure of the Southeastern Segment of the Dnieper-Donets Basin has been developed. In accordance with it, the deformations of the sedimentary cover of the West Donets Graben were carried out according to the kinematic mechanism of a transverse orocline of pushing geomasses of the sub-thrust type, under the pressure of the tectonic stamp of the Donets Foldbelt.

scholarly journals GEODYNAMICS

GEODYNAMICS ◽  
2021 ◽  
Vol 1(30)2021 (1(30)) ◽  
pp. 25-35
Author(s):  
Оleksii Bartaschuk ◽  
◽  
Vasyl Suyarko ◽  
Keyword(s):  
Regional Scale ◽  
Kinematic Model ◽  
Original Method ◽  
Strike Slip ◽  
The Body ◽  
Practical Significance ◽  
Donets Basin ◽  
Transverse Displacement ◽  
North West ◽  
Tectonic Inversion

The second part of the article studies the tectonic conditions and natural mechanisms of tectonic inversion of the Dnieper-Donets Basin and the Western Donets Graben. Method. The research uses the original method of reconstruction of fields of tectonic stresses and deformations. It also makes tectonophysical analysis of geostructures was used. The analytical base of the research consisted of the latest materials of geo-mapping, numerical modeling of deformations of the southern edge of the Eastern European platform and comparison of model and reconstructed stress fields. Results. In the geodynamic environment of the interference of the intraplate submeridional collision compression with the regional strike-slip stress field, the inversion deformations of the rift-like geostructure took place in the uplift-thrust and strike-slip modes. This led to significant horizontal movements of geomass of sedimentary rocks, deformation folding with the formation of three inversion floors - Late Hercynian (Saal-Pfalz), Early Alpine (Laramian) and Late Alpine (Attic). They formed structural ensembles of scaly tectonic covers of transverse displacement of geomass a from axial to onboard zones, folded covers of longitudinal approach from the Donbas Foldbelt and long linear anti- and synforms, the axes of which are oriented orthogonally to the direction of geomass advancement. Together they form the body of the Segment of Tectonic Wedging of geomass, which is distinguished as part of the Cover-Folded System of Tectonic Thrusting of regional scale. A feature of the tectonic framework of the Segment is the curvature of the planes of the main thrusts, which limit it, and smaller plumage thrusts, which control the folded covers of the thrust. It is associated with a change in the extension of the thrusts from the north-west in the territory of the Western Donets Graben to the western direction in the extreme south-east of the Basin. This causes the corresponding bending of the axes of the fracture anti- and synforms. Structural patterns of folding with a tendency to adapt the axes of folds to the extension of thrusts indicate significant horizontal displacements of geomas of the sedimentary stratum, which in conditions of limited geological space cause secondary deformations of linear folded forms. Due to the displacement of geomas from the zones of maximum compression in the axial part of the Graben to the zones of geodynamic shadow - in the direction of the Oryl depression and Graben boards, the West Donets Cover-Folded Tectonic Region was formed within the transition zone. Scientific novelty. The study completed an original kinematic model of tectonic inversion of the Western Donets Graben was completed. The mechanism of inversion, due to which the riftogenic structure is completely destroyed by folded deformations of platform orogeneses, is caused by the pressure of the "tectonic stamp" of the Donbas Foldbelt. Under its influence, a segment of tectonic wedge was formed in the Graben, which was diagnosed with oroclin of transverse extension of the sliding type. The body of the Oroclin is formed by echeloned, rock-articulated ensembles of anticlinal uplift -folds, synclines and scaly plates-covers of pushing. A geodynamic injection band was formed in the foreland of the Tectonic Orocline extension, where folded zones of geomas displacement were formed, which consist of coulisse articulated uplift-anticlines. At the top of the Orocline, at the ends of dynamically conjugate main thrusts, an advanced tectonic compression fan is formed. In the rear of the Oroclin – hinterland are tectonic sutures – the roots of the folding covers of the approach. Practical significance. Development of a structural-kinematic model of tectonic inversion of the Western Donets Graben will allow to improve the geodynamic model of tectonic inversion of the Dnieper-Donets paleorift, on the basis of which regional schemes of tectonic and oil-gas-geological zoning will be adjusted.

scholarly journals Tectono-Sedimentary Evolution of the Cenozoic Basins in the Eastern External Betic Zone (SE Spain)

Geosciences ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 394
Author(s):  
Manuel Martín-Martín ◽  
Francesco Guerrera ◽  
Mario Tramontana
Keyword(s):  
Strike Slip ◽  
Alluvial Fan ◽  
Tectonic Activity ◽  
Time Interval ◽  
Se Spain ◽  
The Third ◽  
Sedimentary Evolution ◽  
Marine Sedimentation ◽  
Geodynamic Processes ◽  
Early Paleocene

Four main unconformities (1–4) were recognized in the sedimentary record of the Cenozoic basins of the eastern External Betic Zone (SE, Spain). They are located at different stratigraphic levels, as follows: (1) Cretaceous-Paleogene boundary, even if this unconformity was also recorded at the early Paleocene (Murcia sector) and early Eocene (Alicante sector), (2) Eocene-Oligocene boundary, quite synchronous, in the whole considered area, (3) early Burdigalian, quite synchronous (recognized in the Murcia sector) and (4) Middle Tortonian (recognized in Murcia and Alicante sectors). These unconformities correspond to stratigraphic gaps of different temporal extensions and with different controls (tectonic or eustatic), which allowed recognizing minor sedimentary cycles in the Paleocene–Miocene time span. The Cenozoic marine sedimentation started over the oldest unconformity (i.e., the principal one), above the Mesozoic marine deposits. Paleocene-Eocene sedimentation shows numerous tectofacies (such as: turbidites, slumps, olistostromes, mega-olistostromes and pillow-beds) interpreted as related to an early, blind and deep-seated tectonic activity, acting in the more internal subdomains of the External Betic Zone as a result of the geodynamic processes related to the evolution of the westernmost branch of the Tethys. The second unconformity resulted from an Oligocene to Aquitanian sedimentary evolution in the Murcia Sector from marine realms to continental environments. This last time interval is characterized as the previous one by a gentle tectonic activity. On the other hand, the Miocene sedimentation was totally controlled by the development of superficial thrusts and/or strike-slip faults zones, both related to the regional geodynamic evolutionary framework linked to the Mediterranean opening. These strike-slip faults zones created subsidence areas (pull-apart basin-type) and affected the sedimentation lying above the third unconformity. By contrast, the subsidence areas were bounded by structural highs affected by thrusts and folds. After the third unconformity, the Burdigalian-Serravallian sedimentation occurred mainly in shallow- to deep-water marine environments (Tap Fm). During the Late Miocene, after the fourth unconformity, the activation of the strike-slip faults zones caused a shallow marine environment sedimentation in the Murcia sector and a continental (lacustrine and fluvial) deposition in the Alicante sector represented the latter, resulting in alluvial fan deposits. Furthermore, the location of these fans changed over time according to the activation of faults responsible for the tectonic rising of Triassic salt deposits, which fed the fan themselves.

scholarly journals U–Pb dating of middle Eocene–Pliocene multiple tectonic pulses in the Alpine foreland

Solid Earth ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 2539-2551
Author(s):  
Luca Smeraglia ◽  
Nathan Looser ◽  
Olivier Fabbri ◽  
Flavien Choulet ◽  
Marcel Guillong ◽  
...  
Keyword(s):  
Middle Eocene ◽  
Regional Scale ◽  
Earthquake Hazard ◽  
Late Eocene ◽  
Passive Margin ◽  
Tectonic Activity ◽  
Thrust Belt ◽  
Fold And Thrust Belt ◽  
Earthquake Hazard Assessment ◽  
Alpine Foreland

Abstract. Foreland fold-and-thrust belts (FTBs) record long-lived tectono-sedimentary activity, from passive margin sedimentation, flexuring, and further evolution into wedge accretion ahead of an advancing orogen. Therefore, dating fault activity is fundamental for plate movement reconstruction, resource exploration, and earthquake hazard assessment. Here, we report U–Pb ages of syn-tectonic calcite mineralizations from four thrusts and three tear faults sampled at the regional scale across the Jura fold-and-thrust belt in the northwestern Alpine foreland (eastern France). Three regional tectonic phases are recognized in the middle Eocene–Pliocene interval: (1) pre-orogenic faulting at 48.4±1.5 and 44.7±2.6 Ma associated with the far-field effect of the Alpine or Pyrenean compression, (2) syn-orogenic thrusting at 11.4±1.1, 10.6±0.5, 9.7±1.4, 9.6±0.3, and 7.5±1.1 Ma associated with the formation of the Jura fold-and-thrust belt with possible in-sequence thrust propagation, and (3) syn-orogenic tear faulting at 10.5±0.4, 9.1±6.5, 5.7±4.7, and at 4.8±1.7 Ma including the reactivation of a pre-orogenic fault at 3.9±2.9 Ma. Previously unknown faulting events at 48.4±1.5 and 44.7±2.6 Ma predate the reported late Eocene age for tectonic activity onset in the Alpine foreland by ∼10 Myr. In addition, we date the previously inferred reactivation of pre-orogenic strike-slip faults as tear faults during Jura imbrication. The U–Pb ages document a minimal time frame for the evolution of the Jura FTB wedge by possible in-sequence thrust imbrication above the low-friction basal decollement consisting of evaporites.

scholarly journals Age and paleoenvironment of the Nukhul Formation, Gulf of Suez, Egypt: Insights from palynology, palynofacies and organic geochemistry

GeoArabia ◽  
2013 ◽  
Vol 18 (4) ◽  
pp. 137-174
Author(s):  
Haytham El Atfy ◽  
Rainer Brocke ◽  
Dieter Uhl
Keyword(s):  
Nile Delta ◽  
Organic Geochemistry ◽  
Regional Scale ◽  
Tectonic Activity ◽  
Gulf Of Suez ◽  
Spores And Pollen ◽  
Shallow Marine ◽  
History Of ◽  
Geochemical Analyses ◽  
Rock Eval

ABSTRACT Palynological results of a detailed study carried out on 56 samples retrieved from two selected wells (GH 404-2A and SA-E6A) of the Hilal and Shoab Ali fields within the southern part of the Gulf of Suez, Egypt, are presented. This study is mainly focused on the poorly dated Nukhul Formation, for which very little information from palynology is available despite its importance from a petroleum viewpoint. The assemblages discovered in our study are moderately preserved and reveal a sparse but significant record of spores and pollen and dinoflagellates together with highly diverse fungi and algal taxa, e.g. Botryococcus and Pediastrum. A latest Oligocene–Early Miocene (Chattian–Aquitanian) age has been suggested for the Nukhul Formation, based on compiling palynostratigraphic and ecologic data obtained from palynomorphs that have previously been assumed to be representatives for this period on a regional scale. In addition, the Oligocene/Miocene Boundary (OMB) could be lithostratigraphically defined within the studied formation, most likely at the boundary between the lower Shoab Ali Member and upper Ghara Member. A fungal/algal ‘event’ within the interval from 11,370–11,430 ft in the GH 404-2A Well may be associated with a strong regressive phase. Such a regression was previously observed in the Nile Delta and other locations around the Red Sea province, and may be assigned to the global Mi-1 glaciation event at the OMB. However, not only glacial-driven eustacy but also tectonic activity related to the Gulf of Suez rifting may have contributed in forming such an event. Palynofacies investigations were carried out under both transmitted and fluorescence microscopy and the results were partly supplemented by existing organic geochemical analyses (GH 404-2A Well) involving Rock-Eval pyrolysis and total organic carbon (TOC) measurements. The analysis was used to interpret the depositional regime, paleoenvironment and thermal maturation history of the studied succession. These results support the temporary existence of shallow, pond- or lake-like aquatic habitats during deposition of the lower Shoab Ali Member that evolved into a shallow-marine environment with the onset of the deposition of upper Ghara Member of the Nukhul Formation.

Chapter 8 Outboard-migrating accretionary orogeny at 1.9–1.8 Ga (Svecokarelian) along a margin to the continent Fennoscandia

2020 ◽  
Vol 50 (1) ◽  
pp. 237-250 ◽  
Author(s):  
Michael B. Stephens
Keyword(s):  
Base Metal ◽  
Regional Scale ◽  
Volcanic Rocks ◽  
Shear Zones ◽  
Strike Slip ◽  
Base Metal Sulphide ◽  
Metal Sulphide ◽  
Time Period ◽  
Ductile Shear Zones ◽  
Strike Slip Movement

AbstractAn intimate lithostratigraphic and lithodemic connection between syn-orogenic rock masses inside the different lithotectonic units of the 2.0–1.8 Ga (Svecokarelian) orogen, Sweden, is proposed. A repetitive cyclic tectonic evolution occurred during the time period c. 1.91–1.75 Ga, each cycle lasting about 50–55 million years. Volcanic rocks (c. 1.91–1.88 Ga) belonging to the earliest cycle are host to most of the base metal sulphide and Fe oxide deposits inside the orogen. Preservation of relict trails of continental magmatic arcs and intra-arc basins is inferred, with differences in the depth of basin deposition controlling, for example, contrasting types of base metal sulphide deposits along different trails. The segmented geometry of these continental magmatic arcs and intra-arc basins is related to strike-slip movement along ductile shear zones during transpressive events around and after 1.88 Ga; late orogenic folding also disturbed their orientation on a regional scale. A linear northwesterly orogenic trend is suggested prior to this structural overprint, the strike-slip movement being mainly parallel to the orogen. A solely accretionary orogenic model along an active margin to the continent Fennoscandia, without any trace of a terminal continent–continent collision, is preferred. Alternating retreating and advancing subduction modes that migrated progressively outboard and southwestwards in time account for the tectonic cycles.

scholarly journals Analysis and Classification of Natural and Human-Induced Ground Deformations at Regional Scale (Campania, Italy) Detected by Satellite Synthetic-Aperture Radar Interferometry Archive Datasets

2019 ◽  
Vol 11 (23) ◽  
pp. 2822 ◽  
Author(s):  
Fabio Matano
Keyword(s):  
Urban Areas ◽  
Ground Deformation ◽  
Regional Scale ◽  
Tectonic Activity ◽  
Persistent Scatterer Interferometry ◽  
Campania Region ◽  
Ground Deformations ◽  
Persistent Scatterer ◽  
Geological Conditions

The high levels of geo-hydrological, seismic, and volcanic hazards in the Campania region prompted full data collection from C-band satellites ERS-1/2, ENVISAT, and RADARSAT within regional (TELLUS) and national (PST-A) projects. The quantitative analysis, interpretation, and classification of natural and human-induced slow-rate ground deformations across a span of two decades (1992–2010) was performed at regional scale (Campania, Italy) by using interferometric archive datasets, based on the Persistent Scatterer Interferometry approach. As radar satellite sensors have a side-looking view, the post-processing of the interferometric datasets allows for the evaluation of two spatial components (vertical and E-W horizontal ones) of ground deformation, while the N-S horizontal component cannot be detected. The ground deformation components have been analyzed across 89.5% of the Campania territory within a variety of environmental, topographical, and geological conditions. The main part (57%) of the regional territory was characterized during 1992–2010 by stable areas, where SAR signals do not have recorded significant horizontal and vertical components of ground deformation with an average annual rate greater than +1 mm/yr or lower than −1 mm/yr. Within the deforming areas, the coastal plains are characterized by widespread and continuous strong subsidence signals due to sediment compaction locally enhanced by human activity, while the inner plain sectors show mainly scattered spots with locally high subsidence in correspondence of urban areas, sinkholes, and groundwater withdrawals. The volcanic sectors show interplaying horizontal and vertical trends due to volcano-tectonic processes, while in the hilly and mountain inner sectors the ground deformation is mainly controlled by large-scale tectonic activity and by local landslide activity. The groundwater-related deformation is the dominant cause of human-caused ground deformation. The results confirm the importance of using Persistent Scatterer Interferometry data for a comprehensive understanding of rates and patterns of recent ground deformation at regional scale also within tectonically active areas as in Campania region.

Regional scale prospectivity modelling of NW India for REE deposits associated with carbonatites and alkaline complexes

2020 ◽  
Author(s):  
Malcolm Aranha ◽  
Alok Porwal ◽  
Manikandan Sundaralingam ◽  
Amber Markan ◽  
Ignacio González-Álvarez ◽  
...  
Keyword(s):  
Industrial Development ◽  
Systems Approach ◽  
Fuzzy Inference ◽  
Genetic Model ◽  
Regional Scale ◽  
Geodynamic Setting ◽  
Inference System ◽  
Primary Deposit ◽  
Alkaline Complexes

<p>The rare earth elements (REEs) are a group of seventeen metals including 15 lanthanides, scandium and yttrium.  These metals have been projected to be critical for future industrial development. However, India currently does not have any economic grade primary deposit of REEs; all of India’s production comes from monazite-bearing beach sands along the eastern and western coasts that have been derived from REEs-enriched continental rocks such as pegmatites or carbonatites. This contribution documents a GIS-based prospectivity model for exploration targeting of REE associated with carbonatites and alkaline-complexes in the geologically permissive tracts of NW India comprising parts of western Rajasthan and northern Gujarat. A mineral systems approach is applied to model the key ingredients of an REE system including geodynamic setting; fertile mantle/crustal sources of REEs; deep to shallow crustal architecture; and REE deposition.  This conceptual genetic model of REE mineral systems is, in turn, used to identify the key regional-scale REE-deposit targeting criteria in NW India. Regional-scale multi-parametric exploration datasets are processed to represent the targeting criteria in form of predictor GIS layers. Finally, an expert-driven fuzzy inference system is designed for delineating and raking prospective REE targets. Simultaneously, the stochastic and systemic uncertainties in the prospectivity modeling are modelled to delineated (a) high priority REE exploration targets areas with low uncertainty and high prospectivity for immediate ground follow up and (b) areas with high uncertainty and high prospectivity for further data acquisition in order to reduce uncertainty.</p>

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