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Summary Mechanical impact stress on the vocal fold surface, particularly when excessive, has been postulated to cause the so-called phonotraumatic tissue lesions, such as nodules and polyps. The collision stress between the vocal folds depends on the vocal fold velocity at the time of impact. Hence this vocal fold collision speed is a relevant parameter when considering biomechanical economy of phonation, especially in voice professionals needing a louder voice than normal. Combining a precise photometric measurement of glottal area and simultaneous measurements of translaryngeal impedance (electroglottogram) for identifying the time of the maximum rate of increase of vocal fold contact allows computing the vocal fold collision speed in a wide range of loudnesses. The vocal fold collision speed is - for modal voicing - always smaller than the maximum vocal fold velocity during the closing phase, but it strongly increases with intensity. Moreover, this increase shows a biphasic pattern, with a significant enhancement from a certain value of dB on. Understanding physiological variables that influence vocal fold collision forces provides relevant insight into the pathophysiology and the prevention of voice disorders associated with phonotraumatic vocal hyperfunction.

Simultaneous heatwaves affecting multiple regions (referred to as concurrent heatwaves) pose compounding threats to various natural and societal systems, including global food chains, emergency response systems, and reinsurance industries. While anthropogenic climate change is increasing heatwave risks across most regions, the interactions between warming and circulation changes that yield concurrent heatwaves remain understudied. Here, we quantify historical (1979–2019) trends in concurrent heatwaves during the warm season [May–September (MJJAS)] across the Northern Hemisphere mid- to high latitudes. We find a significant increase of ∼46% in the mean spatial extent of concurrent heatwaves and ∼17% increase in their maximum intensity, and an approximately sixfold increase in their frequency. Using self-organizing maps, we identify large-scale circulation patterns (300 hPa) associated with specific concurrent heatwave configurations across Northern Hemisphere regions. We show that observed changes in the frequency of specific circulation patterns preferentially increase the risk of concurrent heatwaves across particular regions. Patterns linking concurrent heatwaves across eastern North America, eastern and northern Europe, parts of Asia, and the Barents and Kara Seas show the largest increases in frequency (∼5.9 additional days per decade). We also quantify the relative contributions of circulation pattern changes and warming to overall observed concurrent heatwave day frequency trends. While warming has a predominant and positive influence on increasing concurrent heatwave frequency, circulation pattern changes have a varying influence and account for up to 0.8 additional concurrent heatwave days per decade. Identifying regions with an elevated risk of concurrent heatwaves and understanding their drivers is indispensable for evaluating projected climate risks on interconnected societal systems and fostering regional preparedness in a changing climate.Significance StatementHeatwaves pose a major threat to human health, ecosystems, and human systems. Simultaneous heatwaves affecting multiple regions can exacerbate such threats. For example, multiple food-producing regions simultaneously undergoing heat-related crop damage could drive global food shortages. We assess recent changes in the occurrence of simultaneous large heatwaves. Such simultaneous heatwaves are 7 times more likely now than 40 years ago. They are also hotter and affect a larger area. Their increasing occurrence is mainly driven by warming baseline temperatures due to global heating, but changes in weather patterns contribute to disproportionate increases over parts of Europe, the eastern United States, and Asia. Better understanding the drivers of weather pattern changes is therefore important for understanding future concurrent heatwave characteristics and their impacts.

The study proposes to map the tectonic accidents existing in Bafoussam locality using the remote sensing and vertical electrical sounding methods. The principal component analysis and directional filtering applied respectively to Landsat8 and SRTM images allowed to extract remote sensing lineament map. The interpretative rose diagram shows a distribution of lineaments following four directions: NE-SW, NW-SE, N-S and E-W. The main directions are from N30°E to N80°E; these are those of large strike-slip of the Central Pan-African Fold Belt (CAFB) in Cameroon and from the extension of the Central Cameroonian Shear Zone (CCSZ) in the studied area. The superimposition of these lineaments on the hydrographic network map enabled establishing genetic links because rivers flow following the main N30°E and the secondary N120°E lineament directions. The superimposition of the iso-resistivity maps resulting allowed to extract the geophysical lineament map which has been confirmed by achieving resistivity sections in depth. These lineaments are N40°E to N60°E directed comparable to the network fracture and foliation direction on orthogneiss flagstones within the area. These lineaments superimposed on those automatically extracted by remote sensing show a good correlation following the two methods used. The both mapping methods therefore allowed to extract the fracturing map zone. As groundwater is generally stored in the fracture network of hard rocks, the results of this study will thus provide progress in the course of wells and boreholes implantation. The second generation of fractures with a N140°E striking direction is the most appropriate for the hydrogeological studies in Bafoussam.

Sigmoidal fold and fault geometries are typical kinematic indicators of strike-slip fault zones. We document kilometer-scale, normal faults with sigmoidal plan-view geometries within the dextral pull-apart Bahia Basin, at the rear of the obliquely convergent South Caribbean Deformed Belt, offshore Colombia. Using 3D seismic reflection data calibrated to wells, closely spaced, low-displacement, planar normal faults are mapped within the Miocene strata. A series of seismic horizontal (time) slices and computed seismic attributes are used to interpret the 3D configuration of these faults. The closely spaced faults display an east–west trend with a progressive rotation into a northwest–southeast trend. In map view, the fault traces curve toward their tips, describing a sigmoidal-Z geometry that terminates at discrete northeast–southwest-trending fault zones. The structures observed may correspond to either tension fractures, which form theoretically at 45°, or antithetic shear fractures with normal displacement formed at 50°–70° to the boundaries of a dextral shear zone. These scenarios lead to a clockwise block rotation of between 20° and 40° within the shear zone. This study shows the first example of vertical-axis block rotations observed offshore in the western end of the South Caribbean margin and is an important example of the use of 3D seismic data to identify rotations where paleomagnetic studies are not available.

This study defines a new bivalve species, Naiadites devonicus nov. sp., of Famennian (Late Devonian) age. The material was excavated from the non-marine deposits of the Waterloo Farm Lagerstatte in South Africa, which form part of the Witpoort Formation (Witteberg Group, Cape Supergroup) of the Cape Fold Belt region. The type material of Naiadites devonicus nov. sp. is preserved in metamorphosed, clayey to silty mudstones of a coastal estuarine to lagoonal facies, deposited along the shoreline of the Agulhas Sea, in a high-palaeolatitude Gondwanan setting. The new bivalve species is the stratigraphically oldest representative of the genus Naiadites Dawson. It is a faunal element of a high-latitude palaeoecosystem, immediately preceding the Hangenberg extinction event at the end of the Late Devonian.

Accurate interpretation of clutter seismic reflection is of great significance to make clear the structural geometry and kinematics characteristics. Based on field investigations, boreholes and seismic data, forward modeling is carried out under the trishear model of fault-propagated fold principle, and the activity characteristics of the main faults in the study area are quantitatively analyzed using the balanced restoration technique, which may provide important indication for the potential petroleum exploration and development. The results show that separated by Tuziluoke and Tugerming fault, the structural style of the study area can be divided into the deeply buried forelimb, the kink band and the tiny anticline backlimb section. The Tuziluoke fault has been active with strong intensity since the sedimentary period of the Kuqa Formation and, which controls the formation of the growth strata in the deep buried forelimb of the Tuziluoke anticline. The Tugerming fault has been active intermittently since the end of the Jurassic, causing the strata denudation of the Late Jurassic to Paleogene in varying degrees and the development of series of regulating faults. The multi-stage tectonic activities caused the structural high of the anticline migrated from east to west.

Submarine landslides can be triggered by several processes and involve a variety of mechanisms. These phenomena are important sediment transport processes, but they also constitute a significant geohazard. Mapping of the southwestern Caribbean Sea using 3D seismic data has allowed identification of several submarine landslides in the Colombian Margin in the area dominated by the Southern Sinú Fold Belt (SSFB). A poststack depth-migrated seismic cube survey with a 12.5 by 12.5 m bin spacing was used to identify landslides in an area covering 5746 km2. Landslides were interpreted using a seafloor morphologic parameter identification process and the internal deformation of the slope-forming material, as seen from seismic data. A total of 93 landslides were identified and classified based on their movement styles as follows: 52 rotational, 29 translational, and 12 complex landslides. In addition, 12 distinct deformational zones and a zone of mass transport complex (MTC) were identified. Five different ground condition terrains were interpreted based on landslide type and distribution as well as in geologic structures and seismic reflection analysis. Two main processes seem to influence landslides in the study area. First is the folding and faulting involved in the SSFB evolution. This process results in oversteepened slopes that start as deformational zones and then fail as translational or rotational slides. Those individual landslides progressively become complex landslide zones that follow geologic structural orientation. Second is the continental shelf break erosion by debris flows, which fills in intraslope subbasins and continental rise with several MTCs. According to the results, risk of damage by landslides increases in distances shorter than 4 km along structural ridge foothills in the study zone.

We demonstrate how lithological and mechanical stratification of Ediacaran–Carboniferous sedimentary package governs strain partitioning in the Lublin Basin (LB) which was incorporated in the marginal portion of the Variscan fold-and-thrust belt. Based on the geometry of seismic reflectors, the pre-Permian–Mesozoic sedimentary sequence was subdivided into two structural complexes differing in structural style. The lower one reveals forelandward-vergent imbrication, while the upper one comprises fold train, second-order deformations, and multiple local detachments. Lithological composition of the upper structural complex controlled geometry, kinematics, and position of compressional deformations in stratigraphic profile. System of foreland-vergent thrusts which links lower and upper detachment developed due to efficiency of simple shear operating in heterogeneous clastic-carbonate-evaporitic strata of the Lower–Upper Devonian age. Internal homogeneity promoted the formation of conjugate sets of thrusts in Silurian shales and Upper Devonian limestones. Structural seismic interpretation combined with sequential restoration revealed localised thickening of Devonian strata and up to 5% difference in length of Devonian horizons. This mismatch is interpreted as a manifestation of distributed shortening, including layer-parallel shortening (LPS), which operated before or synchronously to the initiation of folding. The amount of distributed strain is comparable with numbers obtained in external parts of other fold-and-thrust belts. The outcomes derived from this study may act as a benchmark for studying variability in a structural style of multilayered sequences which were incorporated in the external portion of other fold-and-thrust belts.

The mapping and characterization of thin gas sand layers have always been a challenge through conventional seismic interpretation procedures. Seismic inversion techniques have been effectively applied to evaluate the hydrocarbon reservoirs with high heterogeneity and deep burial depth with thicknesses below seismic resolution. In this study, thin gas sand layers of the Lower Ranikot Formation of the Mehar gas field in the Kirthar Fold Belt, Pakistan, have been characterized via the application of sensitive post-stack model-based seismic inversion (PMBSI) and pre-stack simultaneous seismic inversion (PSSI). These sands are producing in the nearby fields; however, their potential is still untapped in the study area, which needs to be explored for further development. In order to evaluate the gas potential, petrophysical analysis demarcated three gas-bearing zones within the targeted reservoir. The spatial extent of these identified sand packages has been evaluated in detail by the application of the above selected seismic inversion techniques. The results of PMBSI depicted low impedance values within the sand layers of the Lower Ranikot Formation, but PSSI efficaciously separated the thin gas-bearing and non-bearing sand intervals. Furthermore, the impedance-derived porosities predicted via probabilistic neural network (PNN) show excellent agreement with the computed porosities from interpreted well logs and at producing blind wells. The techniques adopted to delineate and map the potential thin gas sands of the Mehar gas field may be very fruitful and adequate for basins with similar geological settings.

Shear wave birefringence is a robust tool to infer the direction and strength of deformation in the lithosphere and sub-lithospheric mantle. Situated at the north-eastern flank of the Indian subcontinent, the Shillong plateau shows evidence of pop-up dynamics. It is bounded by major geologic structures from all the four corners. The present study presents new results from shear wave splitting using SKS, SKKS and PKS phases. A total of 749 waveforms were analysed to produce 129 high-quality splitting measurements. The delay time makes a distinctive variation in different parts of the plateau ranging from 0.4 to 2.4 s, while the trend of fast polarization direction (FPD) ranges from NE–SW to E–W along a north-south traverse. Shear at the base of the lithosphere due to absolute plate motion (APM) related strain of Indian plate explains the NE–SW (45 $$^\circ$$ ) directed deformation beneath the northern and central Shillong plateau. Situated away from the Indo-Eurasian collisional tectonics, the present deformation behaviour at the northern and central Shillong plateau mass are parallel to the APM of the Indian plate in a no net rotation reference frame, ruling out the possibility of compressional tectonics and major geological features in influencing the anisotropic pattern in this particular region. Contrary to other parts, the southern proximity of Shillong plateau displays a complex anisotropic behaviour and deformation parallel to the extension of Dauki fault. The transpressional tectonics along with coherent lithospheric deformation are supposed to be more active for an E–W aligned anisotropic behavior, though a possible attribution due to overthrusting and eastward lateral motion of the Indo-Burma fold belt may not be avoided.

The West Junggar (WJ) is generally accepted as a Paleozoic archipelago-type orogenic system and records a multiple arcs amalgamation history; however, some of the associated processes require further examination. In this paper, we conducted detailed field investigations and large-scale mapping in the Saier Mountains, northern WJ, and identified several episodes of magmatism and deformation events. The felsic rocks (dioritic porphyrite and granitic porphyry), characterized by a dense cleavage, were emplaced at the Early–Middle Silurian (433–423 Ma). These rocks exhibit geochemical characteristics comparable to those of the coeval adakite-like rocks and A2-type granites in the Xiemisitai Mountains. The undeformed mafic dike swarms yielded SHRIMP zircon age of 382 ± 6 Ma and intruded the Hebukesaier ophiolitic melange (HOM) as well as the surrounding rocks. The HOM, Silurian felsic intrusions and pyroclastic rocks (422 ± 9 Ma) in the Saier Mountains commonly display cleavage attributed north–south shortening during 422–382 Ma. Deep-sea bedded cherts and turbidites in the area also experienced deformation and exhibited cleavage, with subduction-related fold deformation partially preserved in the HOM. The fold deformation was greatly related to a subduction-accretion process of the Hongguleleng–Balkybey Ocean during the Ordovician. Considering the geochronology and geochemistry data, the extensive Silurian–Early Devonian magmatism in the northern WJ indicates a prolonged (~40 Ma) and episodic post-collisional extension in this orogen and records an obvious trend of crustal temperature increasing and thickness thinning from 435 to 410 Ma. The regional extrusion deformation was attributed to the southward subduction of the Irtysh–Zaysan Ocean during the Middle Devonian, and then the slab roll-back offered an extensional setting which favored the emplacement of mantle-derived mafic dike swarms. We propose that the northern WJ probably experienced a complicated evolution involving archipelago amalgamation and tectonic transform in the middle Paleozoic, providing a new sight to reveal the orogenic process of the Central Asian Orogenic Belt (CAOB).

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.

In this study, the sandstones of the Bahariya Formation in the Abu Gharadig Field, which is a promising oil reservoir in the Abu Gharadig Basin, Western Desert, Egypt, were assessed. The wireline logs from three wells (Abu Gharadig-2, Abu Gharadig-6, and Abu Gharadig-15) were studied using seismic and petrophysical analyses. Based on seismic data, the study area contains an ENE–WSW anticlinal structure, which is divided by a set of NW–SE normal faults, reflecting the effect of Late Cretaceous dextral wrench tectonics on the northern Western Desert. The visual analysis of the well logs reveals a potential zone within well Abu Gharadig-2 located between depths of 10,551 and 10,568 ft (zone A). In contrast, potential zones were detected between depths of 11,593–11,623 ft (zone B) and 11,652–11,673 ft (zone C) in well Abu Gharadig-6. In well Abu Gharadig-15, potential zones are located between depths of 11,244–11251ft (zone D) and 11,459–11,467 ft (zone E). The quantitative evaluation shows that the intervals B and C in well AG-6 are the zones with the highest oil-bearing potential in the Abu Gharadig Field in terms of the reservoir quality. They exhibit the lowest shale volume (0.06–0.09), highest effective porosity (0.13), minimum water saturation (0.11–0.16), lowest bulk volume of water (0.01–0.02), high absolute permeability (10.92–13.93 mD), high relative oil permeability (~ 1.0), and low water cut (~ 0). The apex of the mapped fold represents that the topmost Bahariya Formation in the Abu Gharadig Field for which the drilling of additional wells close to well AG-6 is highly recommended.

Pre-rift salt controls structural style variability within rifts by decoupling sub- and supra-salt faults. However, the way in which this variability controls sediment erosion and dispersal, and facies distributions within the coeval syn-rift stratigraphic succession, remains poorly known. We here use 3D seismic reflection and borehole data to study the tectono-stratigraphic development of the Halten Terrace, offshore Mid-Norway, a salt-influenced rifted margin formed during Middle to Late Jurassic extension. On the eastern basin margin the rift structural style passes southwards from an unbreached extensional growth fold dissected by numerous horst and graben (Bremstein Fault Complex), into a single, through-going normal fault (Vingleia Fault Complex). This southwards change in structural style is likely related to the pinch-out of or a change in the dominant lithology (and thus rheology) within a pre-rift (Triassic) evaporite layer, which was thick and/or mobile enough in the north to decouple basement- and cover-involved faulting, and to permit extensional forced folding. As a result, the salt-influenced Bremstein Fault Complex underwent limited footwall uplift, with minor erosion of relatively small horsts supplying only limited volumes of sediment to the main downdip depocentre. In contrast, the Vingleia Fault Complex, which was directly coupled to basement, experienced significant uplift and extensive footwall erosion. The footwall of this structure also locally underwent salt-detached gravity gliding and collapse as the pre-rift detachment was tilted. Our results show that where through-going normal faults develop along the rift flanks, the presence of a pre-rift salt layer will suppress the topographic expression of the footwall. The pre-rift salt layer may however facilitate footwall collapse and limit the volume of sediment supplied to downdip basins. Our results also show that variable topography along the rift flanks facilitated the development of relatively small, localised, intra-rift flank accommodation that trapped flank-derived sediment, and which meant basins nearer the rift axis were starved of sediment.

The formation conditions of the Paleogene–Neogene metalliferous coals have been studied under conditions of activated tectonic movements in the junction zone of the Turan Block and Zeya–Bureya Basin. A keyboard structure of the block hosting the Selemdzha–Tom and Arkhara grabens, which are divided by the Bureya Horst limited by a systems of NE-trending strike-slip faults, has been established. It is shown that the most favorable conditions for the accumulation of ore trace elements in coals were provided by submerged areas of the block due to erosion of the Late Cretaceous ore-bearing chemical weathering mantles. Trace elements migrated via a paleohydronetwork, which drained the grabens and adjacent sedimentation troughs of the eastern margin of the Zeya–Bureya Basin. The ore material was transported to the areas of coal accumulation mostly in the dissolved and clastic forms, which is evident from the similar elemental composition of coals of the Zeya–Bureya Basin and geochemical anomalies of the Turan Block.

Glycosyltransferases (GTs) play fundamental roles in nearly all cellular processes through the biosynthesis of complex carbohydrates and glycosylation of diverse protein and small molecule substrates. The extensive structural and functional diversification of GTs presents a major challenge in mapping the relationships connecting sequence, structure, fold and function using traditional bioinformatics approaches. Here, we present a convolutional neural network with attention (CNN-attention) based deep learning model that leverages simple secondary structure representations generated from primary sequences to provide GT fold prediction with high accuracy. The model learns distinguishing secondary structure features free of primary sequence alignment constraints and is highly interpretable. It delineates sequence and structural features characteristic of individual fold types, while classifying them into distinct clusters that group evolutionarily divergent families based on shared secondary structural features. We further extend our model to classify GT families of unknown folds and variants of known folds. By identifying families that are likely to adopt novel folds such as GT91, GT96 and GT97, our studies expand the GT fold landscape and prioritize targets for future structural studies., Glycosyltransferases (GT) are proteins that display extensive sequence and functional variation on a subset of 3D folds. Here, the authors use interpretable deep learning to predict 3D folds from sequence without the need for sequence alignment, which also enables the prediction of GTs with new folds.

The I-type Pan-African Misajé granites, situated in the Western domain of the Central African Fold Belt are among the late-to post tectonic granites that intruded the ante-Pan-African country rocks. In this study, magnetic susceptibility and geochemistry data are integrated to evaluate the productive and non-productive metal potential of these I-type plutonic granites, which comprise Leucocratic granite, Biotite granite, Biotite-hornblende granite, and granodiorites. The magnetic susceptibility of the representative rock samples of the Misajé pluton ranges from 0.001 × 10−3 SI to 33.2 × 10−3 SI. These values indicate the coexistence of both magnetite and ilmenite-series. The magnetite-series (>3 × 10−3 SI; oxidized type) constitute about 32 vol.% while the ilmenite-series ( 1) grains sizes. The Misajé plutonics are high potentially productive in Zn, Th, ilmenite, and magnetite and low productive in Sn, W and Cu though their extension remains limited, probably due to the remobilization of the ancient Paleoproterozoic crust that would have contributed to the dispersing of pre-Pan-African metal deposits.

A new genus, Tonomochota n. gen., and three new species, T. khasanensis n. sp., T. sikhotana n. sp., and T. major n. sp. of Ochotonidae are described from late Pleistocene cave deposits in the Russian Far East. The description of the new genus was based on thirty-two isolated lower third premolar from the sediments in the Sukhaya and Tetyukhinskaya caves. The new genus was primarily established based on the following characteristics: the triangular anteroconid of the lower third premolar always has a labial fold filled with cement; lingual fold of the anteroconid of the lower third premolar with or without cement; the re-entrant fold(s) on the anteroconid is directed laterally. All of the three new species differ significantly from each other in the size of the lower third premolar.

Strike and dip are essential to the description of geological features and therefore play important roles in 3D geological modeling. Unevenly and sparsely measured orientations from geological field mapping pose problems for the geological modeling, especially for covered and deep areas. This study developed a new method for estimating strike and dip based on structural expansion orientation, which can be automatically extracted from both geological and geophysical maps or profiles. Specifically, strike and dip can be estimated by minimizing an objective function composed of the included angle between the strike and dip and the leave-one-out cross-validation strike and dip. We used angle parameterization to reduce dimensionality and proposed a quasi-gradient descent (QGD) method to rapidly obtain a near-optimal solution, improving the time-efficiency and accuracy of objective function optimization with the particle swarm method. A synthetic basin fold model was subsequently used to test the proposed method, and the results showed that the strike and dip estimates were close to the true values. Finally, the proposed method was applied to a real fold structure largely covered by Cainozoic sediments in Australia. The strikes and dips estimated by the proposed method conformed to the actual geological structures more than those of the vector interpolation method did. As expected, the results of 3D geological implicit interface modeling and the strike and dip vector field were much improved by the addition of estimated strikes and dips.

Shortening styles in salt-influenced basins can vary markedly, with the volume and distribution of salt prior to shortening being a key control. Here we use a suite of physical models to examine styles of thin-skinned regional shortening in settings where the pre-shortening structure comprised minibasins surrounded by salt (‘isolated-minibasin’ provinces). Our models show that the high volume of mechanically-weak salt localizes lateral regional shortening, with shortening inducing salt flow towards the foreland that subsequently contributes to three key processes - translation, tilting and rotation of minibasins. First, we demonstrate that the flowing salt pushes against minibasins, propelling them in the regional shortening direction. Minibasin translation is enhanced by fast-flowing salt streams and impeded by basal friction due to welding and base-salt buttresses. Second, we show how minibasin tilt directions and magnitudes vary spatially and temporally during regional shortening. Minibasins tilt away from zones of pressurized salt, the locations of which may shift due to changes in salt flow regimes. Tilt directions may also change as minibasins pivot on primary welds, or due to forces associated with minibasin collision. Third, minibasins can rotate around sub-vertical axes during regional shortening. We speculate that this rotation is caused by a combination of: i) traction imparted on the minibasin boundary by differential horizontal flow of adjacent salt; and ii) pivoting on primary and secondary welds. We synthesize our results in a series of 3-D conceptual models, before we compare and contrast regional shortening styles and processes in salt-influenced basins with different pre-shortening salt configurations. Our findings contribute to the understanding of the geometry and kinematics of shortened salt basins, as well as a deeper understanding of the tectono-stratigraphic evolution of minibasins.

This research includes structure interpretation of the Yamama Formation (Lower Cretaceous) and the Naokelekan Formation (Jurassic) using 2D seismic reflection data of the Tuba oil field region, Basrah, southern Iraq. The two reflectors (Yamama and Naokelekan) were defined and picked as peak and tough depending on the 2D seismic reflection interpretation process, based on the synthetic seismogram and well log data. In order to obtain structural settings, these horizons were followed over all the regions. Two-way travel-time maps, depth maps, and velocity maps have been produced for top Yamama and top Naokelekan formations. The study concluded that certain longitudinal enclosures reflect anticlines in the east and west of the study area representing Zubair and Rumaila fold confined between them a fold consist of two domes represents Tuba fold with the same trending of Zubair and Rumaila structures. The study confirmed the importance of this field as a reservoir of the accumulation of hydrocarbons.

The geochemistry of the Kuldhar Member Shale (Callovian-Oxfordian), Jaisalmer Formation, western Rajasthan has been investigated to identify the source rock characteristics, palaeoweathering and tectonic setting of the source area. The Kuldhar Member Shale has higher concentration of SiO2, CaO, Fe2O3, Al2O3, K2O and classified as Fe-shale. The positive correlation of Al2O3 with other oxides apart from CaO suggests that these elements are primarily associated with micaceous/clay minerals. The Kuldhar Member Shale shows slightly light rare-earth element (LREE)-enriched and flat heavy rare-earth element (HREE) patterns with negative Eu anomaly, and are similar to granitic rocks from Precambrian Aravalli Craton situated in the southeast and some minor contribution from the Malani Igneous Suits (MIS) in the south of the basin. Provenance modelling indicates that the Kuldhar Member Shale is best modelled with a mixture having 59.5% Aravalli Supergroup rocks, 25% Delhi Supergroup rocks (North Delhi Fold Belt), 14% Banded Gneissic Complex (BGC) and 1.5% Malani Igneous Suits (MIS). The chemical index of alteration (CIA), index of compositional variability (ICV) and the A-CN-K diagram of the Kuldhar Member Shale suggests that the source area experienced moderate to high degree of chemical weathering under warm and humid climatic conditions. The shift of sediment source from distal in the beginning to local during later period suggests sedimentation in a tectonically active basin.

Discoveries of hydrocarbons in the basins of the African Equatorial Margin and Guinea Gulf stimulated the exploratory interest in the basins of the Brazilian Equatorial Margin, for being together before the Continental Drift. This interest emerges because both African and South American equatorial margin are considered analogous. The Barreirinhas Basin is a member of the Brazilian equatorial margin. The objective of this work is to present the results obtained through the seismic interpretation and structural 3D modeling, in the context of gravitational tectonics, in an area covered by 3D seismic data, in the Barreirinhas Basin. The compressional domain of an extensive-compressive system was mapped. In this study, were identified reverse faults, thrust faults and fault-related folding like fault-bend and fault-propagation fold that can be accompanied by backthrust features in deep to ultra-deep waters. The 3D structural model allowed the representation of the geometric variations present in the study area. The new information will be important for the identification and evaluation of structures with greater potential for hydrocarbon accumulations and can help in future studies to characterize the reservoir, contributing to the evolution of knowledge of the equatorial margin, especially in the Barreirinhas Basin.

Although previous studies reported that currents over topographic features, such as seamounts and ridges, cause strong turbulence in close proximity, it has been elusive how far intense turbulence spreads toward the downstream. Here, we conducted a series of intensive in-situ turbulence observations using a state-of-the-art tow-yo microstructure profiler in the Kuroshio flowing over the seamounts of the Tokara Strait, south of Kyusyu Japan, in November 2017, June 2018, and November 2019, and employed a high-resolution numerical model to elucidate the turbulence generation mechanisms. We find that the Kuroshio flowing over seamounts generates streaks of negative potential vorticity and near-inertial waves. With these long-persisting mechanisms in addition to other near-field mixing processes, intense mixing hotspots are formed over a 100-km scale with the elevated energy dissipation by 100- to 1000-fold. The observed turbulence could supply nutrients to sunlit layers, promoting phytoplankton primary production and CO2 uptake. Persistent and intense mixing hotspots are generated where the Kuroshio flows over steep seamounts, with an increase in energy dissipation by two to three orders of magnitude, according to tow-yo microstructure measurements combined with numerical simulations.

The accurate prediction of overpressure before drilling is important for hydrocarbon exploration. It is almost impossible to directly predict the multiple origin overpressures via the existing methods that are related to anomalous porosity in a deep fold-thrust belt. Considering the Kelasu thrust belt (KTB) as an example, the compacting and loading curves in the KTB at the maximum burial period were restored. The measurements of fluid pressure obtained from drill-stem tests carried out at depth were then used to calculate the vertical effective stress offset (ΔVES) away from the restored loading curve. The unknown ΔVES was then predicted using the quantitative relationship between ΔVES, the distance from the axial surface of the fold forelimb or the distance to the thrust fault cutoff (FDIST), and the erosion thickness (ΔH). Finally, the vertical effective stress and overpressure were predicted using the predicted ΔVES, overburden stress, and loading curve. We found that mudstones formed at different rates of deposition would have different loading curves, which is a piecewise function that alternates between convex and concave functions. The convex function is more suitable for describing the loading and compaction behavior of strata with limited porosity strata ( 3.5%) can be better expressed by the concave function. The ΔVES induced by tectonic compression, transfer, and exhumation was found to present an inverse relationship with the FDIST but showed a positive relationship with the ΔH. Compared to Eaton’s method, the method developed in this study produces more accurate results and is, therefore, more appropriate for predicting the overpressure of intense tectonic compression, faulting, and exhumation fields in deep fold-thrust belts.

Overriding the underthrusting Indian plate along the low angle detachment surface of the Main Himalayan Thrust (MHT), the entire Himalayan wedge, consisting of several allochthonous and autochthonous sheets is actively deforming due to ongoing India-Asia convergence. However, the information on active tectonics of autochthonous sheets exposed in tectonic windows has often been eluded due to lack of directed investigations. The present study pertains to the active tectonics of the eastern part of an autochthonous sheet exposed in Kullu-Larji-Rampur window of the Lesser Himalaya. Geomorphic features and statistically analyzed geomorphic indices of Drainage Basin Shape (Bs), Hypsometric Integral (HI), Stream Length-Gradient Index (SL), Transverse Topography Symmetry Factor (T), and Basin Asymmetry Factor (AF) reveal active crustal deformation in the window caused by tectonic activities of spatially varying magnitudes. While the spatial distribution of Bs, HI, and SL suggest differential uplift of the anticlinally folded autochthonous sheet along the MHT, the spatial distributions of AF and T suggest an overall southeastward preferential shifting of the trunk streams of 3rd-order drainage basins of the terrane; the hinge zone and northwestern part of the sheet are experiencing relatively faster uplift. The faster uplift in the northwest has caused an overall southeastward down-tiling of the terrane, and thus preferential stream migration in that direction. The faster uplift of the hinge zone is considered to indicate active tightening of the fold.

The Bengal Basin accommodates an extremely thick Cenozoic sedimentary succession that derived from the uplifted Himalayan and Indo-Burman Orogenic Belts in response to the subduction of the Indian Plate beneath the Eurasian and Burmese Plates. The Hatia Trough is a proven petroleum province that occupies much of the southern Bengal Basin. However, the style of deformation, kinematics, and possible timing of structural initiation in the Hatia Trough and the relationship of this deformation to the frontal fold-thrust system in the outer wedge (namely, the Chittagong Tripura Fold Belt) of the Indo-Burman subduction system to the east are largely unknown. Therefore, we have carried out a structural interpretation across the eastern Hatia Trough and the western Chittagong Tripura Fold Belt based on 2D seismic reflection data. Our result suggests that the synkinematic packages correspond to the Pliocene Tipam Group and the Pleistocene Dupitila Formation. This implies that the structural development in the western Chittagong Tripura Fold Belt took place from the Pliocene. In the Hatia Trough, the timing of structural activation is slightly later (since the Plio-Pleistocene). In general, fold intensity and structural complexity gradually increase toward the east. The presence of reverse faults with minor strike-slip motion along the frontal thrust system in the outer wedge is also consistent with the regional transpressional structures of the Indo-Burman subduction system. However, to the west, there is no evidence for strike-slip deformation in the Hatia Trough. The restored sections indicate that the amount of east–west shortening in the Hatia Trough is very low (maximum 1.2%). In contrast, to the east, the amount of shortening is high (maximum 13.5%) in the western margin of the Chittagong Tripura Fold Belt. In both areas, the key trapping mechanism includes anticlinal traps, although stratigraphic and combinational traps are possible, but this requires further evaluation.

The North China district has been subjected to significant research with regard to the ore-forming dynamics, processes, and quantitative forecasting of gold deposits; it accounts for the highest number of gold reserves and annual products in China. Based on the top-level design of geoscience theory and the method adopted by the National Key R & D Project (deep process and metallogenic mechanism of North China Craton (NCC) metallogenic system), this paper systematically collects and constructs the geoscience data (district, camp, and deposit scales) in four key gold districts of North China (Jiaojia-Sanshandao, Southern Zhaoping, Wulong, and Qingchengzi). The settings associated with the geological dynamics of gold deposits were quantitatively and synthetically analyzed, namely: NCC destruction, metallogenic events, genetic models, and exploration models. Three-dimensional (3D) and four-dimensional (4D) geological modeling was performed using the big data on the districts, while the district-scale 3D exploration criteria were integrated to construct a quantitative exploration model. Among them, FLAC3D modelling and the GeoCube software (version 3.0) were used to implement the numerical simulation of the 3D geological models and the constraints of the fluid saturation parameters of the Jiaojia fault to reconstruct the 4D fault structure models of the Jiaojia fault (with a depth of 5000 m). Using GeoCube3.0, multiple integration modules (general weights of evidence (WofE), Boost WofE, Fuzzy WofE, Logistic Regression, Information Entropy, and Random Forest) and exploration criteria were integrated, while the C-V fractal classification of A, B and C targets in four districts was carried out. The research results are summarized in the following four areas: (1) Four gold districts in the study area have more than three targets (the depth is 3000 m), and the class A, B and C targets exhibit a good spatial correlation with gold bodies that are controlled by mining engineering at depths greater than 1000 m. (2) The Boost WofE method was used to identify the target optimization in 3D spaces (at depths of 3000–5000 m) of the Jiaojia-Sanshandao, Southern Zhaoping, and Wulong districts. (3) The general WofE method is based on the Bayesian theory in 3D space and provides robust integration and target optimization that are suitable for the Jiaojia-Sanshandao and Southern Zhaoping districts in the Jiaodong area; it can also be applied to the Wulong district in the Liaodong area using a quantitative genetic model and an exploration model. Random forest is a multi-objective integration and target optimization method for 3D spaces, and it is suitable for the complex exploration model in the Qingchengzi district of the Liaodong area. The genetic model and exploration criteria associated with the exploration model of the Qingchengzi district were constrained by the common characteristics of the gold fault structure, magmatic rock emplacement in North China, and the strata fold and interlayer detachment structure. (4) Based on the gold reserves and the 3D block unit model of the Sanshandao gold deposit in the Jiaojia-Sanshandao district, the gold contents of the 3D block units in class A and B targets of the ore concentration were estimated to be 65.5% and 25.1%, respectively. The total Au resources of the optimized targets below a depth of 3000 m were 3908 t (including 1700 t reserves), and the total Au resources of the targets at depths from 3000 to 5000 m were 936 t. The study shows that the deep gold deposits in the four gold districts of North China exhibit a strong “transport-deposition” spatial correlation with potential targets. These “transport-deposition” spatial models represent the tectonic-magmatic-hydrothermal activities of the metallogenic system associated with the NCC destruction events and indicate the Au enrichment zones.

Research subject. Large orogenic gold deposits in the fold belts of Central and Northeast Asia.Materials and methods. Geological mapping of various scales on a number of large orogenic gold deposits was conducted using the methods of structural-paragenetic analysis of metamorphic strata, accompanied by obligatory linking of ore mineralization manifestations to specific structures. In a number of cases, various statistical methods were used to geometrize mineralization, identify patterns of its location and determine the paths of paleofluid flows. Available publications on the objects under consideration were reviewed. The geological and structural features of large orogenic gold deposits – Muruntau, Kokpatas, Sukhoi Log and Pavlik – were considered.Results. The Muruntau, Kokpatas and the Sukhoi Log ore deposits are of shariyage-thrust type. Compared to these objects, the Pavlik field is confined to a zone of volumetric fracturing between a series of reverse faults, feathering a large deep fault and belonging to the transpression type. At the Muruntau and Pavlik deposits, the analysis of the location of the most intensive mineralization substantiated the paths of paleofluid flows, along which the fluid migration and ore formation took place.Conclusions. The distribution of ore mineralization in the Muruntau deposit obeys the orientation of planar (cleavage) and linear (orientation of fold hinges) elements. Apparently, the former (main) direction may indicate the orientation and position of the main migration route of ore-bearing fluids, while the latter corresponds to secondary channels, the position of which is due to the intersection of syn-napping structures with favourable lithological horizons. For the Pavlik deposit, the position of ore pillars is compared with the paths of paleofluid flows, the root parts of which are promising for identifying the most powerful and intense mineralization.

Ain Sifni anticline is located in northern Iraq within High Folded Zone. It contains some tectonic deformations that need to study to determine the source and mechanism of these deformations concerning the geological setting of the study area. This study includes structural and morphotectonic interpretations for the Ain Sifni anticline, such as the visual & digital interpretation of satellite images and the Digital Elevation Model interpretation. These parameters are used to identify the morphogenic criteria and subsequently, to conclude a morphotectonic aspect of the deformations in the Ain Sifni anticline. Because of the regional tectonic evolution in this area, the structural and morphotectonic analysis of this anticline shows much evidence of morphological changes at the southeastern plunge area of the anticline within the Injana and Mukdadiya formations in comparison to the northwestern plunge area of the anticline. In addition, two recent water gaps have been recognized at the southeastern plunge area, one is confirmed and the other is proposed, and then a wind gap has been recognized in the middle of the anticline. A relation has been established between these morphotectonic features with the lateral propagation of the anticline towards the southeast, due to the regional tectonic deformation. A significant main fault has also been detected as a dextral strike-slip fault perpendicular to the fold axis of the anticline. This fault caused a difference in the vergency of the anticline and deformed the outcrops of formations in the study region.

The age and geochemical characteristics of alkaline rocks of the Dugda massif (Eastern Tuva), attributed to the East Sayan Late Paleozoic rare-metal magmatic zone, have been determined. The massif is composed of nepheline syenites, which dominate over alkaline quartz syenites and alkaline granites. The age of the rocks has been estimated by the 40Ar/39Ar method for amphibole and the U–Pb SIMS method for zircon. The age of the rocks was 291 ± 5 Ma for nepheline syenites, 284 ± 2 Ma for alkaline quartz syenites, and 285 ± 4 Ma and 287 ± 1 Ma for alkaline granites. These estimations make it possible to determine the age of the massif with an average value of ~287 Ma. Rocks with different compositions are characterized by close geochemical characteristics. They are enriched in the majority of incompatible elements in comparison with the average composition of the Earth’s crust and are characterized by multi-element spectra similar to A-type granitoids. Variations in the contents of the incompatible elements in the rocks of the massif exceed two orders of magnitude and reach ore concentrations (Zr up to 2.5 wt %, Nb up to 0.2 wt %, Ta up to 250 ppm, and Y up to 0.2 wt %). The geological position of the massif and specific features of the composition of its rocks, allowed us, firstly, to clarify the relationship between the East Sayan Late Paleozoic rare-metal zone and the fault system, which defines the western boundary of the Tuva–Mongolian microcontinent; secondly, to limit the time of alkaline magmatism to the interval of 309–285 Ma; and thirdly, to conclude that the spectrum of rare-metal igneous rocks of the zone is not limited to alkaline granitoids, but also includes alkaline nepheline syenites.

New data are reported on the age, composition, and formation conditions of the Late Triassic granitoids of minor intrusions from the eastern part of the Bureya continental massif of the Central Asian fold belt, and their geodynamic interpretation is given. U–Pb geochronological zircon studies indicate that the rocks of the Altakhta syenite–leucogranite complex were formed in two phases within 235–224 Ma. The first phase (235.3 ± 2.9–230 Ma) was responsible for the formation of magmatic rocks that are similar to the А1-type intraplate granitoids in terms of geochemistry and resemble subduction- and collision- related granitoids in terms of REE composition. The second phase (226–224 Ma) produced granites similar to А2-type and А2 + I and S-types. A combination of within-plate and subduction signatures and the presence of A, I, and S-type rocks of similar ages in this complex supports their formation in a transform continental margin setting.

The detection and description of pathological voice are the most important applications of voice profiling. Currently, techniques like laryngostroboscopy or surgical microlarynoscopy are popularly used for the diagnosis of voice pathologies but are invasive in nature. Disorders of vocal folds impact the quality of voice, and therefore, the accuracy of voice profiling is reduced. This paper presents a better solution to differentiate normal and pathological voices based on the glottal, physical, and acoustic and equivalent electrical parameters. These parameters have been correlated using mathematical equations and models. Results reveal that the glottal flow is strongly influenced by physical parameters like stiffness and viscosity of vocal folds in case of pathological voice. However, their direct measurement requires complex invasive medical procedures or costly and complex electronic hardware arrangements in case of non-invasive methods. Glottal parameters, on the other hand, facilitate much simpler estimation of vocal folds disorders. In this work, the authors have presented two non-invasive approaches for better accuracy and least complexity for differentiating normal and pathological voices: 1) by using correlation of glottal and physical parameters, 2)by using acoustic and equivalent electrical parameters.

Integrated petrographical and geochemical analysis of Sawa Formation sandstones was analyzed to reconstruct their source area weathering, paleoclimate, tectonic setting and provenance conditions. Petrographically, quartz is dominant detrital mineral followed by feldspar, mica, rock fragments and heavy minerals. Sawa Formation sandstones have been classified as quartzarenite with subordinate sub-arkose and sub-litharenite type. Major oxide element abundances revealed the sandstones have high SiO2 concentration, high K2O/ Na2O ratio, which is consistent with the petrographic data. These sandstones were derived mainly from stable cratonic with minor collision suture and fold thrust belt source and deposited in rifted continental margin basin setting, reflecting high maturity of sediments and high stability of the source area. The CIA, CIW and PIA values of these sandstones indicate high intensity of weathering condition in the source area under warm and humid climate.

The context of NW–SE plate convergence between Africa and Eurasia led to the development of compressional and extensional structures in the Maghrebian margin. In this study, we investigated the Kechabta molasse basin parts of the northern Tunisian Atlas using the combination of surface and sub-surface data. Our results suggest that Kechabta basin is shaped by E–W to NW-trending grabens and NE–SW fold axes, which are well distributed along a large E–W right-lateral shear zones. During the Late Oligocene–Middle Miocene, the Africa–Eurasia subduction in North Tunisia is accommodated by: (i) the thrust sheets movement in northern Tunisia with an overall southeastward orientation, (ii) the opening of E–W and NW-trending extensional structures in the foreland basin and, (iii) the dextral strike-slip activity of the E–W trending master faults under a trans-tensional regime. Within the Upper Tortonian–Lower Pleistocene period, basin inversion is occurred by a regional NW–SE to NNW-trending compressional event after passing through the continental collision process. This shortening phase gave birth to the major fold structures, reactivated the main preexisting E–W weaknesses and created a local extension along NW-trending faults. The dextral E–W shear zones have a primary role in the distribution of the different tectonic structures in Kechabta basin, they are activated since the Late Oligocene and causing the stress perturbation phenomena. The reorientation of stress trajectories along these active preexisting structures is considered to be responsible for the unusual co-existence of folds and grabens in this Neogene basin under the same compressive regional regime.

The field studies, the Landsat 8 OLI/TIRS processing and the digital elevation model of the Alos Palsar images enabled us to map the lineaments of the Mboula area, in the Adamawa-Yade domain of the Central Pan-African Fold Belt. The use of the OLI 8 band on Landsat 7 × 7 window made it possible to highlight these lineaments. The result depicted in more than 12,417 segments of lines and curves corresponding to potential fractures and geological contacts. Note that the maximum number of main lineaments after treatment (3,274 lineaments) are oriented NE-SW. The second lineament trend in the study area is NNE-SSW and NNW-SSE respectively. The DEM of the Alos Palsar sensor made it possible to establish four geomorphological units in the study area: hilltop, mountain, plateau and alluvial plain. By superimposing these on the lithological map and tectonic, the coincidence is quite obvious. Thus, field and remote sensing analysis reveal that lithology and the CCSZ have influenced significantly the geomorphological evolution of the Mboula area. These results also illustrate the interest of remote sensing analysis in mapping tectonic structures, with benefit of time saving and precision.

Albania is located in the Alpine fold belt extending to the central part of the Dinarides–Hellenides arc in a zone characterized by intense tectonic-seismic activity that has a considerable influence in shaping the geo-environment of the area. Historically, strong earthquakes occurred in this region and triggered lots of mass movements causing considerable damages such as life loss, destruction of properties and disruption of the geo-environment. This paper introduces several earthquake-triggered mass movement events in Albania that occurred during 1850–2019. It was achieved through collection and analysis of data from historical studies and authors’ field investigations. The results show that soil type, slope inclination and seismic activity have a direct influence in the occurrence of these movements consistent with similar parameters occurred worldwide. Earthquake’s magnitude and degree of mass movement is well correlated. Mass movements such as lateral earth spread, rock fall, debris slides, sand boils, sand fluidization, cracks and settlement were triggered by earthquakes with a magnitude of 6.0 or higher. On the other hand, lateral rock spread needs a higher seismic magnitude to occur.

The Ireviken Event was the first Middle Paleozoic event consisting of synchronised faunal, isotopic and facies change to be recognised. An analysis of the conodont faunas throughout the Boree Creek/Borenore Limestone succession in the central western region of the Tasman fold belt of New South Wales (Australia) revealing all five conodont zones that comprise the event is presented. While some zonal boundaries are precise, allowing direct comparison of stratigraphic intervals on other paleo-continents, some can only be approximated. Conodont data from pre-Ireviken Event strata, in contrast, only permit the identification of a broad Telychian chronology. The identification of Wenlock post-Ireviken Event conodont zones is incomplete due to lithological variability, namely the presence of tuffaceous beds near the top of the formation and an unconformity between the Boree Creek and overlying Borenore Limestone. The Boree Creek Formation contains the only example of the Ireviken Event discovered to date from the Tasman fold belt of eastern Gondwanaland.

The Central Uplift in the Songliao Basin is a large consequent buried-hill structural belt between the east and west faulted zones. Some hydrocarbon-rich sags (e.g. Xujiaweizi and Changling), occur at both sides of the uplifted zone. The Central Uplift, which indicates richness in hydrocarbon resources, is a long-term hydrocarbon migration destination with favorable conditions for hydrocarbon accumulation. Drilling two risk-taking exploratory wells, LT2 and LP1, have been demonstrated by the recent breakthrough in hydrocarbon discoveries. In conformity with uplift-sag contacts and migration pathways, the researchers establish six accumulation models, namely dual consequent faults, dual antithetic faults, consequent-antithetic faults, consequent fault-consequent overlap, antithetic fault-consequent overlap, and dual consequent overlaps, and five carrier systems which include the fault-fracture network, sandy conglomerate-fault-fracture network, fault-unconformity-fracture network, sandy conglomerate-unconformity-fracture network, and sandy conglomerate-fault-fracture network-unconformity. The team divides the Central Uplift accumulation process into four stages, including fold basement denudation and leveling off, coupled weathering, and leaching in the faulted and uplifted zones, hydrocarbon accumulation with sealed overburden, and sustained hydrocarbon preservation in the Central Uplift. Based on an analogous study of hydrocarbon accumulation in the Central Uplift, they conclude that the salients between hydrocarbon-rich sags occurring in the fault subsidence period are similar in accumulation conditions to the Central Uplift. The buried hills and their internal configuration at the salients should be the focus of exploration since they are the strategic successors of hydrocarbon exploration in the Songliao Basin due to their excellent exploration potential.

Although reservoir characterization has been carried out by many researchers on the sedimentary package of the Bengal basin hydrocarbon province, integration of petrophysical and seismic sequence-based reservoir evaluation is rarely taken into account. This paper focuses on the identification of gas zones, reserve estimation and identification of new prospects in Srikail gas field within the eastern fold belt of Bengal basin integrating four wireline logs and 2D seismic data. Our study finds seven hydrocarbon-bearing zones (A, B, C, D, E, F and G) within the measured depth between 2429.5 and 3501 m. Petrophysical properties of seven hydrocarbon-bearing zones indicate that they are good quality reservoir sands. The gas horizons were mapped on seismic sections which reveal that the NW–SE anticlinal structure is largely affected by channels in the crest and western flank. The channels are infilled by fine-grained sediments which act as cap rock on northern and western parts of the structure. Thus, the anticlinal structure and fine-grained sediments make a potential trap for hydrocarbon accumulation and laterally and vertically well-distributed sequence remnants are the main reservoir rocks in this area. Volumetric reserve estimation of these sands provided a total gas initially in place as 552 billion cubic feet. Moreover, all the four wells are drilled in the southern block of the structure, and since there is a structural continuity from south to the north, it is highly recommended to drill a well up to 3000 m depth in the northern block to test its hydrocarbon potentiality. Overall, the outcomes of this study contribute new insights for reservoir characterization and identification of new prospects in an efficient way.

Based on the dating of metamorphic and igneous rocks of the northeastern part of the Khamsara terrane, the main stages of tectono-magmatic activity at the border of two large structures—the Central Asian fold belt (CAFB) and the Siberian craton—have been established. The formation of the initial volcanogenic–sedimentary formations of this terrane, which mark the continental-marginal stage of development, took place in the range of 680–640 Ma. The age of accretion–collisional events in the CAFB fragment adjacent to the Siberian platform is fixed by the intrusion of postcollisional granitoids with an age of 480 Ma. Subsequent manifestations of Ordovician intraplate volcanism (464–462 Ma) are associated with the decay of the collisional orogen under the conditions of incipient rifting. Another stage in the development of this block is also associated with the processes of intracontinental extension and is represented by Late Paleozoic basic volcanism with an age of 267 Ma. The first established manifestations of rifting processes of different age levels within the fragment of the CAFB considered are associated with its location on the border of large inland structures separated by faults that retain their activity for a long time.

The article presents new data on ages (U-Pb zircon dating, SIMS SHRIMP-II) and chemical compositions of rocks from gabbro-granitic and granite-leucogranitic magmatic associations. These rocks preceded the formation of Li-enriched spodumene pegmatites of the Tserigiyngol-Burchin ore cluster (Russian: ЦБРУ), one of the main clusters in the South Sangilen pegmatite belt (SSB) located in the Tuva-Mongolian massif being a part of the Central Asian Fold Belt. We investigated the rocks from the Upper Tserigiyngol, Uchuglyk and Temenchulu plutons, and pegmatites from two neighbouring fields. We distinguish three impulses of granitic magmatism (517±7, 508±7, and 488±6 Ma), which are attributed to different stages of the Early Paleozoic collision orogeny (520-480 Ma). The period when the Li-enriched pegmatites were formed (494±7 Ma) is close to the magmatism impulse at 488±6 Ma. Differences are discovered in compositional and isotopic (Sm-Nd) features of granites dominating at the following stages of collisional orogeny: (1) early collision (517±7 Ma) – I-type granites, eNd(T)=0–1.5, TNd (DM-2st)=1.2–1.1 b.y., and (2) late collision (488±6 Ma) – A-2-type granites, eNd(T)=–3.0…–1.6, TNd (DM-2st)=1.5–1.4 b.y., which are due to different sources. Our study shows that facies transitions are absent between the late-collision granites (488±6 Ma) and the spodumene pegmatites from the Tserigiyngol-Burchin ore cluster (494±7 Ma), although these rocks are close in age. In terms of geochemical features, the spodumene pegmatites from the cluster are strongly different from both the late-collision granites and spodumene pegmatites from other SSB fields, including the large Tastyg lithium deposit. We have analysed the role of interactions between the crustal and mantle materials in the formation of granitoid sources in the Tserigiyngol-Burchin ore cluster, and described their evolution in time and the influence on the pegmatite rare-element specialization.

Jhelum Fault is the north–south-oriented major structural lineament originating from the Hazara-Kashmir Syntaxis and extending southwards towards the Mangla Lake. Geographic extent, nature and significance of Jhelum Fault are the subjects which have been approached by different researchers in the past. The previous research provides enough evidence for the presence of Jhelum Fault as well as they discourse its surface extent. None of the previous research addresses the subsurface model of this fault; consequently, its surface extent has been ambiguous and variably reported. The current research takes into account both the surface lineament as well as the subsurface behaviour of the deformed strata to draft the most reasonable depiction of this fault. Field data were coupled with satellite image of 1.5 m ground resolution to produce the geological map of the study area at 1:25,000 scale. The subsurface model was created along four traverse lines by considering the lateral extent of the structures and their shifting trends on the geological map. The stratigraphic package was taken from the nearby hydrocarbon exploratory well data (Missakeswal-01 well of OGDCL) as no rocks older than middle to late Miocene were exposed in the area. The consistent through-going map extents of many faults in the study area prove that faults are playing the major role in the tectonic evolution of the Jhelum Fault Zone. In the subsurface model, the same faults show very little stratigraphic throw, which signify the major stress component to be associated more with wrenching than pure compression. Therefore, most faults in the area are of transpressional nature having dominant lateral component with relatively smaller push towards west on steeply east dipping faults. The model also shows the positive flower structure with dominantly west verging fault system with few east verging back thrusts. The subsurface proposed model shows that the Jhelum Fault is extendible southwards to the Mangla Lake in the subsurface; however, it acts like a continuous shear zone on the surface where there all the shearing is accommodated by tight refolded fold axes. The east–west shortening does not exceed 14.5% which shows smaller compression in the study area. The 3D model further clarifies the model by showing the consistency of the fault system along strike.

Naturally, fractured reservoirs play a considerable part in the study, production, and development of hydrocarbon fields because most hydrocarbon reservoirs in the Zagros Basin are naturally fractured. Production from those reservoirs is usually affected by the presence of a system of connected fractures. In this study, the Tabnak hydrocarbon field on the fold–thrust belt at the Zagros zone in the Persian plate has been analyzed by the facies models, folding mechanism analysis to identify fracture reservoir patterns. The results show a flexural fold with similarity in the folding mechanism and some open fracture potential made by limestone, shale, clay, and anhydrite in the study area's facies models. Consequently, the stress pattern and type of fracture issue on the fold's upper and lower layers will be similar. On the Tabnak anticline reservoir using image processing techniques in MATLAB R2019 software and kriging geostatistical methods, fracture surface patterns as a block model extended to the depth. Using the model results, fractures’ orientation distribution in adjacent wells 11, 14, and 15 is appropriate. The results also have similarities with the facies models, folding mechanism assessment, well test, and mud loss data analysis. These results can affect the development plans’ primary approach by drilling horizontal and sleep wells and hydrocarbon reservoir management strategies.

In this study, morphotectonic analyses were prepared for an anticline existing to the north of Maqloub Anticline and extends toward north - south approximately, which is unfamiliar in relation to the major extension of the anticlines in the region. The study involves a structural interpretation of the anticline's origin and its relation with the faulting in the foreland zone in this area, specifically in foothill zone, because of the major fracture that is found adjacent and parallel to the axis of this anticline. The visual interpretation is the major tool used to determine the features of this anticline. Moreover, some facilitating remote sensing technologies, such as digital processing of satellite images and Digital Elevation Model data, were utilized to verify the shape of this geological feature. The origin of the fold was discussed through its relationship to the associated fault within the general tectonic framework and the surrounding areas. This study addresses the tectonic mechanism of the anticline as a fold-related fault mechanism. As a result, and through the compilation of the above interpretations, a final geological map was prepared for this anticline, along with a 3D model demonstrating its mechanism of folding. Proposed names were given to the anticline and the fault, which are Mahad Anticline and Mahad Fault , according to the name of their nearest town (Mahad Town).

Late Cenozoic was a period of large-scale extension in the Aegean. The extension is mainly recorded in the metamorphic core complexes with little data from the sedimentary sequences. The exception is the Thrace Basin in the northern Aegean, which has a continuous record of Middle Eocene to Oligocene marine sedimentation. In the Thrace Basin, the Late Oligocene–Early Miocene was characterized by north-northwest (N25°W) shortening leading to the termination of sedimentation and formation of large-scale folds. We studied the stratigraphy and structure of one of these folds, the Korudağ anticline. The Korudağ anticline has formed in the uppermost Eocene–Lower Oligocene siliciclastic turbidites with Early Oligocene (31.6 Ma zircon U–Pb age) acidic tuff beds. The turbidites are underlain by a thin sequence of Upper Eocene pelagic limestone. The Korudağ anticline is an east-northeast (N65°E) trending fault-propagation fold, 9 km wide and 22 km long and with a subhorizontal fold axis. It is asymmetric with shallowly-dipping northern and steeply-dipping southern limbs. Its geometry indicates about 1 km of shortening in a N25°W direction. The folded strata are unconformably overlain by Middle Miocene continental sandstones, which constrain the age of folding. The Korudağ anticline and other large folds in the Thrace Basin predate the inception of the North Anatolian Fault (NAF) by at least 12 myr. The Late Oligocene–Early Miocene (28–17 Ma) shortening in the Thrace Basin and elsewhere in the Balkans forms an interlude between two extensional periods, and is probably linked to changes in the subduction dynamics along the Hellenic trench., TÜBİTAK, İTÜ-BAP, TÜBA, Freie Universität Berlin (1008)

Erinpura Granites form the basement for the Neoproterozoic Malani Igneous Suite in NW India. Based on this study, the Erinpura granites can be divided into Erinpura-East (gneissic fabric), a belt p...

This article presents U–Th–Pb and Lu–Hf detrital zircon isotope data, as well as whole-rock Sm–Nd isotope data on metasedimentary rocks from the eastern part of the Tukuringra Terrane. Our analyses show that the zircons in metasedimentary rocks are mostly early Mesozoic. The Early Mesozoic, Early Paleozoic and Neoproterozoic zircons are predominant and Early Precambrian zircons are almost absent in these rocks. The age of the youngest zircon population places a lower age limit of sedimentation at 204 Ma for the Tungala Formation (Upper Triassic, Rhaetian), at 181 Ma for the Dugda Formation (Lower Jurassic, Toarcian), and at 189 Ma for the Tangomen Formation (Lower Jurassic, Pliensbachian). Practically all Mesozoic, Paleozoic, and Neoproterozoic zircons are characterized by Neo- and Mesoproterozoic Hf-model ages (tHf(DM)) = 1.41–0.46 Ga, tHf(C) = 1.55–0.49) and Mesoproterozoic Nd-model ages (tNd(DM) = 1.25–1.10 Ga, tNd(C) = 1.31–1.14). These results indicate that the sedimentary rocks were mainly sourced from the Amur continental superterrane, but not from the southern framing of the North Asian Craton.

Recent studies of the stress state of the Earth’s crust and rates of plate movement of the Caucasian fold system with respect to the Eurasian continent, analysis of sources of underwater degassing and volcanism, as well as seismological modeling, suggest that combination of these processes has a positive effect on replenishment of hydrocarbon resources in the Black Sea–Caspian Sea region: they activate the fluid–dynamic systems of the region. The replenishment of hydrocarbon resources is associated with restoration of the energy state of hydrocarbon deposits at various stages of their development and physicochemical fluid–dynamic factors. The broad generalization, seismological modeling of mud volcanoes, and analysis of different-scale factual material allow us to argue that current sources of hydrocarbon generation–natural laboratories and technological lines for converting fluid accumulations into industrial energy and chemical raw materials for industrial application are functioning in the depths of the Black Sea–Caspian Sea region. We consider hydrocarbon deposits as a product of the functioning of such natural, technological lines.