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

A set of wedge-shaped strata overlying the Xuefeng tectonic interface deposited in a cold climate during the Nanhua Period has been developed in eastern Guizhou province, western Hunan province, and northern Guangxi Zhuang autonomous region. These wedge-shaped strata distribute along the rift basins of Hunan, Guizhou, and Guangxi, crossing the southeastern edge of the Upper Yangtze Block and the southwestern segment of the Jiangnan Orogenic Belt. The scope and distribution characteristics of paleoshoreline changes, paleocurrent directions, and paleogeographic features were inferred via comparative studies of typical lithofacies stratigraphic sections at different locations within the region as well as conducting research on depositional facies and microfacies. This research reconstructs the lithofacies paleogeography and sedimentary models of the basin evolution at different stages. Lithofacies paleogeographic features indicate that the study area is in a rift cover deposition period during the Nanhua Period, with basin filling evolution divided into three stages: uplift and erosion with early glacial till deposition, interglacial filling stage, and late glacial till deposition stage. The Nanhua glaciation (Chang'an and Nantuo glaciations) involves glacial, preglacial, and postglacial gravity flow deposits. The interglacial period, especially the Fulu interglacial, is dominated by fluvial, lagoon, and deltaic deposits, with the development of manganese-bearing clastic rock deposits. This research provides new fundamental data for studying the rift basin filling evolution, lithofacies paleogeographic features, and mineralization effects in the Hunan-Guizhou-Guangxi rift basin and also sheds some light on the stratigraphic understanding, mineral exploration, and the tectonic geological background study of its formation. [ABSTRACT FROM AUTHOR]

This contribution presents for the first time a digital elevation map and 1:50,000 scale geological map of Sitagota syncline, Khairagarh Group, which is spread in around 1000 km2 area in the north Bastar Craton (survey of India toposheets 64 C/11 and C/15). We report for the first time, exposures of Algoma-type banded iron formation, intertrappean shale, and oxide and sulphide mineralization in Mangikhuta basalt. Mafic enclaves are reported in the Dongargarh granite. Geochemistry and petrogenetic study of Mangikhuta and Kotima volcanics of Khairagarh Group is presented. Although field investigation and digital elevation map reveal Khairagarh volcano-sedimentary sequence underwent more than one phase of orogeny, the ubiquitous presence of very low-grade metamorphic mineral assemblages in volcanic rocks indicates they did not undergo high P–T transformation and most of the alteration and metamorphism took place at near-surface conditions. Our tectonomagmatic model proposes the occurrence of a rift basin in the north Bastar Craton from 2.46 to 2.2 Ga, resulting in sedimentation and high-Mg basalt to basaltic-andesite magmatism. The genesis of Sitagota syncline is attributed to closure and deformation of this rift basin due to compressive forces, probably related to Paleoproterozoic Dongargarh Kotri mobile belt and Mesoproterozoic central Indian tectonic zone. Tectonomagmatic and geochronological similarity of Khairagarh Group to Lower Wyloo Group of Ashburton basin in Pilbara Craton and Hekpoort and Ongeluk basalt formations of Transvaal basin in Kaapvaal Craton indicates Bastar Craton was part of Vaalbara supercontinent in Paleoproterozoic times. [ABSTRACT FROM AUTHOR]

The Late Ediacaran Dengying Formation, located in the Sichuan Basin of the northwestern Yangtze Craton, is of significant interest in oil and gas exploration due to its abundant pores and vugs within microbial mound-shoal complexes. However, there is still uncertainty regarding the spatiotemporal distribution and controlling factors of the platform margin. This study comprehensively analyzes the retrogradation pattern of the Dengying Formation platform margin using seismic data, well logs, field outcrops, and petrological characteristics. Our findings reveal that the Dengying Formation strata surrounding the rift basin at the northwestern of the Yangtze Craton can be divided into three main depositional facies: basin facies, slope facies, and platform margin facies. Additionally, based on the integration of lithological, log, and seismic characteristics, the Dengying Formation is subdivided into four thirdorder sequences, with five sequence boundaries and three seismic facies identified. Supported by sequence stratigraphy and geophysical data, we have reconstructed the tectono-sedimentary evolution of the multiple platform margins on the eastern side of the Deyang-Anyue rift in the Sichuan Basin during the late Ediacaran. Our findings indicate that the platform underwent two phases of retrogradation. The second-stage platform margin underwent retrogradation towards the interior, spanning a distance between 10 and 80 km, based on the initial configuration established by the first-stage platform margin. The main controls for progradation and retrogradation of carbonate platforms are eustatic sea-level changes and tectonic activity. Eustatic sealevel changes can be divided into constructive and destructive phases. Constructive phases are commonly observed in highstand systems tracts, while destructive phases are often associated with transgressive systems tracts and are related to platform retrogradation processes. However, sea-level changes alone cannot fully control the process of platform retrogradation. The thermal subsidence following mantle plume events likely played a significant role in the retrogradation of the platform in the study area. During this period, tectonic processes controlled the geometry of the platform and the deposition of carbonates in the platform margin-slope-basin environment. Additionally, karst-related mound-shoal complexes developed extensively along the platform margin of the Dengying Formation in the northwestern Yangtze Craton. The Lower Cambrian dark shales represent high-quality hydrocarbon source rocks, while the Dengying Formation exhibits an optimal source-reservoir configuration. [ABSTRACT FROM AUTHOR]

Inherited rift topography controls the sediment routing, timing of sand supply, and sedimentary linkage of early post‐rift depocentres. Exhumed examples of early post‐rift turbidite systems are rare and previous studies have examined the evolution of individual depocentres; in contrast, the detailed evolution of early post‐rift turbidite systems across multiple depocentres has never been documented. Current fill‐and‐spill models do not detail the stratigraphic architecture and evolution of sedimentological characteristics of multiple intraslope fans developed across topography, including bed type distributions. Here, the evolution of three intraslope fans that developed across two early post‐rift depocentres is documented along an 18 km long transect in the southern Neuquén Basin, Argentina. The relative chronology of sand supply in depocentres is constrained with new U–Pb ages, and sediment source areas with provenance analysis. The early post‐rift intraslope fans record progradation of the system and progressive sedimentary linkage of post‐rift depocentres, transverse to local syn‐rift structures, with sediment routing subparallel to the cratonic basin margin. The large‐scale stratigraphic architecture of intraslope fans indicates an evolution as a fill‐and‐spill system, with initial confinement through flow stripping and overspill to spillover with erosion and bypass across a transverse topographic high separating the depocentres. Changes in early post‐rift intraslope fan characteristics, including thickness, sandstone content, lobe complex stacking patterns, stratal termination patterns and bed type distribution, record changing confinement through time within a depocentre, and spatially across depocentres. The strong spatial and vertical stratigraphic variability of transitional flow deposits and hybrid event beds reflects enhanced erosion, sediment bypass and flow transformation across transverse relief between the two depocentres during the spillover phase. These findings advance current understanding of early post‐rift turbidite systems and refine fill‐and‐spill models, which will help the prediction of spatial and vertical changes in rock quality and connectivity in subsurface hydrocarbon reservoirs and CO2 storage sites. [ABSTRACT FROM AUTHOR]

The Brazilian Equatorial Margin (BEM) is interpreted as a transform margin, where the last segment opened during Gondwana rifting. However, margin evolution, and break‐up age remain unconstrained. We interpret >10k km of crustal‐scale seismic images extending along ∼600 km of the margin calibrated with drillholes. We determine the style and timing of tectonics across the rift system. We link changes in crustal‐scale structure and age of sediment deposits to interpret variations with the style of extension and intensity of thinning across the BEM. Observations support a rift evolution where deformation is initially distributed forming a shallow basin, subsequently focusses, and later migrates basin‐ward forming the deep‐water domain. We interpret that tectonic activity started ∼140–136 Ma and stopped earlier in the shallow basin causing minor thinning, than in the deep‐water domain with a ∼60 km wide area with 4–8 km thick crust extended in Late Aptian to Early Albian (116–110 Ma). Constraints from seismic and drilling help define an abrupt continent to ocean transition (COT) where continental crust may be abutted by oceanic crust, and breakup occurred at early Albian time. Basin sedimentation from the onset to the Late Aptian is continental, indicating an isolated environment disconnected from Atlantic oceans. During late‐most Aptian to Early Albian basin sedimentation changes and indicates a comparatively rapid marine water infill. Rifting of the BEM is not dominated by transcurrent deformation as previously inferred, with strike‐slip faulting limited to comparatively small sectors, whereas most of the margin extended by normal faulting deformation. Plain Language Summary: Rifting occurs when stretching of continental lithosphere causes its extension and thinning. When extension continues, it leads to break‐up and the generation of a new spreading center. The basin is then split into two conjugate margins that diverge from each other as oceanic spreading creates new seafloor. Rifted margins attract studies as they host resources and may play a role in the impending energy transition. However, the vast majority of rifted margins are insufficiently studied. We have investigated the Brazil Equatorial Margin (BEM), the last region linking Africa and South America during Gondwana breakup, using a large seismic and drillholes data set released by industry. We investigated the tectonic structure and the sediment deposits, and how their joint analysis provides the information to unravel the history of deformation and the processes shaping rifting. Our interpretation supports that the opening of the margin was dominated by normal faulting kinematics rather than the transform‐type deformation previously inferred. Lithospheric deformation initiated with widespread distributed extension and was followed by localization of deformation causing focused thinning. Faulting later migrated basin‐ward creating <10 km thick crust forming a 50–70 km wide region. Break up and the first oceanic crust are possibly Earliest Albian time. Key Points: Newly available seismic and drillhole information provide a novel view into the development of the Brazil Equatorial MarginWe provide a new conceptual model for rifting and ages for the different processes involved, including breakup and Continental Ocean Transition formation and ageWe propose a rift model in which deformation starts distributed, later localizes, and finally faulting evolves sequentially to break up [ABSTRACT FROM AUTHOR]

The Amazonian Craton is home to many Statherian to Calymmian taphrogenesis events that evolved over Large Igneous Provinces. The NW-SE faults on the Western Amazonian Igneous Belt (1.82–1.74Ga) and their reactivations, which facilitated the deposition of the Beneficente Group (1.76–1.60Ga), Prainha Formation (1.46Ga), and Alto Tapajós Group (Silurian-Devonian), are associated with these events in the southwest Amazonian Craton. Mineralogical composition, whole-rocks geochemistry, and Nd-Sr-Pb isotopic data show that the three sedimentary successions originated in the provinces of Rondônia-Juruena and Tapajós Parima, particularly during two rift stages. Beneficente Group deposition is associated with Paleoproterozoic Rift 1, while the Prainha Formation represents the post-rift 1, and Alto Tapajós Group deposition is associated with Paleozoic Rift 2. In addition, the Prainha Formation also received sediment supply from the Sunsás Province. These three sedimentary successions have an intrinsic relationship with the reworking of the local basement and their own reworking that occurred from the Paleoproterozoic to the Paleozoic. Autochthonous reworking, particularly in the Colíder and Beneficente groups, is demonstrated by Ti-magnetite grains, volcanic and arenite fragments in the Prainha Formation sublitharenite, and by angular microcline grains, high Au content, a Pb whole-rock isochron yielding the 1.796±0.096Ga age, and by ${\varepsilon _{Sr\left(0 \right)}}$ ε Sr 0 vs 1/Rb relationship in Alto Tapajós Group. ${\varepsilon _{Nd\left(t \right)}}$ ε Nd t and flat REE patterns and some positive Eu anomalies in the Prainha Formation and Alto Tapajós Group record the influence of the mafic rocks of the Mata-Matá suite. A Pb-Pb whole-rock isochron allowed hydrothermal activity recognition at 1.32Ga in the Vila do Carmo Formation. This event was ratified by positive Eu/Eu* (1.3–1.43), Ce/Ce* (1.24–2.84), and Gd/Gd*(~1.5) anomalies. Finally, Nd model ages, geochemistry, and Sr isotopes allow for correlating the local basement and the overlaying sedimentary successions along the Columbia and Gondwana boundaries. [ABSTRACT FROM AUTHOR]

Objective The Yogou Formation source rock is an important Late Cretaceous source rock series in Termit Basin, Niger. Due to the lack of systematic research on the burial history, thermal evolution history, and hydrocarbon generation history of this set of strata, the understanding of oil and gas accumulation rules in this area is restricted. Methods In this paper, the thermal evolution history of the Yogou Formation source rocks in Termit Basin is restored by using the hydrocarbon generation dynamics model in BasinMod basin simulation software, combined with drilling wells, two-dimensional seismic profiles, and geochemical data. The thermal evolution characteristics of source rocks in different areas and their matching relationship with hydrocarbon accumulation are analysed, which provides important evidence for the next exploration of the Termit Basin. Results The results show that the heat flow value of Termit Basin has obvious two-stage evolution characteristics. The initial heat flow value is low and reaches maximum values in the Late Palaeogene (ranging from 64.3 to 69.2 mW/m2). Since the Neogene, the thermal state of the basin has been characterized by continuous cooling, and the current heat flow value is between 60.7 and 67.4 mW/m2. The hydrocarbon generation of the top Yogou Formation began at 55 Ma (Ro=0.5%), and the main hydrocarbon generation window (Ro=1.0%) started at 35 Ma and reached a high maturity level (Ro=1.3%) at 27.5 Ma. Two stages of hydrocarbon generation are found in the source rocks of the Yogou Formation; in particular, the Late Cretaceous (70-60 Ma) hydrocarbon generation stage mainly exists in the deep area depression of the basin, while the Palaeogene (40-20 Ma) is the main hydrocarbon generation stage of the whole basin. Compared to different tectonic belts show that the source rocks of the Dinga Depression are characterized by high maturity, earlier hydrocarbon generation, and stronger hydrocarbon generation, which are beneficial for providing sufficient hydrocarbons. The strong activity of the Palaeogene faults led to the migration and accumulation of oil and gas generated by the bottom source rocks into the Palaeogene reservoirs. Conclusion The research results can provide a basis for the evaluation of the hydrocarbon generation potential of source rocks in the Termit basin and provide theoretical guidance for oil and gas exploration in the basin.

The Silves Group of the Lusitanian Basin in Portugal represents the initial infill of the continental rifting basins that formed during the breakup of northern Pangaea regions. Evaporites, especially halite, mark the transition from continental to marine settings and the beginning of the deposition in passive margin basins. This work presents the results of the palynostratigraphic and palynofacies analysis of two partial sections from the Pereiros Formation at the top of the Silves Group. The two sections are composed of sandstones, mudstones and dolostones interpreted as deposited in fluvial and lacustrine settings without apparent marine influence. The palynological content is diverse and wellpreserved, dating both sections to the early Hettangian (Lower Jurassic), indicated by the presence of spores Ischyosporites variegatus, Kraeuselisporites reissingeri, Porcellispora longdonensis and the pollen grains Perinopollenites elatoides and Pinuspollenites minimus. The palynological content of one of the sections (Lamas I) is noticeable by microforaminifera linings, suggesting evidence for a hitherto marine incursion at this age in the Silves Group stratigraphy. The beds that yielded the microforaminifera linings are interpreted as having been deposited in an estuarine-type setting, created by the first and short-lived marine transgressive event in the Lusitanian Basin during the early Hettangian.

Neoproterozoic strata are widely developed in the Upper Yangtze region of South China, among which the Sinian Dengying Formation has been discovered with numerous large gas fields in the Sichuan Basin, and hence they have become an essential domain for natural gas exploration and development. The early‐to‐middle Neoproterozoic Nanhua System and Doushantuo Formation are characterized by rifting deposits in the northeastern margin of Sichuan Basin, but their depositional succession and sequence architectures are still unclear, which has largely restricted our understanding of the resource potential of these strata. In this paper, based on the outcrops of the Neoproterozoic Nanhua System and Doushantuo Formation in the northeastern margin of Sichuan Basin, we describe the stratigraphic distribution and sedimentary evolutionary characteristics, and establish the regional stratigraphic framework, sedimentary cycle and evolutionary sequence of the Nanhua System and Doushantuo Formation. The results show that the lithology of the Nanhua System and Doushantuo Formation is primarily composed of conglomerate, conglomeratic sandstone, medium‐fine sandstone, siltstone, mudstone, shale and tillite; a variety of sedimentary facies including alluvial fan, river, delta, coastal shore, shelf, basin and tillite were developed; five third‐order sequences could be identified, representing multiple cycles of marine transgression and regression. The climate during the deposition of the Nanhua System and Doushantuo Formation underwent from a warm and humid pre‐glacial period through cold and arid multiple glacial periods to a warm and humid interglacial period, which consequently formed a sedimentary sequence of alluvial fan and fluvial delta to tillite during the early period, shelf basin to tillite during the middle period and slope basin to delta facies during the late period. In terms of a plan view, the depositional pattern is composed of alluvial fans and deltas at the proximal part of the rift, deep‐water shelf to slope at the middle part of the rift and slope to basin facies at the central part of the rift. Finally, we propose that large‐scale distribution of high‐quality source rocks developed in the interglacial Datangpo and Doushantuo formations, while fluvial‐deltaic reservoirs occurred in the Gucheng, Nantuo and Doushantuo formations, thus showing favourable resource potential and exploration prospects within the Sichuan Basin. [ABSTRACT FROM AUTHOR]

Upper Palaeozoic lacustrine basin deposits not only record local tectonism but are also an archive to evaluate global palaeoclimate changes linked to the Late Palaeozoic Gondwanan ice age. The Tournaisian Horton Group of Nova Scotia, south‐east Canada, accumulated in rift basins following the final accretion of peri‐Gondwanan terranes to the Appalachians. Sedimentology, mineralogy and geochemistry of the well‐exposed sandstones and shales at the classic Blue Beach section (ca 353.5 to 352 Ma) reveal the interplay of local tectonism and global climatic controls on lacustrine sedimentation. The lacustrine depositional environment gradually transitioned from deep water offshore at the base of the section to wave‐dominated and fluvial‐dominated nearshore at the top. Multiple small transgressive–regressive sedimentation cycles have an average 21 ka duration, likely related to Milankovitch cyclicity. Unusually abundant soft‐sediment deformation structures and landslides are the sedimentary responses to frequent earthquakes during the most active phase of rift subsidence. The overall succession shows changes from a shallowing‐up balanced‐filled to an overfilled lacustrine basin. The chemical weathering intensity index and the Th/K ratio show a longer‐term trend from dry and cool conditions low in the section to humid and warm conditions near the top, with rapid change in the transition period. The section records the peak of the global mid‐Tournaisian carbon isotope excursion and the corresponding cooling event (354 Ma to approximately 351 Ma). The sedimentary succession is a response to long‐term and short‐term climatic cycles influencing lake level and sediment supply during the time of maximum rift basin subsidence recorded by the soft‐sediment deformation structures. [ABSTRACT FROM AUTHOR]

Rift basins typically comprise three main tectono-stratigraphic stages; pre-, syn-and post-rift. The syn-rift stage is often characterised by the deposition of asymmetric wedges of growth strata that record differential subsidence caused by active normal faulting. The subsequent post-rift stage is defined by long-wavelength subsidence driven by lithospheric cooling and is typified by the deposition of broadly tabular stratal packages that drape any rift-related relief. The stratigraphic contact between syn-and post-rift rocks is often thought to be represented by an erosional unconformity. However, the late syn-rift to early post-rift stratigraphic record is commonly far more complex since (i) the associated tectonic transition is not instantaneous; (ii) net subsidence may be punctuated by transient periods of uplift; and (iii) strain often migrates oceanward during rifting until continental breakup is achieved with crustal rupture. Previous publications on the Eastern Brazilian marginal basins have not historically used the tripartite scheme outlined above, with the post-pre-rift interval instead being subdivided into rift, sag and passive margin tectono-stratigraphic stages. In addition, the sag stage has been previously described as late syn-rift, early post-rift or as a transition between the two, with the passive margin stage being equivalent to the classically defined post-rift, drift stage. Two (rather than one) erosional unconformities are also identified within the rift-to-sag succession. In this work, we use 2D and 3D seismic reflection and borehole data to discuss the expression of and controls on the syn-to post-rift transition in the shallow and deep water domains of the south-central Campos Basin, south-east Brazil. We identified three seismic-stratigraphic sequences bounded by unconformities, named lower and upper pre-salt and salt. The lower pre-salt interval is characterised by wedge-shaped packages of reflections that thicken towards graben and half-graben-bounding normal faults. This stage ends with the development of an angular unconformity, inferred to form as a result of the onset of the oceanward migration of deformation. The upper pre-salt is typically defined by packages of subparallel and relatively continuous reflections that are broadly lenticular and thin towards fault-bound basement highs, but that locally contain packages that thicken against faults. The pre-salt to salt contact is defined by an erosional unconformity that is largely restricted to basement highs, and which is inferred to have formed due to base-level fall and uplift associated with local fault reactivation, resulting in the formation of channels of possible fluvial origin. Based on its geometries and seismic facies, we conclude that the lower pre-salt interval is syn-rifting and syn-tectonic, deposited during active continental extension and upper crustal faulting affecting the entire evolving margin, whereas the overlying upper pre-salt is syn-rifting and post-tectonic in the Campos Basin, deposited when extension and faulting had migrated seaward to the future location of the spreading centre. The results of our study support the arising notion that the syn-rift sequence does not only display syn-tectonic sedimentary packages, and thus the tripartite tectono-stratigraphic model for rift development is too simplistic and cannot be applied when assessing rifts in the context of the regional development of continental margins. [ABSTRACT FROM AUTHOR]

• We derived Earth observation (EO) data-based geological evidence layers for hydrocarbon prospecting. • EO based anomalies were synergized with geophysical, geochemical anomalies. • The study was carried out in the rift controlled sedimentary basin. • Hydrocarbon Prospect map was derived using weighted summation method. In the present study, we carried out a conjugate analysis of Landsat-8 Operational Land Imager (OLI), Sentinel-2B Multi-Spectral Instrument (MSI), Advanced Land Observation Satellite Phased Array L-band SAR (ALOS PALSAR), and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data over a study area of northern Cambay Basin to delineate prospective areas for hydrocarbon exploration. In this regard, we utilized feature-oriented principal component (PC) images of Landsat OLI data, PC images of Sentinel-2B visible and near-infrared (VNIR)-short-wave infrared (SWIR) bands, thresholded Cartosat-1 Digital Elevation Model (DEM), and polarization image composite of ALOS PALSAR data to delineate geomorphic and lineament features in the study area. Most of the geomorphic features, such as scroll plain, gullies, elevated pediment, circular drainage anomalies, etc., indicate localized structural uplift. Geomorphic anomalies and lineaments, essential for identifying structural controls of near-surface hydrocarbon accumulation, were identified using enhanced satellite data. Geophysical anomalies derived from gravity datasets supplemented the presence and down-depth continuity of geological structures. Spectral profiles of calcrete-bearing soil samples were used to identify calcrete-rich zones in the optical remote sensing image data as a proxy owing to field evidence of close association of calcrete-rich soils with known subsurface hydrocarbon accumulations. Sub-pixel mapping algorithm Constrained Energy Minimization (CEM) applied to SWIR bands of ASTER data was used to delineate surface proxies of near-surface hydrocarbon seepage. Isopach maps of shallowest reservoir formations (Mid-/ Late Eocene) were used as indicators of favorable near-surface hydrocarbon accumulation. Earth observation-based geomorphic, lineament, and spectral anomalies were integrated with supplementary datasets, such as reservoir isopach and absorbed gas anomalies, as controls using the weighted summation method for quantitative deduction of the hydrocarbon potential map of the study area. The weights for input variables or parameters (geomorphic, spectral, geochemical, etc.) were inferred based on spatial associations of these anomalous units/variables with the existing oil & gas well locations. The identified potential map is in broad synergy with the field observations on localized uplift, geo-botanical anomalies, and calcrete-rich zones within the extent of high & moderate hydrocarbon potential areas. [ABSTRACT FROM AUTHOR]

The Nukhul Formation has been a point of controversy until now due to a lack of index fossils, varied facies modifications, and different time gaps. As a result, the calcareous nannofossils of the exposed Miocene rocks at Wadi Baba, west-central Sinai have been studied quantitatively for the first time. An important sequence of calcareous nannofossil bioevents has been recorded in the Nukhul Formation, including the FOs of Discoaster druggii, Sphenolithus dissimilis, Helicosphaera ampilaperta, and Sphenolithus disbelemnos, which correspond to the Aquitanian age of upper NN1 and NN2 zones. The Nukhul Formation contains four intervals that reflect eutrophic conditions in the nearshore habitats with substantial nutrient input from the terrigenous influx, as shown by the dominance of cool-water taxa, Coccoliths pelagicus and Reticulofenestra minuta. The lithofacies, microfacies types, abundance, dominance, and diversity of nannofossil assemblages classified the studied interval into two depositional sequences with four system tracts. These tracts refer to fluctuations in relative sea level changes in response to the eustatic sea-level curve. [ABSTRACT FROM AUTHOR]

The Silves Group of the Lusitanian Basin in Portugal represents the initial infill of the continental rifting basins that formed during the breakup of northern Pangaea regions. Evaporites, especially halite, mark the transition from continental to marine settings and the beginning of the deposition in passive margin basins. This work presents the results of the palynostratigraphic and palynofacies analysis of two partial sections from the Pereiros Formation at the top of the Silves Group. The two sections are composed of sandstones, mudstones and dolostones interpreted as deposited in fluvial and lacustrine settings without apparent marine influence. The palynological content is diverse and wellpreserved, dating both sections to the early Hettangian (Lower Jurassic), indicated by the presence of spores Ischyosporites variegatus, Kraeuselisporites reissingeri, Porcellispora longdonensis and the pollen grains Perinopollenites elatoides and Pinuspollenites minimus. The palynological content of one of the sections (Lamas I) is noticeable by microforaminifera linings, suggesting evidence for a hitherto marine incursion at this age in the Silves Group stratigraphy. The beds that yielded the microforaminifera linings are interpreted as having been deposited in an estuarine-type setting, created by the first and short-lived marine transgressive event in the Lusitanian Basin during the early Hettangian. [ABSTRACT FROM AUTHOR]

The Lower Cretaceous (Barremian) Camarillas Formation in the Galve Sub‐basin of eastern Spain is an exceptionally muddy, synrift, aggradational then retrogradational paralic succession. Deposition within these arid, equatorial paralic systems was strongly controlled by crustal rifting of the Iberia plate linked to the geodynamic evolution of the Atlantic Ocean, the Bay of Biscay and the Tethys Ocean. Although synsedimentary extensional tectonics controlled thickness and facies distributions, the parasequence stacking patterns point to a superimposed high‐order allogenic control on the paralic succession. Field data and drone imagery are combined to document changes in sedimentology and three‐dimensional stratigraphic architecture of these deposits to interpret changes in depositional environments as this basin filled. Three evolutionary stages are identified: (i) tide‐dominated estuary; (ii) mixed‐energy estuary, with a well‐developed wave‐dominated barrier island system; and (iii) barrier island–tidal inlet suite. An exceptional record of back‐barrier‐island depositional interactions is preserved in this high‐subsidence, extensional‐basin setting, including deposition of washover fans, flood‐tidal deltas and ebb‐tidal deltas. Drone‐derived imagery facilitates three‐dimensional architectural characterization of these complex paralic deposits, including multi‐episodic tidal inlets, and correlation of basin scale stratigraphic markers. Spatio‐temporal interactions between climate change, sea‐level variations and rift‐related subsidence generated complex estuarine and barrier island geobodies. The general transgressive trend recorded in the Camarillas Formation correlates well with global eustatic sea‐level rise during the Barremian. [ABSTRACT FROM AUTHOR]

Climate cycles fundamentally control surface processes that affect the distribution of water and sediment, and their associated loads, across the Earth's surface. Here, we use a geodynamic model to examine how water loading can affect mantle melt generation in continental rift settings covered by deep lakes. Our modeling results suggest that lake level fluctuations can modulate the timing and rate of mantle melting. A rapid lake level drop of 800 m has the potential to increase mantle melt volumes by enhancing mantle upwelling beneath the rift, whereas a lake level rise can lead to a reduction of mantle melting. The volume of melt produced driven by lake level fluctuations is also dependent on crustal rheology, extension rate, mantle potential temperature, and lithosphere thickness. Our study identifies the importance of water loading for controlling rift processes, while also demonstrating critical links between changing climate, rift evolution and mantle melting. Plain Language Summary: The break‐up of continents produces subsidence and the formation of rift valleys and where the climate is favorable, rift lakes. Changes in effective moisture in response to climate changes drive water level fluctuations in rift lakes, and their associated loads. But our understanding of the interaction between hydroclimate changes and rift basin evolution remains limited. To address this, we employed a geodynamic model to explore how water loading can influence mantle melt production in continental rift environments. Our model suggests that lake level fluctuations can have a detectable effect on the timing and pace of mantle melting. A lake level drop can increase mantle melt volume by enhancing mantle upwelling underneath the rift, while a lake level rise can lead to a reduction in mantle melting. Additionally, the amount of melt produced by these fluctuations depends on factors such as crustal rheology, extension rate, thermal gradient, and lithosphere thickness. Our findings reveal the significance of water loading in governing rift processes and highlight the potential links between changing climate, rift evolution, and mantle melting. Key Points: Lake level drops of 800 m can enhance decompressive mantle meltingA case study for the Turkana Rift shows a correlation between lake level drops and enhanced volcanism over the last 4 MyrSensitivity of mantle melting to lake loading is controlled by extension rate, mantle potential temperature, and lithosphere thickness [ABSTRACT FROM AUTHOR]

The Kutch Rift Basin (KRB) is of great attention for its possible hydrocarbon reserve. In this context, geomorphologic and structural geologic studies of the onland basin area are crucial. Application of geomorphic indicators viz., compactness coefficient (Cc), lemniscate coefficient (k), form ratio (Rf), basin shape index (Bs), basin asymmetry factor (AF), hypsometric integral (HI), elongation ratio (Re) and circularity ratio (Rc) have been utilized to calculate the Index of Active Tectonics (IAT) for a part of KRB. Watersheds 5 (the Bhuj area), 9, 10, 11, 17, 18 and 20 belong to class 1 as per the IAT. This indicates that these watersheds are very highly tectonically active at present. Calculated valley floor width height ratio (Vf) and mountain front sinuosity (Smf) quantify the active valley incision in the Quaternary that uplifted the Bhuj area. This uplift was accompanied by a high-degree of drainage rejuvenation due to neotectonics and formation of a canyon in the Khari river. Paleostress analyses revealed NNE and NW-oriented extensions around Bhuj that can correspond to NW and NNE-trending normal fault planes, respectively.

Transfer zones are structural areas of faults interactions where fault motion or displacement can be transferred from one fault to another, regional strain maintains laterally constant. Transfer zones are widely developed in rift basins and have significance on hydrocarbon accumulation. In this review article, we attempt to summarize recent advances on the types, distance-displacement curves, evolutionary stages and controlling factors of transfer zones in rift basins and their effects on sedimentary systems, reservoir properties, trap formation and hydrocarbon migration. The formation of transfer zones is genetically related to the segmented growth of normal faults. Depending on the degree of interaction between these normal faults, transfer zones in rift basins could be divided into two types: soft-linked and hard-linked, which are further subdivided into transfer slope, oblique anticline, horst and transfer fault based on the combination patterns of normal faults. In general, the development of transfer zones experiences several stages including isolated normal faulting, transfer slope forming, complicating and breaking. During the interaction and growth of segmented normal faults, stress-strain and spatial array of faults, pre-existing basement structures, and mechanical conditions of rocks have a great influence on the location and development processes of transfer zones. A transfer zone is commonly considered as a pathway for conveying sediments from provenance to basin, and it hence exerts an essential control on the distribution of sandbodies. In addition, transfer zone is the area where stresses are concentrated, which facilitates the formation of various types of structural traps, and it is also a favorable conduit for hydrocarbon migration. Consequently, there exists great hydrocarbon potentials in transfer zones to which more attention should be given. [ABSTRACT FROM AUTHOR]

Based on seismic and drilling data in the study area, the geological structure and kinematic process of the Termit rift basin were studied using seismic profile interpretation and balanced restoration to find out the dynamic mechanism of the basin. (1) The geological structure of the Termit Basin is represented as a narrow rift basin, with development of series of structural styles in extensional, extensional strike-slip and compressional stress setting. On plane, it is narrow in the north and wide in the south, and transitions from graben to half-graben from north to south; it features a graben controlled by the boundary faults in the north and a fault-overlapped half-graben in the south. (2) Before the Cretaceous, a series of hidden faults developed in the West African rift system, which laid the foundation for the development location and distribution direction of the Termit Basin; during the Cretaceous to Paleogene periods, the basin experienced two phases of rifting in Early Cretaceous and Paleogene, which controlled the initial structure and current structural shape of the basin respectively; during the Neogene to Quaternary, the basin was subjected to weak transformation. (3) In the Precambrian, the Pan-African movement gave rise to a narrow and long weak zone within the African plate, which provided the pre-existing structural conditions for the formation of the Termit Basin. In the Early Cretaceous, affected by the South Atlantic rifting, the Pan African weak zone was reactivated, resulting in the first stage of rifting and the basic structural framework of the Termit Basin. In the Paleogene, affected by the subduction and convergence of the Neo-Tethys Ocean, the African-Arabian plate extended in near E-W trending, and the Termit Basin experienced the second stage of rifting. The oblique extension in this period caused intense structural differentiation, and the current structural pattern of alternate uplifts and depressions took shape gradually.

The slope zone of rift basin is close to the hydrocarbon generation center of deep depression zone, and is favorable area for oil and gas accumulation. Due to the heterogeneity of the development of fault and sedimentary system in slope zone, oil and gas accumulations often show obvious heterogeneity, and the degree and scale of oil and gas enrichment on the plane are different. The oil and gas accumulation of the second member of Funing Formation (E1f2) in the slope belt of Sanhe Sub-sag of Jinhu Sag of Subei Basin is characterized by rich in the south and poor in the north, and the hydrocarbon accumulation is controlled by multiple factors. Geochemical test and logging data interpretation showed that the southern part has better source conditions than the northern part in the study area. Three types of source-reservoir configurations were developed vertically: lower-sourced and middle-reserved, self-sourced and self-reserved, as well as upper-sourced and lower-reserved, among which the type of upper-sourced and lower-reserved is the most developed and has the most enriched oil and gas in the studied area. On the plane, there are three types of source-reservoir configurations: stacked source-reservoir type, source-reservoir adjacent type, and source-reservoir separated type. The northern part of the study area is dominated by the source-reservoir separation type, while the southern part is dominated by the stacked source-reservoir type and the source-reservoir adjacent type. The southern part of the study area has well-developed fault system, abundant provenance and sand bodies, while the northern part is far away from provenance and has underdeveloped sand bodies. It is concluded that the superior hydrocarbon source conditions, appropriate source-reservoir configurations and good transport system are the key factors controlling the enrichment of oil and gas in faulted basins.

This study clarified the sedimentary characteristics of hyperpycnal flow sediments, investigated the plane and vertical characteristics and the differences in hyperpycnal flow sedimentary systems from different provenances, and finally discussed the controlling factors of hyperpycnal flow in rift basins. The sedimentary characteristics of hyperpycnal flow in the Lower Shahejie Formation of the Qikou Sag, Bohai Bay Basin have been studied through the comprehensive analysis of drilling core, logging, seismic attribute, and grain data.The results show that there are three typical recognition features for the hyperpycnal flow deposits in the study area: ① The vertical sedimentary sequence is composed of a reverse grain grading in the lower part, a normal grain grading in the upper part and a relatively thick layer with no obvious change in grain size; ② The sediment is dominated by a gradual suspension. The types of cumulative probability curves include a complex multistage style, an upper arch style and a low slope two-stage style; ③ The lithofacies is characterized by erosional filling deposition and various bedding structures with the development of maroon argillaceous layers, maroon gravels, abundant plant debris and carbonaceous debris. The channelized hyperpycnal flow sediments have multiple sources. The most significant source is the Gegu source, which is characterized by a long-distance transportation path, multiple flower bodies and widespread deposits along the transportation path.Two types of sedimentary models are established in this study, and the controlling factors of hyperpycnal flow include paleogeomorphology, paleoprovenance and paleoclimate. Considering that hyperpycnal flow widely exists in rift lacustrine basins with its channel sandstone bodies being good reservoir properties, our study suggests that hyperpycnal flow is a breakthrough point for oil and gas exploration in continental rift lacustrine basins.

The Gudian Rift is a favorable area for deep natural gas exploration in the southern Songliao Basin, and it also records rich information on basin evolution and Mesozoic-Cenozoic plate movements in eastern China.By using the well and high-resolution 3D seismic data, combined with regional tectonics, the geological structure and tectonic evolution of the Gudian Rift were investigated.The results show that the Gudian Rift can be vertically divided into basement, lower, middle and upper structure layers.Due to the subduction of the Pacific Plate beneath to the East Asian Plate and the changes in the regional tectonic stress field since the Late Mesozoic, the Gudian Rift experienced syn-rift, transition, post rift and tectonic inversion periods.The Gudian fault was initially formed from six fault segments in syn rift period(depositional period of the Huoshiling and Shahezi Formations) and the isolated fault segments with different strikes then grew and connected to a unified boundary fault in the late rifting stage(depositional period of the Yingcheng Formation).Afterwards, extensive and intense transtensional activities occurred during transition(depositional period of the Denglouku and Quantou Formations) and depression periods(depositional period of the Qingshankou, Yaojia and Nenjiang Formations), and strong inversion and segmental thrust activities occurred during inversion period(end of the depositional period of the Nenjiang Formation), respectively.This study provides references for the investigation of tectonic activity and evolution in the Songliao Basin and eastern China, and further guides oil and gas exploration.

Several international oil companies had conducted petroleum exploration, but failed to make any commercially viable discoveries in the Doseo Basin for over 30 years. In this article, an integrated analysis, based on the latest seismic and drilling data combined with exploration practice and tectonic, sedimentary as well as petroleum-geological characteristics of the basin, has been conducted with the aim to disclose the key factors of hydrocarbon accumulation and enrichment and then to find the potential petroleum plays. The Doseo Basin in Chad is a Meso-Cenozoic lacustrine rift basin developed on the Precambrian crystalline basement in the Central African Shear Zone. It is a half graben rift controlled by the strike-slip fault at the northern boundary, and can be divided into two sub-basins, an uplift and a slope. The basin experienced two rifting periods in the Cretaceous and was strongly inverted with the erosion thickness of 800–1000 m during the Eocene, and then entered the depression and extinction period. Structurally, a large number of normal faults and strike-slip faults are identified in the basin, and the boundary faults are inverted faults with normal at first. The main structural styles include inverted anticlines, fault noses, complex fault-blocks and flower structures. The Lower Cretaceous is the main sedimentary strata, which are divided into the Mangara Group, Kedeni, Doba and Koumra Formations from bottom to up. Two transgressive-regressive cycles developed in the Lower Cretaceous indicates with mainly lacustrine, fluvial, delta, braided-delta, fan-delta sandstone and mudstone. The effective source rock in the basin is the deep-lacustrine mudstone of the Lower Cretaceous containing the type I and type II1 organic matters. Furthermore, Inverted anticlines and fault-complicated blocks comprise the main trap types and the Kedeni Uplift is the most favorable play, followed by the Northern Steep Slope and Southern Gentle Slope. Lateral sealing capacity of faults controls the hydrocarbon abundance.

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Abstract Side‐scan sonar and Compressed High Intensity Radar Pulse mapping of Great Salt Lake, Utah, linked to reprocessing of acoustic data from bathymetric surveys, has enabled the distribution of microbial bioherms to be assessed. Bioherms occupy an estimated area >700 km2 in the south arm and >300 km2 in the north arm. Distributions vary from statistically dispersed to clustered, and in this latter case, are predominantly located on metre‐scale, fault‐controlled topographic highs, with sediment infilling intervening lows between adjacent offsets. Individual bioherms are circular to oblate and range from centimetres to over 2 m in diameter. In some areas, bioherm heights were measured at more than 1.5 m above adjacent substrate. Sublittoral bioherms are made of aragonite, calcite and minor dolomite precipitated due to physico‐chemical, biologically induced and influenced carbonate mineralization processes in association with microbial mats. Bioherm fabrics vary at the millimetre to centimetre‐scale and consist of leiolitic and clotted peloidal micrite‐grade carbonate, sinuous threads of spherulitic fibrous aragonite crystals, laminated micrite boundstone and internal carbonate mud sediment with peloids and ooids. The identification of factors that influence microbial bioherm occurrence and spatial distribution in Great Salt Lake is limited to a set of collinear physical, chemical and biological variables that are confined to a localised closed system, such as salinity, water depth, wave energy, stable substrate and sediment accumulation. Anthropogenic modifications to Great Salt Lake resulting in increased salinity have exceeded the salinity range in which bioherm‐mediating microbial communities can survive, effectively defining an upper limit of salinity for bioherm microbial community viability. The better understanding of the distribution of microbial bioherms has significant implications for managing and protecting the lake ecosystem and may provide insights into the physical and chemical controls that existed during the formation of fossil microbialites in deep time.

The Campos and Santos Basins have been a focus of subsurface studies since the discovery in 2006 of large accumulations of hydrocarbons in the Early Cretaceous rift and post‐rift strata below Aptian evaporites. In this study, regional 2D seismic lines, a 3D seismic survey and well data were interpreted to reconstruct the tectono‐stratigraphic evolution of the rift and post‐rift stages in the northern sector of the Campos Basin. Detailed 3D seismic interpretation and geological modelling were used to subdivide the pre‐salt sedimentary record. This revealed a diachronous strain distribution along the Guriri Fault System (GFS), a roughly NE‐SW striking fault‐bounded horst that was a focus of rift‐related deformation. The syn‐rift succession is interpreted to be the product of two episodes of rifting (RP1 and RP2) with contrasting fault activity patterns and lithostratigraphy. Volcaniclastics and coarse siliciclastics of RP1 were deposited under WNW‐ESE transtension that formed discontinuous half‐grabens followed by extensive erosion and tectonic inversion. Structurally controlled bioclastic rudstones and hybrid deposits characterize RP2 and were deposited in elongated half‐grabens that delimit the GFS horst, which developed under an NW‐SE extension. Deposition under increasingly less tectonically active transitional and post‐rift stages dominated by thermal subsidence gradually led to the healing of the rift‐related structural relief. Selective reactivation of rift faults testifies active tectonic inversion through compression from immediate post‐rift throughout evaporite deposition. These interpretations are put into the context of recent geochronological data of onshore dyke emplacement and the new age constraints for the end of deposition of the pre‐salt sequence. Therefore, we propose an earlier onset on rifting in the Campos Basin, at the Berriasian. [ABSTRACT FROM AUTHOR]

An evaluation system of hydrocarbon-bearing availability of fault traps was established based on the comprehensive analysis of fault segment growth history, fine reservoir anatomy and geochemistry tracing, with the Qikou sag in the Bohai Bay Basin as target area. The displacement/separation transform and displacement gradient method were used to prove the interpretation reliability of fault traps. The method of maximum throw subtraction was used to recover the history of fault growth and determine the availability of the forming period of fault traps. Based on the quantitative relationship between shale gouge ratio and cross-fault pressure difference of known reservoirs in southern Qikou sag, the critical shale gouge ratio of fault lateral sealing was calculated at 20%, and the quantitative evaluation chart based on the relationship of “fault throw–sand-formation ratio and hydrocarbon column height” was constructed. Based on the results of reservoir fine anatomy and quantitative fluorescence tracing test shale smear factor method is suitable for evaluating the vertical sealing of faults in the caprock of the middle submember of first member of Paleogene Shahejie Formation, and the shale smear factor critical value is 3.5. The juxtaposition thickness method is suitable for evaluating vertical sealing of faults in the caprock of the second member of Paleogene Dongying Formation, and the critical juxtaposition thickness of fault is 70–80 m. By combining four factors, the availability of fault trap interpretation, the availability of the forming period of fault trap, the availability of fault lateral sealing and the availability of fault vertical sealing, the comprehensive evaluation chart on hydrocarbon-bearing availability of fault traps in Qikou sag has been established, which provides a reasonable basis for risk assessment of fault traps.

The evolution of normal fault arrays during rift extension reflects paleo-plate boundary conditions and lithospheric rheology, while controlling seismic hazard and the distribution of basin-hosted resources. Yet, constraining their spatiotemporal development is challenging, particularly where geophysical and subsurface data are absent. Here, we test footwall exhumation modelling using thermochronology as a means of elucidating 4D normal fault array evolution, using the Miocene Central Basin of the Malawi Rift as a natural laboratory. Along-strike trends in exhumational cooling recorded by vertical transects of apatite fission-track and (U–Th)/He data from the basin-bounding Usisya fault scarp reveal a diachronous footwall uplift history that closely reflects 4D trends in hangingwall subsidence recorded by previously published seismic and well data. Initially, pronounced footwall exhumation is restricted to the centres of a series of four isolated normal faults, mirroring the distribution of early syn-rift depocentres. The later onset of footwall exhumation in the intervening areas marks subsequent fault segment propagation and linkage as they formed the through-going Usisya fault system. Elsewhere, cumulative exhumation recorded in the Usisya footwall remains low, coinciding with more significant intra-basinal faulting. This study shows that footwall exhumation modelling constrained by thermochronologic data can reveal the spatiotemporal evolution and strain partitioning within normal fault arrays. • Thermochronology transects along the Usisya fault scarp record footwall exhumation. • Usisya fault evolution is reflected in basin stratigraphy revealed by seismic data. • Malawi rift related cooling along Usisya commenced in the middle Miocene. • Footwall exhumation modelling reveals complex 4D fault exhumation and linkage. [ABSTRACT FROM AUTHOR]

Although volcanism is an important process in the evolution of rift basins, current tectono‐sedimentary models largely neglect its impact on sediment supply, transport pathways, and depositional systems. In this paper, we integrate core, well logs, and 3D seismic data from the Palaeogene‐Neogene Shaleitian (SLT) uplift and surrounding sub‐basins, Bohai Bay Basin, China, to investigate the sedimentology and geomorphology of a volcanic rift basin. Results of this study show that the spatial distribution of extrusive centres was strongly controlled by basement‐involved intra‐basin normal faults. During the early part of the syn‐rift stage, the SLT uplift supplied sediments to transverse fan deltas and braided‐river deltas that fringed the adjacent syn‐rift depocentres. Volcanic deposits mainly occurred as relatively thin lava flow and pyroclastic facies that partially filled fault‐controlled topographic lows, reducing topographic rugosity, and enhanced breaching of basement highs between syn‐rift depocentres. Integration of drainage to the syn‐rift depocentres and development of through‐flowing axial depositional systems was enhanced. During the later part of syn‐rift and in early post‐rift stages, the SLT uplift was progressively inundated, reducing sediment supply to the fringing transverse depositional systems. In contrast, axial braided‐river deltas became the main depositional systems, sourced by large hinterland drainage from the Yanshan fold‐belt to the northwest. Volcanism in the late syn‐rift and early post‐rift occurs as thick lava flow and pyroclastic facies that infill rift topographic lows and locally blocked axial fluvial systems creating isolated lakes. Within hanging wall depocentres, volcanic topographic highs split and diverted axial fluvial and deltaic systems. Furthermore, volcanism supplied large volumes of volcanic sediment to the rift resulting in increased sedimentation rates, and the development of unstable subaerial and subaqueous slopes and deposits, increasing the occurrence of landslides. Based on the observations of this study we update tectono‐sedimentary models for rift basins to include volcanism. [ABSTRACT FROM AUTHOR]

Mesozoic ferns from Mexico have been the subject of serious academic endeavours since the beginning of the 20th Century, to understand these plants at the time of their peak diversity. Most findings have been made in a set of Middle Jurassic Basins of the Mixtec Terrain in the Oaxaca State. However, fossil ferns are scarce in other assemblages, so further identification of this group has been infrequent. Here we describe six new and recently collected fossil plants from the Middle Jurassic Otlaltepec Formation, Puebla. Based on their fertile and vegetative fronds, we propose the new genus Paralophosoria Morales-Toledo, Mendoza-Ruiz & Cevallos-Ferriz, gen. nov. in the Dicksoniaceae, represented by Paralophosoria jurassica, Morales-Toledo, Mendoza-Ruiz & Cevallos-Ferriz, sp. nov., and identify the following genera: cf. Aspidistes, Sphenopteris, Spiropteris. A fern with uncertain affinities was also described. This work contributes to the understanding of fern diversity in low latitudes during the Middle Jurassic in Mexico. [ABSTRACT FROM AUTHOR]

Continental rifts have a significant role in supercontinent breakup and the development of sedimentary basins. The Australian Adelaide Superbasin is one of the largest and best-preserved rift systems that initiated during the breakup of Rodinia, yet substantial challenges still hinder our understanding of its early evolution and place within the Rodinian supercontinent. In the past decade, our understanding of rift and passive margin development, mantle plumes and their role in tectonics, geodynamics of supercontinent breakup, and sequence stratigraphy in tectonic settings has advanced significantly. However, literature on the early evolution of the Adelaide Superbasin has not been updated to reflect these advancements. Using new detrital zircon age data for provenance, combined with existing literature, we examine the earliest tectonic evolution of the Adelaide Superbasin in the context of our modern understanding of rift system development. A new maximum depositional age of 893 ± 9 Ma from the lowermost stratigraphic unit provides a revised limit on the initiation of sedimentation and rifting within the basin. Our model suggests that the basin evolved through an initial pulse of extension exploiting pre-existing crustal weakness to form half-grabens. Tectonic quiescence and stable subsidence followed, with deposition of a sourceward-shifting facies tract. Emplacement and extrusion of the Willouran Large Igneous Province occurred at c. 830 Ma, initiating a new phase of rifting. This rift renewal led to widespread extension and subsidence with the deposition of the Curdimurka Subgroup, which constitutes the main cyclic rift sequence in the Adelaide Superbasin. Our model suggests that the Adelaide Superbasin formed through rift propagation to an apparent triple junction, rather than apical extension outward from this point. In addition, we provide evidence suggesting a late Mesoproterozoic zircon source to the east of the basin, and show that the lowermost stratigraphy of the Centralian Superbasin, which is thought to be deposited coevally, had different primary detrital sources. [ABSTRACT FROM AUTHOR]

Abstract The architecture of lacustrine systems is the result of the complex interaction between tectonics, climate and environmental parameters, and constitute the main forcing parameters on the lake dynamics. Field analogue studies have been performed to better assess such interactions, and their impact on the facies distribution and the stratigraphic architecture of lacustrine systems. The Yacoraite Formation (Late Cretaceous/Early Palaeocene), deposited during the sag phase of the Salta rift basin in Argentina, is exposed in world‐class outcrops that allowed the dynamics of this lacustrine system to be studied through facies analysis and stratigraphic evolution. On the scale of the Alemania‐Metán‐El Rey Basin, the Yacoraite Formation is organized with a siliciclastic‐dominated margin to the west, and a carbonate‐dominated margin to the east. The Yacoraite can be subdivided into four main ‘mid‐term’ sequences and further subdivided into ‘short‐term’ sequences recording high frequency climate fluctuations. Furthermore, the depositional profiles and identified system tracts have been grouped into two end‐members at basin scale: (a) a balanced ‘perennial’ depositional system for the lower part of the Yacoraite Formation and (b) a highly alternating ‘ephemeral’ depositional system for the upper part of the Yacoraite Formation. The transition from a perennial system to an ephemeral system indicates a change in the sedimentary dynamics of the basin, which was probably linked with the Cretaceous/Tertiary boundary that induced a temporary shutdown of carbonate production and an increase in siliciclastic supply.

The Canterbury Basin in southeastern Zealandia was initiated during the late Albian (ca. 105 Ma) as a rift system, prior to the onset of seafloor spreading between Zealandia and eastern Gondwana at ca. 85 Ma. Basin‐fill architecture and sediment types have been determined from interpretation of 2D and 3D seismic‐reflection lines tied to five wells and compared to outcrop data from the literature. These data show that Cretaceous syn‐rift basin‐fill architecture was controlled by normal faulting, which produced basin and range topography that persisted for more that ca. 30 Myr after the cessation of faulting. Initial sedimentation was dominated by short drainage systems sourced from within the basin to produce alluvial fans along fault scarps, which inter‐fingered with axial‐flowing braided river conglomerates, coal measures and mudstone‐rich lake deposits in more central portions of the basins. Marine incursion of the basin from the east commenced during rifting and onset of Gondwana breakup, with maximum water depths achieved in the Oligocene. Post‐rifting, detrital sediments were mainly sourced locally from structural highs and augmented by pelagic sedimentation, which collectively draped and eventually buried most of the earlier‐formed horsts by the Early Eocene. The temporal persistence of basin and range topography reflected the low rates of erosion of horst blocks compared to the rates of fault displacement. The lack of substantial sediment input from outside of the rift basin was a key factor in the under‐filling of the Canterbury Basin. This research emphasises the key role played by sediment supply in rift basin filling. Despite an abundance of active faulting at initiation, some rift basins may fill slowly over tens of million years after rift cessation. [ABSTRACT FROM AUTHOR]