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Basin hydrology and subcrop are key controls on carbonate sedimentation in continental basins. Hydrologically sensitive carbonates can record groundwater fluctuations within an aquifer in deep time. Late Jurassic extension, footwall uplift, erosion and karstification of marine Jurassic carbonates in the western Cameros Basin (Spain) saw deposition of ?Upper Kimmeridgian‐Tithonian syntectonic alluvial fan deposits (Señora de Brezales Formation). Biogenic laminar calcretes and phreatophytic rhizocretions record roots exploiting capillary fringe groundwater. Progressive infill of rift topography and footwall erosion lowered sedimentary gradients and clastic supply during deposition of the ?Tithonian–Berriasian Rupelo Formation. Distal alluvial marls (Las Viñas Member) contain charophytes, with 2 m thick carbonate lenses at the top reflecting intermittent rise of groundwater in ponds on the basin floor. Stacked palustrine limestones with rare charophytes and laminar calcretes (Ladera Member) record overstep of seasonal carbonate wetlands onto basin margins and footwall highs with intense pedogenetic modification during lengthy seasonal exposure. Overlying Berriasian charophyte‐ostracod wackestones, displaying microkarst cavities and interbedded intraclastic conglomerates, with vivianite sauropod bones, footprints and polygonal desiccation cracks at the top (Mambrillas de Lara Member) record open lacustrine conditions with limited subaerial exposure and high water tables. Desiccation‐cracked limestones and marls with correlatable evaporite horizons (Rio Cabrera Member) contain marginal marine foraminifera and dasycladaceae at the top. Lagoonal conditions reflected transgression to seaward and intermittent marine connection via the Basco‐Cantabrian Basin. The distribution and thicknesses of hydrologically sensitive carbonates reflected onlap onto a faulted and karstified marine Jurassic carbonate pediment and the subtle influence on hydroperiod of fault (and potentially localised Triassic salt) controlled differential subsidence and transgressive groundwater rise. Hydrological facies evolution reflects progressive basin infilling and eustasy beyond. Transitions in this continental succession from clastic to carbonate facies and from closed to open hydrology record hydrological change over time rather than contemporaneous deposition under Walther's Law. Late Jurassic extension, footwall uplift, erosion and karstification of marine Jurassic carbonates in the western Cameros Basin (Spain) resulted in the deposition of ?Upper Kimmeridgian‐Tithonian syntectonic alluvial fan deposits and a series of ?Tithonian to Berriasian distal alluvial marls, palustrine, lacustrine and finally lagoonal carbonates. The distribution and thicknesses of hydrologically sensitive carbonates in this succession resulted from onlap onto a faulted and karstified marine Jurassic carbonate pediment and the subtle influence on hydroperiod of tectonically‐ (and potentially localised Triassic salt‐) controlled differential subsidence and transgressive groundwater rise.

Lakes are sensitive indicators of the balance between accommodation and sediment supply, recording high‐resolution changes in palaeoenvironmental conditions. Long‐lived rift lake basins, however, are predominantly controlled by episodic accommodation changes and pronounced basinward facies shifts, complicating the generalisation of tectonic and climatic controls on rift lake successions. This study proposes a sequence framework and depositional pattern for asymmetric half‐grabens in syn‐rift lake basins by characterising the lacustrine fan‐delta deposits of the Lower Cretaceous Shahezi Formation in the Songliao Basin. Detailed sedimentologic and petrographic analyses identified 24 lithofacies categorised into seven facies associations. A sequence stratigraphic framework was constructed to outline the tectono‐stratigraphic evolution during the syn‐rift phase. The results indicate that the syn‐rift Lishu palaeo‐lake is characterised by its relatively small size, steep slopes, poorly developed and siliciclastic‐dominant shoreline strata and significant input of allochthonous biodetritus. The syn‐rift deposits show a distinct threefold conglomerate–sandstone–mudstone motif, with a complete cycle comprising a prolonged retrogradational phase (LST and TST) and a brief progradational phase (HST). Basin‐bounding faults accelerated hinterland erosion and increased sediment feeder system slopes by rotating hangingwall blocks; consequently, rapid sediment transport and localised gravitational collapse caused the common occurrence of soft‐sediment deformation structures and sublacustrine fan conglomerates. The substantial increase in accommodation space, resulting from fault‐generated subsidence, triggered lake expansion and further contributed to the development of transgressive system tracts and continuous mudstone deposition. These mudstones, rich in terrigenous organic matter and allochthonous fossils, correlate with carbonaceous mudstones, coals and conglomeratic sandstones in proximal overfilled sections, indicating a dynamic interplay between fan delta progradation and Lake Shoreline transgressions. This study proposes a depositional model within a sequence stratigraphic framework for non‐marine sediment accumulation in asymmetric half‐grabens bounded by active faults. The findings offer insights that complement existing models developed for marine rift systems. A consistent model for the sequence framework and depositional pattern of asymmetric half‐grabens in syn‐rift lake basins bounded by active faults has been established, complementing existing models for marine rift successions. Syn‐rift lake basins are characterised by relatively small dimensions, steep slopes, poorly developed shoreline strata dominated by siliciclastics and significant input of allochthonous biogenic detritus.

Regional 2D multichannel seismic, borehole, dredge and outcrop data, together with burial models for strata in southwest Iberia, are used to investigate the tectono‐stratigraphic signature of multiphased rifting on divergent margins. Our burial model reveals that Mesozoic extension occurred during three main phases, each comprising distinct subsidence pulses separated by short‐lived periods of crustal uplift. The importance of the three phases varies across discrete sectors of the margin, each one revealing similar depositional architectures and associated tectonic systems tracts: 1) the Rift Initiation phase, characterized by incipient subsidence and overall aggradation/progradation over a basal unconformity, 2) the Rift Climax phase, which marks maxima of tectonic subsidence and is characterized by retrogradation‐progradation, and 3) the Late Rift phase, recording the progradational infill of the basin and the effects of eustasy. The Rift Initiation systems tracts comprise Sinemurian and late Callovian‐early Oxfordian strata. Marine units in the Pliensbachian and Late Oxfordian‐Kimmeridgian represent the Rift Climax phase, a period marked by the development of Maximum Flooding Surfaces. Late Rift deposits were identified in the Rhaetian‐Hettangian, Toarcian‐Bathonian and Kimmeridgian‐Berriasian. The results of this work are important to the economic exploration of deep‐offshore rift basins, as they reveal that sequence stratigraphy can be used to predict sedimentary facies distribution in more distal segments of such basins. Significantly, this work recognizes that multiple tectonic‐stratigraphic (rift) cycles can occur on deep‐offshore rift basins, from the onset of rift‐related extension until continental break‐up, a character that contrast to what is known from deep‐sea drilling data from the distal margin of Northwest Iberia. Key Points Sequence stratigraphy analysis of multiphased rift successions Tectono‐stratigraphic evolution of the southwest Iberian margin Evolution of the triple point of North Atlantic, Tethys, and Central Atlantic

Central and southern Mexico represents a strategic place to understand the dynamics of Pangaea break-up and its influences on the evolution of the Pacific margin of North America. Lower–Middle Jurassic volcano-sedimentary successions, and scarce magmatic rocks, crop out discontinuously across this region and have been interpreted either as a vestige of a continental arc or as several deposits of syn-rift magmatism. At present, their origin is controversial. Available geochemical data on these igneous rocks suggest that they represent almost pure crustal melts produced in a rift environment rather than in an arc. In fact, the studied rocks exhibit the high silica contents and moderate to strong peraluminous character typical of sediment melts. The enriched isotopic composition (high 86Sr/87Sr and low 143Nd/144Nd) and the age distributions of inherited zircon grains readily identify the widespread Upper Triassic metasedimentary sequences presently exposed in southwestern and central Mexico as the most likely crustal source of these Jurassic igneous rocks. Accordingly, we argue that these Early–Middle Jurassic magmas originated in a syn-rift igneous province associated with extensional-driven crustal attenuation in the context of Pangaea fragmentation. Our findings also constrain post-Pangaea subduction initiation to be younger than Middle Jurassic time in central and southern Mexico.

Assimilation and prolonged suspension of crust-derived sulfide liquid in komatiites are essential to form Ni-rich mineralisation. Evaluating the spatial relationship between komatiite-hosted Ni mineralisation and crustal S sources may thus provide insights into mechanisms of transport, metal enrichment and deposition of assimilated sulfide liquid. This study applied facies analysis and S isotopes to sulfides in Ni-mineralised komatiites and stratigraphically underlying bimodal volcanic-volcaniclastic and sedimentary rocks, which formed during rifting in the Agnew-Wiluna Greenstone Belt, Western Australia. The results revealed a lateral variation from rift-distal sedimentary sulfides, through sulfidic BIF, to rift-proximal VMS-style sulfides, the latter of which was predominantly assimilated by komatiites. Both crustal and komatiite-hosted sulfides were overprinted by granite-related skarn alteration during later basin inversion. Spatial S isotopes correlation revealed that Ni mineralisation in komatiites predominantly formed < 5 km from their crustal S sources, excluding long lateral transport as the main metal enrichment mechanism. Rather, metal enrichment likely happened through multiple cycles of sulfide entrapment and entrainment in lava flow vortices that formed in the wake of topographic steps represented by syn-rift faults. These faults were the main loci for pre-existing crustal weaknesses, hydrothermal fluid circulation, and VMS-style sulfide deposition, which were subsequently utilised by komatiites for enhanced thermo-mechanical erosion and crustal sulfide assimilation. This study shows that proximity to the syn-rift faults was the dominant control on the formation of komatiite-hosted Ni–sulfide mineralisation, regardless of substrate lithology. The S isotope signatures of crustal sulfides may be used as a proxy to identify syn-rift faults in highly deformed terranes.

Deep saline aquifers in the eastern part of Drava Basin were screened for potential storage sites. The input dataset included three seismic volumes, a rather extensive set of old seismic sections and 71 wells. Out of all identified potential storage objects, only two sites were found to be situated in the favorable geological settings, meaning that the inspected wells drilled through structural traps had a seal at least 20 m thick which was intersected by only a few faults with rather limited displacement. Many more closed structures in the area were tested by exploration wells, but in all other wells, various problems were encountered, including inadequate reservoir properties, inadequate seal or inadequate depth of the identified trap. Analysis was highly affected by the insufficient quality and spatial distribution of the seismic input data, as well as in places with insufficient quality of input well datasets. An initial characterization of identified storage sites was performed, and their attributes were compared, with potential storage object B recognized as the one that should be further developed. However, given the depth and increased geothermal gradient of the potential storage object B, it is possible that it will be developed as a geothermal reservoir, and this brings forward the problem of concurrent subsurface use.

Models that aim to capture the interactions between sediment supply, base level and tectonism recorded in fan delta successions in rift basins have not considered the stratigraphic archive preserved in interfan areas; yet interfan stratigraphy can provide a complementary record to the fan delta axes. The exhumed Early–Middle Pleistocene Kerinitis and Selinous fan deltas, in the hangingwall of the Pyrgaki–Mamoussia (P‐M) Fault, Corinth Rift, Greece, offer an ideal laboratory for the assessment of interfan architecture. Furthermore, using the geometry of adjacent present‐day fan deltas, interfans are classified into three end‐members. The classification is based on their lateral separation, which determines the degree of interfingering of topset, foreset and bottomset deposits. Qualitative (facies, stratal geometries, nature of key surfaces) and quantitative (stratigraphic thickness, bedding dip, palaeocurrents, breakpoint trajectories) data were collected in the field and from unmanned aerial vehicle photogrammetry‐based 3D outcrop models of the exhumed fan delta successions. The ancient Kerinitis–Selinous interfan architectures record: (a) initial westward progradation of the Kerinitis fan delta into the interfan area (Phase 1), (b) subsequent progradation of the Selinous fan delta into the interfan area and asymmetric growth of both fan deltas eastward (Phase 2), (c) stratal interfingering of foresets from both systems (Phase 3), and (d) relative base‐level fall, erosion and reworking of sediments into the interfan area (Phases 4 and 5). The Kerinitis–Selinous interfan evolution is linked to initial net subsidence of the P‐M Fault (Phases 1–3) and subsequent net uplift (Phases 4 and 5) resulting from a northward shift in fault activity. The interfan area provides a more complete stratigraphic record than the proximal axial areas of the fan deltas of the early stages of basin uplift, through higher preservation potential and protracted submergence. Therefore, for the most comprehensive insight into basin evolution, interfan analysis should be undertaken in concert with analysis of the fan delta axes.

A proper investigation of geomechanical properties of reservoir sediments allows accurate prediction of both magnitude and direction of different stress regimes. These are crucial for hydrocarbon production and development particularly in deformed and structurally controlled petroliferous basins. The rift basins in the north Western Desert (NWD) provide analogues for these structurally controlled prolific regions, where the syn-rift Jurassic sedimentary successions host prolific reservoir targets. However, a detailed assessment of the geomechanical behavior of the Jurassic reservoirs has never been investigated. Thus, the present study utilizes wireline log data to determine the geomechanical properties of the syn-rift Jurassic facies of the Khatatba Formation in Shushan Basin in the NWD. Mechanical earth model was constructed and formation microimager logs (FMI) were interpreted for to investigate the geomechanical behavior and wellbore stability of the studied deformed facies. The stress direction was determined from FMI by identifying drilling-induced fractures, breakout zones and formation fractures. Resistive, conductive and partially conductive fractures are oriented in NE–SW, ESE–WSW, NW–SE, NE–SW and SW–NE directions coinciding with the Jurassic syn-rift structures. The ENE–WSW direction of breakout and minimum horizontal stress (SH min ) are the same as that of the primary fault in the study region contrasting with the NNW–SSE direction of maximum horizontal stress (SH max ) and induced fractures. The present study highlights the significance of integrating wireline logging results in interpreting the critical and non-critical stress orientations which are necessary for optimal production plans in structurally controlled prolific basins around the globe.

The Eocene fourth member of the Shahejie formation (Es4x) in the Bonan Depression, Bohai Bay Basin, records syn-rift sedimentation under alternating arid and humid climates. It provides insight into how orbital-scale climatic fluctuations influenced tectonics, facies patterns, and reservoir distribution. This study integrates 406 m of core data, 92 thin sections, 450 km2 of 3D seismic data, and multiple geochemical proxies, leading to the recognition of five facies associations (LFA): (1) alluvial fans, (2) braided rivers, (3) floodplain mudstones, (4) fan deltas, and (5) saline lacustrine evaporites. Three major depositional cycles are defined within the Es4x. Seismic reflections, well-log patterns, and thickness trends suggest that these cycles represent fourth-order lake-level fluctuations (0.8–1.1 Myr) rather than short 21-kyr precession rhythms. This implies long-term climate and tectonic modulation, likely linked to eccentricity-scale monsoon variability. Hyperarid phases are marked by Sr/Ba > 4, δ18O > +4‰, and thick evaporite accumulations. In contrast, Sr/Ba < 1 and δ18O < −8‰ reflect humid conditions with larger lakes and enhanced fluvial input. During wet periods, rivers produced sand bodies nearly 40 times thicker than in dry intervals. Reservoir quality is highest in braided-river sandstones (LFA 2) with 12%–19% porosity, preserved by chlorite coatings that limit quartz cement. Fan-delta sands (LFA 4) have <8% porosity due to calcite cementation, though fractures (10–50 mm) improve permeability. Floodplain mudstones (LFA 3) and evaporites (LFA 5) act as seals. This work presents a predictive depositional and reservoir model for arid–humid rift systems and highlights braided-river targets as promising exploration zones in climate-sensitive basins worldwide.

Fluid flow prediction in clastic heterogeneous reservoirs is a universal issue, especially when diagenetic development supplants structural and depositional controls. We consider this issue in the Middle Miocene Belayim Formation of the Gulf of Suez, a principal syn-rift reservoir where extreme, diagenetically induced pore system heterogeneity thwarts production. Although fault compartmentalization is understood as creating first-order traps, sub-seismic diagenetic controls on permeability anisotropy and reservoir within these traps are not restricted. This study uses a comprehensive set of petrophysical logs (ray gamma, resistivity, density, neutrons, sonic) of four key wells in the western field of Tawila (Tw-1, Tw-3, TW-4, TN-1). We apply an integrated workflow that explicitly derives permeability from petrophysical logs and populates it within a seismically defined structural framework. This study assesses diagenetic controls over reservoir permeability and fluid flow. It has the following primary objectives: (1) to characterize complicated diagenetic assemblage utilizing sophisticated petrophysical crossplots; (2) to quantify the role of shale distribution morphologies in affecting porosity effectiveness utilizing the Thomas–Stieber model; (3) to define hydraulic flow units (HFUs) based on pore throat geometry; and (4) to synthesize these observations within a predictive 3D reservoir model. This multiparadigm methodology, involving M-N crossplotting, Thomas–Stieber modeling, and saturation analysis, deconstructs Tawila West field reservoir complexity. Diagenesis that has the potential to destroy or create reservoir quality, namely the general occlusion of pore throats by dispersed, authigenic clays (e.g., illite) and anhydrite cement filling pores, is discovered to be the dominant control of fluid flow, defining seven unique hydraulic flow units (HFUs) bisecting the individual stratigraphic units. We show that reservoir units with comparable depositional porosity display order-of-magnitude permeability variation (e.g., >100 mD versus <1 mD) because of this diagenetic alteration, primarily via pore throat clogging resulting from widespread authigenic illite and pore occupation anhydrite cement, as quantitatively exemplified by our HFU characterization. A 3D model depicts a definitive NW-SE trend towards greater shale volume and degrading reservoir quality, explaining mysterious dry holes on structurally valid highs. Critically, these diagenetic superimpressions can replace the influence of structural geometry on reservoir performance. Therefore, we determine that a paradigm shift from a highly structured control model to an integrated petrophysical and mineralogical approach is needed. Sweet spot prediction relies upon predicting diagenetic facies distribution as a control over permeability anisotropy.