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A summary of the Jurassic‐Cretaceous rift to breakup tectonostratigraphy of the onshore Sverdrup Basin is correlated to the offshore Amerasia Basin in order to reconstruct a tectonic setting for the High Arctic Large Igneous Province (HALIP). The rift climax from the Canadian rifted margin is correlated with hyper‐extension of the continent‐ocean‐transition zone. Hyper‐extension of the continental lithosphere can accommodate plate motions of Arctic Alaska‐Chukotka away from the Canadian Arctic Islands and Lomonosov Ridge between ∼155 Ma and 135–133 Ma. After lithospheric breakup at ∼135–133 Ma, correlation of the post‐rift stage to the seafloor spreading anomalies M10n to M4n that are associated with oceanic crustal domains can accommodate plate motions from 135–133 Ma to 128 Ma. The uncertainties associated with the earliest magmas of HALIP overlap with the uncertainties on the timing of the latest seafloor spreading. The first main pulse of HALIP in the Aptian at 124–120 Ma post‐dates seafloor spreading and so HALIP was emplaced in a tectonic setting that closely resembles the present state of the south and eastern Amerasia Basin. At the paleogeographic center of the HALIP, the Alpha Ridge complex is consistent with the magmatic character and history of similar Cretaceous oceanic plateau in terms of volume and duration. Plain Language Summary Prior to recently reported geochronological data from the High Arctic Large Igneous Province (HALIP), the temporal relations were highly uncertain between the tectonic stages of the onshore rift basin (Sverdrup Basin), the HALIP magmatism, and the elusive spreading history of the oceanic portion of the Amerasia Basin (Canada Basin). In the past decade, each of these components has been illuminated by new data to an extent that they can now be correlated. In the summary presented here: (a) it is proposed that the rift climax and the hyper‐extension in the continent‐ocean‐transition zone were coeval and linked processes; (b) that the breakup unconformity identified from the onshore rift basins is consistent with the earliest generation of oceanic crust; and (c) after rifting and seafloor spreading, magmatism of HALIP was a result of a mantle plume that rose to shallow levels below the thin lithosphere of the northern Amerasia Basin. Key Points Correlation of the geochronology of the High Arctic Large Igneous Province (HALIP) to rift basin tectonostratigraphy indicates that it was emplaced well after the start of the post‐rift stage Non‐correlation of the geochronology of the HALIP to oceanic magnetic anomalies in the Canada Basin indicates it post‐dates seafloor spreading These correlations support the oceanic plateau model for the HALIP, centered above the thin lithosphere of the northern Amerasia Basin

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 melting A case study for the Turkana Rift shows a correlation between lake level drops and enhanced volcanism over the last 4 Myr Sensitivity of mantle melting to lake loading is controlled by extension rate, mantle potential temperature, and lithosphere thickness

The Bengal Basin evolved as a rift-controlled extensional basin along the NNE–SSW trending Basin Margin Fault coevally with the 85° East Ridge in the Bay of Bengal during the short-lived hotspot activity south of Bhubaneswar. The basin opening post-dated the Kereguelen Plume magmatism (at ∼116 Ma), but predated the phase of continental collision that triggered the rise of the Himalaya in the north. Supply of sediments in the initial stages of basin opening was from the west, mainly through the denudation and erosion of the uplifted Precambrian Shield. Following virtually similar tectonic and depositional pattern in the entire basin, an abrupt change in depositional pattern was recorded during the Oligocene with the emergence of easterly source of sediments derived from the uplifting of Indo-Myanmarese Ranges. Between the Oligocene and Late Pleistocene different parts of the Sylhet Trough (the best-studied region in the deeper part of the Bengal Basin) received huge volumes of sediments, which resulted in deposition measuring between 10 km and over 17 km in thickness. This was followed by an equally sudden drop in the sediment supply from the east due to the basin inversion concurrently with the westward advance of the Indo-Burmese mountain front during early and midPleistocene. Followed by a short hiatus, the depositional scenario changed completely with the arrival of thick volumes of sediment during the late Pleistocene–Holocene, which covered the entire Bengal basin with the sediments brought by the Ganga and Brahmaputra from the Himalayan sources.

This study presents an integrated multi-scale characterization of pre-rift reservoirs in the October Field, Gulf of Suez, to resolve critical uncertainties in compartmentalization and resource potential. By synergizing 2D seismic, well logs, and core data, we delineate a structural framework dominated by NW-SE and NE-SW fault systems that compartmentalize the reservoirs. Our analysis establishes the superior reservoir potential of the Nubia Formation compared to the Matulla Formation. A key novelty of this work is the definition of five distinct Hydraulic Flow Units (HFUs) through the integration of Flow Zone Indicator (FZI) and Stratigraphic Modified Lorenz (SML) methods. This provides a robust, core-calibrated quantitative framework for predicting permeability in uncored intervals, significantly reducing prediction uncertainty. The workflow successfully identifies high-flow-efficiency units and optimal exploration targets, demonstrating a transferable approach for re-evaluating mature rift basins.

A magnetic anomaly combines the response of various rocks with magnetic susceptibility that eventually gives fundamental information regarding the structure and dimensions of the geological features hidden underneath. Over the years, edge detection filters have successfully separated geological structures based on the sharp discontinuity in the rock's susceptibility. Most of the filters have limitations related to (1) being unable to detect the edges of the sources simultaneously at shallow and deeper depths, (2) the response from weak and intense data being unbalanced and (3) failing to detect anomaly sources at greater depths. The present study introduces a new edge enhancement filter called the Improvised Tilt Angle of Horizontal Gradient, abbreviated as “ImpTAHG”, that uses the hyperbolic tangent function involving the derivatives of the tilt angle of the horizontal gradient. Synthetic data is used to demonstrate the filter's efficacy by comparing the response with various conventional filters. The filter avoids spurious edges and provides sharper and accurate edges from shallow, deeper, thinner and thicker sources. If the data is noisy and dominated by non-vertical magnetization, the interpreter may have to opt for upward continuation and reduction to magnetic pole transformation, respectively. The filter is applied on the aeromagnetic data over the Cambay rift basin, India, and successfully mapped the unidentified structural features and major tectonic blocks buried under sediment cover. The ImpTAHG filter proves to give a better prospect in the interpretation of magnetic data.

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.

The Red Sea basin is considered one of the world-class examples of continental rifting, breakup and seafloor spreading. This study focuses on the structural framework of the northwestern part of the Egyptian Red Sea margin and the identification of the different rift domains using surface and subsurface data. Subsurface mapping using 2D seismic and borehole data indicates that the northern part of this area represents the continuation of the structural style of the southern Gulf of Suez rift as the mapped structures are mainly down to the northeast main faults with southwest dipping strata. In addition, two negative flower structures have been observed and represent the southern continuation of the Gulf of Aqaba -Dead Sea left-lateral transform fault system. The NE dip of the main rift-parallel faults that characterizes most of the study area flips in the southern part of the area (south of the Duwi accommodation zone) where the fault blocks dip northeastward and the main faults dip SW. Based on the integration of the structural style, continental crust stretching factor ( β ) and the crustal thickness, the northwestern margin of the Red Sea can be divided into proximal domain, necking domain and potential hyper-extended domain that seems to extend southeast of the area of study and may represent the future locus for oceanic crust development in the northern Red Sea. Each domain is characterized by a distinct structural style and subsidence profiles, and variable preservation and distribution of the pre-rift and syn-rift stratigraphic units.

The Middle Triassic volcano-sedimentary successions deposited on the passive continental margin during a period of intense extensional tectonics related to the opening of the Neotethys Ocean were investigated in NW Croatia. A new palaeogeographic term, the Northwestern Croatian Triassic Rift Basin (NCTRB), is introduced for these successions. Pelagic sediments were deposited on top of older shallow-marine carbonates from the early Illyrian to possibly late Ladinian. Pelagic limestones containing Illyrian ammonites and redeposited benthic foraminifers of the same age indicate the existence of a contemporaneous shallow-marine carbonate environment that supplied material to the deeper parts of the basin. Stratigraphically stacked volcanic and volcanogenic rocks are intercalated with pelagic sedimentary rocks. Submarine basaltic rocks, geochemically characterized as trachy-basalts, are related to deep-rooted faults. Trachy-basaltic hyaloclastites, found intercalated within pelagic limestones, were formed by the quenching of magma that came into contact with cold sea water and subsequent resedimentation of the newly formed basaltic fragments. The majority of volcanogenic deposits belong to the Pietra Verde deposits found higher in the sections. The material for these deposits was produced by explosive volcanic eruptions and deposited by gravitational mechanisms, including pyroclastic density currents. Radiolarians from intercalated radiolarian cherts indicate late Illyrian to early Fassanian age for volcanic activity, as well as episodic eruptions and deposition of pyroclastic material. The uppermost part of the NTCRB successions is characterized by secondary volcaniclastic deposits generated by the rapid reworking of unconsolidated pyroclastic detritus and is deposited as medium- to fine-grained turbidites, marking the gradual filling of the basin. Based on regional correlations, late Ladinian is the most likely age for these deposits, indicating a significant stratigraphic gap in the NTCRB successions.

Comparative analyses of petroleum generation potential, reservoir volume, frackability, and oil mobility were conducted on 102 shale cores from the Dongpu Depression. Results show the shale has high organic matter contents composed of oil-prone type I and type II kerogens within the oil window. Various types of pores and fractures exist in the shale, with a porosity of up to 14.9%. The shale has high brittle mineral contents, extensive fractures, and high potential for oil mobility due to high seepage capacity and overpressure. Although the petroleum generation potential of the shale at Well PS18-8 is relatively greater than that at Well PS18-1, oil content of the latter is greater due to the greater TOC . The porosity and fracture density observed in Well PS18-1 are greater and more conducive to shale oil enrichment. Although the shales in Wells PS18-1 and PS18-8 have similar brittle mineral contents, the former is more favorable for anthropogenic fracturing due to a higher preexisting fracture density. Besides, the shale at Well PS18-1 has a higher seepage capacity and overpressure and therefore a higher oil mobility. The fracture density and overpressure play key roles in shale oil enrichment.

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.