Basin Research - Volume 33, Issue 4, 2021

West off Martinique (Lesser Antilles), the Grenada Basin submarine sediments were affected by the emplacement of Debris Avalanche Deposits (DAD). Montagne Pelée Volcano has experienced three major flank collapses during the last ca. 127 kyrs, resulting in a cumulated volume of up to 300 km³ offshore. Using a combination of geophysical and geotechnical data, we investigate the effect of these debris avalanches emplacements on the basin hydrogeology and their relationship with the observed sediment deformation in the seismic and coring data. The geotechnical test carried on IODP‐340 cores samples reveal four sediment types within the basin with distinctive mechanical and hydraulic properties: proximal volcanoclastics, distal volcanoclastics, hemipelagic and ash‐rich sediments. These results, together with margin stratigraphic models obtained from seismic reflection data, were used as inputs for the numerical finite‐element model. This model shows that the coupling of the sediment properties with the mid‐ to low‐sedimentation rates results in the development of low overpressures prior to the first flank collapse at 127 ka. However, the emplacement of the first two DADs, between 127 and 36 ka, developed high overpressures ratios (λ^* > 0.9) in the easternmost part of the Grenada Basin. According to the model, the sudden compaction of the pre‐existing sediments due to the DADs load created fluid flow velocities up to 7 times higher than the hydraulic conductivities, which would have thus reduced the sediment bearing capacities and shear strength, favouring their mobilization and deformation. From 127 to 36 ka, the sea‐floor sediments suffered a long‐term deformation driven by the combination of the weight of the emplaced material and the persistence of high overpressure ratios through time. This deformation propagated tens of kilometres away from the DAD’s emplacement and it is possible that still continues today due to the persistence of low overpressure ratios. This long‐term and long‐distance deformation and persisted overpressures are a key factor to take into account in the framework of a geohazards evaluation in areas recurrently affected by earthquakes and volcanic flank collapses.

The Grenada Basin was affected by at least two flank collapse debris avalanches from the Montagne Pelée volcano during the last 130 ka. These mass‐transports combine with their derived overpressures built up may cause the long‐term and long‐distance deformation that can be observed nowadays.

Evaporites are typically described as impermeable seals that create some of the world's highest reservoir pressures beneath the salt seal. However, several laboratory studies demonstrate that evaporites can retain open pore spaces that hydraulically connect the sediments above and below them in sedimentary basins. During the Messinian Salinity Crisis (5.97–5.33 Ma), up to 2,400 m thickness of evaporites were rapidly deposited in the Western Mediterranean, which may have generated high pore fluid overpressure in the basin sediments. Here we use one‐dimensional numerical modelling to quantify the temporal evolution of overpressure at two distinct locations of the Western Mediterranean, the Liguro‐Provençal and Algero‐Balearic basins, from the Miocene to Present. We reconstruct the sedimentation history of the basin, considering disequilibrium compaction as an overpressure mechanism and constraining model parameters (such as permeability and porosity) using laboratory experiments and the literature. In the Liguro‐Provençal basin the highest overpressure of 11.2 MPa occurs within the halite during deposition of Pliocene to Quaternary sediment, while in the Algero‐Balearic basin at the base of the Emile Baudot Escarpment, the highest overpressure of 3.1 MPa also occurs within the halite but during stage 3 of the Messinian Salinity Crisis (5.55–5.33 Ma). In the Algero‐Balearic basin an overpressure of 3.1 MPa could have been sufficient to hydro fracture the sediments, which agrees with the development of fluid escape features observed on seismic reflection profiles. In general, our models with evaporite deposition rates above 20 m kyr⁻¹ and permeabilities below 10^–18 m², suggest that high overpressure, approaching lithostatic, can be generated in salt basins.

Evaporites are typically described as impermeable seals, however several laboratory studies including this one show that pore fluid flow can occur through them. In this study, we used numerical modelling and laboratory observations of low permeability evaporites to quantify overpressure in the Western Mediterranean from basin inception to present day and estimate overpressure magnitudes triggering fluid expulsion events during the Messinian.

Deep‐water stratigraphic successions from syn‐ to post‐rift stages are an archive of evolving physiographic configurations, and can record axial and transverse sedimentary sources. The healing of topography decreases the influence of syn‐rift structures on sedimentation patterns and transport processes over time, which leads to a long‐term transition from dominantly axial to transverse dispersal patterns. The Halten and Dønna terraces, offshore mid‐Norway, comprise a series of rift‐related sub‐basins established during the Jurassic, which were infilled with sediments during the Cretaceous. The Cretaceous Lysing Formation developed as slope‐ and basin‐floor fans within a series of weakly confined post‐rift sub‐basins with some shallow marine deposits interpreted on the basin margins. A deep‐water setting is supported by seismic interpretation, and bed type and architectural element analysis in all cored and uncored wells in the area. We document that an axial submarine fan system was active throughout the post‐rift stage due to subtle inherited topography from syn‐rift structures, which interacted with locally sourced transverse sediment sources. This led to a complicated stratigraphic architecture, with lobe fringe deposits of the axial fan system juxtaposed with channel‐fills and channel‐lobe transition zone deposits of transverse systems. The refined palaeogeographic reconstruction of the Lysing Formation illustrates how subtle topography can impact sediment routing patterns many millions of years after the end of rifting and can be used for palaeoenvironmental interpretations in other post‐rift settings.

Palaeogeographic reconstruction of the Cretaceous Lysing Formation, offshore Norway, showing the interaction of axial and transverse deep‐water systems in a post‐rift setting.

Map of the Paraná catchment to Pelotas basin routing system. The Pelotas basin is highlighted with the Plio‐Quaternary isopach map.

In this paper, we propose a high‐resolution (HR) sedimentary budget quantification at basin‐scale for the Cenozoic deposits of the Pelotas Basin (South Atlantic). A new workflow is implemented including five main steps: (1) basin‐scale analysis and characterization, (2) quality control and selection of reference 2D dip‐sections, (3) HR seismic stratigraphy analysis, (4) sediment supply estimation taking into account lithology and porosity corrections and then (5) the estimation of the sedimentary budget curve including 41 time‐intervals for the last 65 Myr. Variance ranges were determined considering the parameters of the method on the case study. The main uncertainties are related to the seismic velocities for the time‐to‐depth conversion (5%–22%), the method for lithological parameters quantification and associated porosity correction (4.4%–14.3%), the absolute ages of stratigraphic markers (1%–25%), and the proportion of in‐situ sediment production (0.3%–0.5%). For the very first time, this method allows the identification of several cycles from an entire sedimentary basin fill characterized by pulses of sediment supply (Qs) whose growth phase lasts less than 1 Myr, followed by a constant phase lasting 1–2 Myr, and finally an exponentially decreasing phase lasting 2–5 Myr. These pulses alternate with phases where the sediment supply was very low for intervals of ca. 1–5 Myr. Ten major pulses were recognized during the Cenozoic. We propose that the sediment supply dynamic in the Pelotas basin records the orogenic phases of the Andes located more than 2,000 km upstream. The recorded Qs pulses in the basin are out of phase with respect to the active tectonic phases of the Central Andes. Finally, by comparing the volume of preserved sediment and the production capacity of the catchment, we suggest that a source of sediment in addition to the Brazilian craton and the Andes should be envisaged, potentially associated with deep‐water oceanic circulation.

Sea level is thought to be the primary driver of alternating deposition of carbonate and siliciclastic sediment in shelf settings, with carbonates dominating during transgressive/highstands and siliciclastics during lowstands. Although sediment supply is critically important for shelf‐margin growth in siliciclastic systems, few studies demonstrate its impact on mixed carbonate‐siliciclastic systems. The Permian Basin in Texas, United States, provides an opportunity to investigate the basin evolution regarding the source, sediment routing and particularly shelf/slope growth from syn‐ to postorogenic phases during alternating carbonate and siliciclastic sedimentation. Published detrital zircon data show that the proportion of orogen‐related sources decreased significantly from an earliest Permian synorogenic phase (ca. 298 Ma) to a Leonardian (ca. 280–271 Ma) postorogenic phase, in concert with a grain‐size change from fine‐ to medium‐grained sand to silt. Although along‐strike lateral variabilities exist on the shelf margin, the shelf‐margin evolution characteristics show a significant difference among the Northern Shelf, Eastern Shelf and Central Basin Platform. The synorogenic Eastern Shelf exhibits a significant higher progradation rate than does the postorogenic Northern Shelf. The progradation and aggradation ratio of siliciclastic‐rich intervals in the Eastern Shelf is significantly higher than those of carbonate‐rich intervals in the Eastern Shelf and carbonate‐ or siliciclastic‐rich intervals in the Northern Shelf. In contrast, the Central Basin Platform, with no siliciclastic sediment supply, records almost no progradation regardless of orogenic phases. There is an increase in slope gradient with decreasing sediment supply during this second‐order sequence from the Permian Cisuralian Series to the end of the Guadalupian Series. This study demonstrates that tectonically driven siliciclastic sediment supply was the main mechanism controlling the shelf and slope evolution in alternating siliciclastic and carbonate deposition.

Late Palaeozoic continental‐continental collision and related sediment routing changes and evolution of sedimentary basins in southwestern Laurentia.

The configuration and kinematics of fold‐thrust belts are essential for clarifying the plate boundary conditions through which ancient orogenic belts evolved. Temporal and spatial variations in extension versus contraction within convergent plate margins are related to changes in plate kinematics and subduction geometry. The Yanshan Mountains, located along the northeastern margin of the North China Craton and bounded by the Central Asian Orogenic Belt to the north and the Pacific subduction zone to the east, underwent multiple phases of intra‐continental deformation during the Mesozoic. The issue of whether early Mesozoic deformation was extensional or contractional has remained controversial. New regional structural mapping and detailed sedimentological investigations, coupled with age constraints provided by zircon U‐Pb geochronology, provide sufficient temporal and spatial resolution to show that shortening and thrust‐top basin systems dominated during the early Mesozoic. Our results show that the Dengzhangzi Basin within the Lingyuan fold‐thrust belt developed during the construction of a major Late Triassic Chapeng antiformal‐stack duplex system, with episodic, east‐vergent forward‐breaking thrusts and subsequent ‘beheading’ by out‐of‐sequence, top‐to‐east thrusting in the latest Triassic or earliest Jurassic. The neighbouring Guojiadian Basin in the east was generated during top‐to‐SSE sinistral transpression along the Niuyingzi thrust system in the Middle to earliest Late Jurassic. These results support a new model of early craton decratonization involving (a) thrusting along the northern margin of the North China Craton and (b) transpressional deformation in the east driven by the Central Asian Ocean collision and flat‐slab subduction of the Palaeo‐Pacific Plate beneath the East Asian continental margin. Our findings suggest that large‐scale shortening and crustal/lithospheric thickening, triggered by flat‐slab subduction in the North China Craton, were fundamental components of craton decratonization. Subsequent slab roll‐back during the Cretaceous led to lithospheric thinning and crustal extension in the North China Craton.

The Late Triassic Chapeng thrust and the Dengzhangzi Basin system in the Yanshan Mountains of the North China Craton were an antiformal stack duplex with a frontal depression.

The Upper Ediacaran to Lower Cambrian of the Sichuan Basin in South China has long been considered to be dominated by shallow‐water deposition. Hydrocarbon exploration, however, has revealed that a NW‐SE trending intraplatform trough formed in the basin during the same period. Although different models have been proposed, the formation and evolution of the trough are still not fully understood. In this study, we investigate both the origin of the intraplatform trough and the formation of the Sichuan Basin by integrating seismic interpretation, well correlation and tectonic subsidence analysis. The seismic and well data clearly show three stages of development of the trough. The first stage, in the early Late Ediacaran, is characterized by considerable thinning of the lower two members of the Upper Ediacaran from the platform margins to the trough. In the second stage, in the late Late Ediacaran, the platform margins backstepped and the extent of the trough expanded significantly to a width of ca. ~400 km. The third stage, in the early Early Cambrian, was dominated by gradual filling of the trough and onlapping of the platform margins. Backstripped tectonic subsidence curves show one, or two closely spaced episodes of linear subsidence starting at ~550 Ma and then decreasing exponentially until ~450 Ma. The shape of the subsidence curves is consistent with formation of the Sichuan Basin by low, and slow amounts of lithospheric stretching of thickened cratonic lithosphere. The tectonic subsidence increases from the centre to the NW of the basin. Interestingly the margins of the trough do not correlate with contoured values of increased tectonic subsidence and we infer that the trough was a palaeogeographic embayment in a large carbonate platform that developed in a broad, ramp‐like area of slow and low subsidence tilting down to the proto‐Tethyan ocean located to the NW of the basin.

An intraplatform trough and associated platform margins formed in the Sichuan Basin, South China, during the Late Ediacaran to Early Cambrian. Seismic data show three stages of development of the trough. The first stage is characterized by considerable thinning of the lower two members of the Upper Ediacaran from the platform margins to the trough. In the second stage, in the late Late Ediacaran, the platform margins backstepped and the extent of the trough expanded significantly. The third stage, in the early Early Cambrian, was dominated by gradual filling of the trough and onlapping of the platform margins. Integrating with tectonic subsidence analysis, we infer that the trough was a palaeogeographic embayment in a large carbonate platform.

Panel a: Conceptual classification of mass movements into free‐flow and no‐slip flow (redrawn after Sobiesiak et al., 2018). Panel b: Kinematic indicators observed in the study area include variably oriented convolute fabrics, basal shear zone fractures (cut‐offs or cracks), striations, grooves and monkey fingers (responsible for peeling back of the BSZs). Panel c‐ Classification of the five interpreted mass transport deposits into those with free flow and no‐slip flow. The BSZ for MTD 1, 3, 4 and 5 is marked using blue, green, pink and orange lines.

This work examines the mode of basal to substrate interaction, and flow dynamics of recurrent mass wasting events from a high‐quality 3D seismic reflection data. The Taranaki Basin, offshore New Zealand offers a unique environment to understand these processes, as the Neogene succession of the area preserves vertical stacks of mass transport deposits (MTDs) from the Miocene to Pliocene. The approach used here combines seismic interpretation of the basal shear zones (BSZs) of the MTD, seismic attribute analyses and colour rendering of both RMS amplitude and energy gradient maps. The five mass transport deposits are characterized into blocky‐MTDs consisting of moderate to high amplitude and variably deformed rafted blocks, and chaotic masses composed of slides and debris flow deposits. Classic examples of kinematic indicators at the BSZ of the MTDs akin to free‐slip flow processes such as liquefaction, hydroplaning and shear wetting are convolute flow fabrics and basal shear zone cut‐offs (fractures). Striations, grooves, mega scours, U‐ and V‐shaped scours, substrate erosion, monkey fingers (peel backs), substrate deformation and shearing are associated with no‐slip flows, suggesting that the mass movements efficiently interacted with the underlying substrate. Importantly, the intersection of different kinematic indicators along the BSZs of all the MTDs suggests an overlap of flow regimes, flow overprinting and transformation during mass movement. Although basal tooling by rafted blocks seems dominant during remobilization of the blocky MTDs, the presence of other kinematic indicators signifies combined mechanisms involving both free‐flow and no‐slip processes during their translation. The classification scheme evaluated here innovatively shows mass movements habitually occur through a combination of flow mechanisms rather than an independent flow regime.

Records of sedimentation and deformation in trench‐slope basins contain valuable tectonic information about the associated oceanic subduction zone. Here, we present a multidisciplinary study on newly discovered late Permian–Triassic sedimentary successions in the >500‐km‐long Central Qiangtang metamorphic belt (CQMB) to better understand the type of basin and the concomitant tectonism. The Mayer Kangri succession contains lithofacies associations of submarine fan siliciclastic rocks, slope‐environment limestone, deep marine chert and minor olistostromes from the forearc basin. The conodont assemblages and sandstone and andesite interlayers yield continuous stratigraphic ages from the Lopingian to middle Norian. The clastic sediments had two provenances, including the epicontinental arc in the North Qiangtang block (NQB) and synchronous volcanism in the accretionary wedge. Moreover, a large suite of the Anisian–early Carnian radiolarian cherts (>30 m thick) was discovered in the Lanling area. Regionally, the CQMB shows evident spatiotemporal variations in late Permian–Triassic sedimentation, with a general depositional trend of southward deepening and getting younger. The three identified subzones include a bathyal setting, a carbonate platform setting and a deep marine setting from north to south. These observations indicate that the late Permian–Triassic sedimentary successions in the CQMB were deposited in a trench‐slope basin environment during the northward subduction of the Longmu Co–Shuanghu Tethys Ocean beneath the NQB. Generally, the CQMB and the concomitant trench‐slope basin is among the well‐preserved ancient analogs characterized by extensional tectonism. The syndepositional horst‐graben‐like structure, forearc basin‐derived olistostromes, abyssal radiolarian cherts and synchronous volcanism provide new implications for the geological evolution of the trench‐slope basin.

The late Permian–Triassic trench‐slope basin in the CQMB showing the correlation between spatiotemporal variations in basin sedimentation and the extensional tectonism of the accretionary wedge.

Ordovician carbonate rocks on the northern slope of the Tazhong Uplift in the Tarim Basin are modified to varying degrees by hydrothermal fluids related to multiple tectonic‐thermal events, but the nature, origin and circulation mechanisms of such hydrothermal fluids remain debated. In this article, in situ rare‐earth elements and yttrium (REE + Y) concentrations, previously published geochemical datasets and petrographic investigations are integrated to develop a thermo‐tectonic evolution model to improve understanding of silicification and dolomitisation occurring in the interior of the craton basin. δ³⁰Si values, REE + Y ratios and fluid mixing models using modern black smoker fluid and seawater indicate that magma‐sourced hydrothermal fluids, rather than basinal brine heated by magmatism, are responsible for the precipitation of cherts. Petrological and geochemical evidence suggests that deep‐seated, ultramafic‐derived hydrothermal fluids and/or magmatic fluids associated with Permian volcanism may have been involved in the formation of hydrothermal dolomites in the study area. Accompanying formation and reactivation of the strike‐slip faults on the northern slope of the Tazhong Uplift, small volumes of hydrothermal fluids might have been triggered by seismic pumping. The early formed strike‐slip fault systems may also have served as conduits for the subsequent large‐scale transport of deep‐seated, ultramafic‐derived thermal fluids and/or Permian magmatic fluids, along which fluids were transported upwards at high flow rates. Carbonation of ultramafic rocks through interaction with deep‐seated hydrothermal fluids rich in CO2 may have served as a magnesium and silica source for dolomitisation and silicification. Trans‐tensional troughs on NNE‐trending strike‐slip faults with positive flower structure are favourable locations for dolomitisation and silicification.

Ultramafic‐derived or magmatic‐sourced fluids transported upward along strike‐slip faults, and contributed to the local precipitation of hydrothermal dolomites and cherts.

Constraining the timing and volume of sediment dispersal in an ancient sedimentary system is vital to understand a basin's infill history. One preferred method for a first‐order approximation of ancient sediment load estimates, the BQART model, is based on empirical observations of modern river systems relating basin morphology, topography, climate, run‐off and bedrock characteristics. Despite the popularity of such methods, a comprehensive assessment on the validity of using modern river observations to measure sediment load on geological timescales is lacking. Here, we investigate the uncertainties, sensitivities and practicalities surrounding the use of modern empirical observations in general and the BQART model in particular, to evaluate ancient sediment river loads. Although catchment area and relief are the least constrained parameters in an ancient sedimentary system, the temperature parameter may have an even more significant impact in the range of predicted sediment load estimates using a BQART approach. The applicability of BQART is most suitable for regional to continental scale source‐to‐sink systems that are based on robust paleogeographic and paleoclimatic models of cold (<2°C) or warm temperate (>8°C) climates. One further needs to consider the high amplitude discharge events that can dominate the stratigraphic record which are not captured by historical observations of sediment load over a 30‐year period. In addition, our limited understanding of bedload material transport and an unknown pristine environment in the Anthropocene reduce the reliability of modern sediment load estimates for the ancient. Mass budget estimates in deep time based on empirical relationships of modern river systems can thus provide first‐order estimates within an order of magnitude but need to consider the limitations imposed by extrapolating the modern to the ancient. Here, we present a framework to consider the suitability of the BQART method for ancient source‐to‐sink mass budget analyses.

The BQART formulais an empirical relationship between observed total suspend sediment load (Tss) and catchment area (A), relief (R), temperature (T), water discharge (Q) and erodibility (B) in modern river systems. Application of the method for anancient S2S mass budget study requires: (1) an assessment of the methods suitability, (2) a paleogeographicreconstruction, (3) a paleoclimate reconstruction and (4) Monte Carlo simulations.

Recumbent folds in the Messinian Evaporites of the Eastern Mediterranean, formed by simple shear deformation of upright folds during multiphase salt tectonics.

Several salt basins globally have been subject to multiphase deformation. The geometry of structures formed within a salt sheet during an early phase of deformation can be concealed by overprinting during later deformation phases, impeding an informed investigation into the early drivers for salt flow. The layered Messinian Evaporites in the deep basins of the Eastern Mediterranean have undergone a Late Messinian phase of deformation, punctuated by truncation of the top of the deformation structures, followed by a Late Pliocene‐Recent phase of deformation. Seismic reflection data show that the Messinian Evaporites are internally dominated by contraction structures that verge basinward in the Late Pliocene‐Recent flow direction, with several apparent detachments. Planform linear trails of fluid escape pipes, documented in the North Levant Basin, that cross‐cut the Messinian Evaporites present natural passive markers for the internal flow kinematics of the salt sheet throughout the Late Pliocene‐Recent phase of deformation. Using the Couette (simple shear) strain profile implied by the fluid escape pipes, we remove the effects of the Late Pliocene‐Recent deformation through cross section and map restorations. The subsequent geometries are far simpler, with upright folds that are now vertically aligned. Once apparently detached structures are demonstrably connected through the Messinian Evaporites. The vergence of the present day intrasalt folds can be taken as an indicator for the Late Pliocene‐Recent flow direction and distinct deformation geometries that connect at various levels through the salt sequence once retro‐deformed can assist when interpreting the salt flow profile. The retro‐deformation is essential for how intra‐Messinian deformation and its drivers are interpreted going forward. Furthermore, simple shear deformation results in erroneous apparent percentage shortening calculations as line length is not conserved, obscuring the strain from the pre‐Pliocene deformational phase. The methodology employed here has important implications for all salt basins that have undergone multiphase deformation.

Potential field data, reprocessed regional 2D seismic reflection profiles and 3D seismic tied to wells were used to study the late Devonian‐Permian development of the Nordkapp Basin in Barents Sea. The composite basin can be subdivided into the northeastern, central and southwestern segments that developed above a basement that contains elements of the Timanian and Caledonian regimes. The transition between the Timanian and Caledonian structures is positioned below the central basin segment. The rheological properties, locations, orientations and interaction of inherited structures together with two subsequent extensional phases, defined the presalt rift architecture and gave rise to seven subbasins within Nordkapp Basin. During the late Devonian‐early Carboniferous NE‐SW oriented extension, the basin consisted of two regional half‐grabens (northern and southern) separated by an interbasin ridge. During the late Carboniferous, the shift of extension direction to NW‐SE orientation reshaped the two regional half‐grabens. In particular, an interbasin transfer zone divided the northern regional half‐graben by separating its hinged‐margin portion (incipient northeastern segment) from the deeper part (incipient central segment). At the same time, the elevated interbasin ridge separated the incipient central and southwestern segments. Internally within the seven subbasins, the evolving structural elements including cross‐cutting master faults and structural highs have influenced the deposition and character of the Pennsylvanian‐lower Permian layered evaporite sequence and the distribution of subsequent salt structures. We suggest that the synrift to early postrift processes, relative depth of each subbasin, arrangement of the structural highs and depositional palaeo‐environment all controlled the thickness and facies of the layered evaporite sequence. The latter in combination with the presalt architecture comprised a laterally varying in thickness and character substratum that during the earliest Triassic influenced the sediment routings and deposition of the progradational system arriving in Nordkapp Basin. The study outcomes are pertinent and applicable to other salt‐influenced rift basins worldwide.

The rheological properties, locations, orientations and interaction of the Timanian and Caledonian structures together with two subsequent extensional phases strongly influenced the presalt rift architecture and gave rise to seven subbasins in the Nordkapp Basin. The relative depth of each subbasin in contrast to the margin, cross‐cutting master faults, structural highs arrangement and depositional paleo‐environment controlled the thickness and facies of the synrift to early postrift layered evaporite sequence.

Recent studies on the genesis of sedimentary native sulfur deposits indicate diagenetic mid‐low temperature Bacterial Sulfate Reduction (BSR) as the main process, involving organic compounds (kerogen/hydrocarbons), bacterial colonies and gypsiferous rocks. In the peri‐Mediterranean area (Southern Spain, Sicily, Northern Apennines, Israel), the main sulfur accumulations are always associated with late Miocene sulfates and organic‐rich successions encompassing the Messinian salinity crisis (MSC). In particular, the Messinian successions of the Apennine‐Adriatic foreland basin system, due to a large amount of high‐resolution stratigraphic data, represent a perfect case study for understanding the diagenetic conditions controlling the development of the BSR process during sedimentary basin evolution. In this work, thermal models performed in three sub‐basins in a sector of the Northern Apennines comprised of the Sillaro and Marecchia rivers (Italy), calibrated by means of organic and inorganic geothermometers, indicate a general thermal immaturity of the studied successions attained as a result of a constant heat flow similar to the present day one (ca. 40 mW/m²) since Late Tortonian and lithostatic loads between 615 and 1,710 m depending on different sub‐basins. These results suggest that the MSC deposits experienced maximum temperatures between about 39°C and 65°C. Temperatures derived from thermal models have been used to constraint occurrence of the diagenetic BSR associated with evaporitic deposits providing thermal constraints in sulfur genesis as well as new useful thermal‐constraints for basin analysis studies.

The manuscript presents the first attempt to define the diagenetic conditions (burial and related paleo‐temperatures) for sulfur formation in relationship with the deposits generated by the Messinian salinit crisis.

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The division and correlation of sequence stratigraphy are one of the essential steps in petroleum exploration. To comprehensively utilize the sequence stratigraphic information implied in multiple wireline well logs and improve the accuracy and reliability of sequence stratigraphic division, based on the edge detection, optimal partition, and natural evolution theories, and realizes the information fusion (formed one ‘chromosome’) of multiple wireline well logs (named as ‘genes’) which can reflect the feature information of sequence stratigraphy by using multipopulation genetic algorithm (MPGA) based on Fisher algorithm, in this study, geophysical data (wireline well logs and 3D seismic data) were used for spectral trend attribute analyses (wavelet transform, maximum entropy spectrum, time‐frequency analyses, and integrated prediction error filter). Since the seismic reflection characteristics of K1q were difficult to identify and considering subjective factors in conventional methods, a MPGA was also used to intelligently identify the sequence stratigraphy framework of the Lower Cretaceous Qingshuihe (K1q) Formation. Since the MPGA is an optimization algorithm, the code was run 10 times for accuracy with changes in the dividing layers. The optimal parameters in the process of data fusion (gene combination process) are selected. The sequence boundaries (SBs) searched by the MPGA matched those of the spectral trend attribute analyses, confirming that the MPGA was an effective, fast, and user‐friendly tool for defining the main SBs. MPGA can provide an optimal layering scheme (‘elite population’) through simultaneous searching at multiple depth ranges (‘multipopulation’), recording the optimal SBs (‘elite individuals’) of each population and making the results more convinced. Although simulation solutions may not be unique, the MPGA still provides us a chance to gain some insights into the details of the stratigraphy. Based on this intelligent identification, the maximum flooding surface, two first flooding surfaces (FFS), and three SBs were defined in K1q. The cyclic patterns (prograding, aggrading, and retrograding) were identified. They showed the relationship between accommodation space (related to tectonic subsidence of the Chemo paleo‐uplift) and sediment supply. In addition, dynamic time warping (DWT) technique was used for sequence discrimination and correlation on the integrated prediction error filter analyses curve. A massive pebbly sandstone set, named ‘bottom sandstone,’ was identified in the lowstand system tract of SQ1 (K1q¹), constrained by SB1 and FFS1, which was a favourable hydrocarbon exploration target.

The applications of MPGA‐DTW utilized for division and correlation of stratigraphic sequence in this study is based on multiple wireline logs. The integrated results of the sequence boundaries searched by the MPGA were consistent with the sequence boundaries revealed by commonly used approaches based on geophysical data and spectral trend attribute analyses (wavelet transform, maximum entropy spectrum, time‐frequency analyses, and integrated prediction error filter). This study reveal that the combination of MPGA‐DTW may be a powerful tool for intelligent sequence stratigraphy division and correlation.