Basin Research最新文献

Exhumation affects sedimentary basin evolution by influencing structural, pressure and temperature dynamics, thereby impacting energy resource formation. Compaction-based methods are widely used to quantify exhumation, utilising sonic and porosity data to track sediment uplift from its maximum burial depths. However, uncertainties arise from applying empirical compaction models developed for specific geological regions, highlighting the need for region-specific models. Even such region-specific models contain uncertainties, which can compromise exhumation estimates. We, therefore, develop a probabilistic compaction model for the Northwest Shelf Basins using sonic data from normally compacted and unexhumed shales from the Northern Carnarvon Basin (NCB). The model's robustness is estimated using MCMC, and uncertainty propagation analysis is employed to assess the impact of model uncertainty on the model's predictive applications. The model shows exponential porosity reduction with depth, demonstrating rapid compaction from the surface to ca. 2 km and slower compaction thereafter. The model is then applied to interpret new datasets from the Canning, Gippsland and NCB regions. The results reveal that while some parts of the NCB exhibit normal compaction without exhumation, others were significantly exhumed. Conversely, Canning and Gippsland Basin data indicate signs of significant exhumation, as suggested by previous studies, thereby confirming the model's effectiveness outside the Northwest Shelf. Since the model could not explain data from exhumed regions, we inferred new models incorporating “exhumation” parameters to interpret the complex compaction histories of these areas, and the best-fitting models were selected using the Bayes Factor method. Uncertainty analysis revealed that the impacts of model uncertainty on exhumation estimates are consistent across wide depth ranges. Our findings highlight the need to refine compaction models for better predictive reliability and informed resource exploration in sedimentary basins.

Detachment fault system associated with a mature metamorphic core complex (MCC) is still not well understood. Using high-resolution 3D seismic data, we analyse the geometries and kinematic development of detachment fault system associated with a mature and exhumated MCC in the northern South China Sea rifted margin, with an emphasis on the MCC-associated faults within the supra-detachment basin. Faults within the supra-detachment basin can be classified into three stages, the pre-MCC, syn-MCC and post-MCC faults, based on their formation time relative to the MCC. The NE to NEE-striking pre-MCC faults developed in the early syn-rift 1 stage, and the NW to WNW-striking post-MCC faults were both dominated by the regional tectonics and are perpendicular to the extension directions. While the syn-MCC faults, synchronous with the MCC development in the late syn-rift 1 stage, show overall EW-striking, consistent with the long axis of the KP MCC. These syn-MCC faults were well developed and are significant in shaping the basin architecture. Besides, the syn-MCC faults are regularly distributed in the four zones overlying the convex-upward master detachment fault surface, and are defined in this study as a synthetic fault zone, an upper collapse synformal-graben fault zone, a lower collapse antiformal-graben fault zone and an antithetic fault zone respectively. These four fault zones show distinct features and evolutionary patterns, and have a closed relationship with the rolling-hinge process of the KP MCC. An evolutionary model is established for the development of MCC-associated detachment fault system which should have global implications.

The Cenozoic topographic growth of the Tibetan Plateau is a pulsed, polyphase process that still requires more constraints. The Cenozoic sedimentary record of the Ningnan Basin, a continental basin located adjacent to the northeastern margin of the Tibetan Plateau, is a key archive for recording the surface evolution of the Tibetan Plateau. This work reports new provenance data (apatite fission-track, apatite U–Pb dating, and trace element analysis on the same individual grains) from the Oligocene–Pliocene sedimentary sequence that filled the Ningnan Basin. The data set shows variations in provenance patterns through the Miocene which are related to the tectonic evolution of the northeastern margin of the Tibetan Plateau. In contrast to a primary provenance from the Western Ordos Block (WOB) during the Oligocene, the Miocene sediments were mostly derived from the recycling of Mesozoic successions that occur along the northwestern Haiyuan Fault, documenting it was active in the last ca. 15 Myr. These sediments, in turn, were derived from different orogenic blocks but mainly from different segments of the Qilian Mountains. We show that the Late Miocene–Pliocene sediments were primarily derived from transpressional uplift along the Haiyuan Fault, which affected regions such as the Liupan Mountains. Progressive northeastward migration of tectonic stress since the Middle Miocene has induced extensive regional deformation in the northeastern Tibetan Plateau, particularly along the Haiyuan Fault. The provenance record of the neighbouring Cenozoic basins is a key archive for deciphering this tectonic evolution.

Focusing on the late Miocene succession stratigraphic successions including the evaporite deposits from the Messinian salinity crisis (MSC) of the Adriatic foreland basin, a revision of available boreholes and seismic data allowed us to recognize the presence of reservoirs and seals systems that can be considered of potential interest for the storage of natural and synthetic gas. Potentially good reservoir sites can be found where porous rocks referable to siliciclastic turbiditites (Marnoso-arenacea and Laga Fms) or shallow-water carbonates (Bolognano Fm) preferentially involved in anticlinal structures and covered by thick MSC evaporites, which may represent effective reservoir seals. The integrated reconstruction of porous rocks distribution and facies, thickness, and lateral continuity of the overlying evaporites, allows the identification and zonation of geological settings in the Adriatic foredeep, backbulge and foreland with peculiar stratigraphy and deformations, only partially considered before, that may deserve consideration in the research of potential gas storage sites.

Large clastic dykes (the Harutori-Taro and Harutori-Jiro dykes) and smaller dykes are exposed in the underground Kushiro Coal Mine (KCM), Japan. This study examines these dykes as a case study to investigate the geological conditions and fluid flow history that lead to the development of large clastic dykes in basins. The composition of the dykes indicates the Beppo and/or Harutori formations as their parent unit. Crystallite size distribution (CSD) analysis reveals Ostwald ripening of the kaolinite in the kaolinitised feldspar from the dykes, suggesting stagnant conditions in the parent unit before the dyke was formed. In contrast, smectite CSDs and the high carbonate content of the dykes suggest that large volumes of fluid flowed through the dykes along the established hydraulic gradient, which was triggered by the breaking of the upper seal. The isotopic and chemical compositions of the calcite and aragonite in the dykes, with moderate siderite and rhodochrosite content, indicate the fluid was a warm (>30°C) mixture of freshwater and saltwater, which was transferred from deeper levels of the parent unit towards the crest of an anticline. Immediately after sand injection, the semi-closed system of the parent unit near the root of the large dyke was transformed into a major flow channel for overpressurised fluids. Subsequently, a large volume of fluid flowed along the vertical conduit (or dyke) over a long period of time (>1 Myr), which removed fluid from a widespread area (i.e., several hundred square kilometres) of the basin. The results show that thin parent units, poor lateral continuity of the upper seal, and spatially heterogeneous overpressurisation do not preclude the formation of large dykes.

Unravelling source-to-sink relationships of sediment in coastal regions can be particularly challenging due to a variety of transport directions and mixing within varying local environments in response to sea level fluctuations. Post-glacial sea level rise in the Holocene has resulted in the flooding of former continental margins, locally leading to the separation of islands such as Rottnest in southwest Australia. Rottnest lies approximately 20 km offshore from the mouth of the Swan River, one of the largest permanent river systems across thousands of kilometres of west Australian coastline. In this contribution, we investigate the size, U–Pb age distribution and α-dose values of detrital zircon grains within 13 sand samples collected from three upstream tributaries that drain the Archean Yilgarn Craton, the Swan River estuary, offshore waters surrounding Rottnest Island and modern beaches. We explore sediment derivation, storage and mixing on this passive margin. Carbonate–silicate sands of the region contain detrital zircon with Archean, Mesoproterozoic and Cambro-Neoproterozoic age modes, reflecting regional crystalline basement. Eo- to Paleoarchean zircon grains, including a previously enigmatic >3500 Ma component, are traced from offshore into the estuary, and specifically the Avon River tributary. Detrital mixing models imply an overall fluvial contribution to the estuary and offshore systems of up to 50–65%. By contrast, modern beach samples are dominated by Swan Coastal Plain recycled sediment of up to 96%. The α-dose values of the prominent 3300–3150 Ma age component suggest more efficient fluvial discharge in the Paleo-Swan River than in more recent times. Modern estuary samples have lower average and progressively lower downstream zircon α-dose values, consistent with prolonged chemical and physical reworking and loss of metamict grains with transport distance in the river. We conclude that fluvial drainage networks distribute a locally persistent catchment signal whilst coastal plains in tectonically quiescent settings appear characterized by sediment reprocessing and mixed provenance.

Continental rifts are characterized by up to 30 km wide rotated fault blocks with stratigraphic dip away from the central rift axis. Although gravity-induced mass movements are well known features of collapsed fault block crests, I here demonstrate the occurrence of polymodal gravity-driven mass transport down the back slope of a first-order rift fault block. I identify (1) early sliding related to syntectonic crestal collapse of second-order rift faults, (2) large-scale bed-parallel sliding of the L-M Jurassic sedimentary package, and (3) the accumulation of two 7 km long, 1–2 km wide and up to 750 m thick volumes of complexly slumped material in the hanging walls of two ramp-forming faults. Early sliding is documented by 100 m of repeated Brent Group stratigraphy in a cored well in the study area (well 34/4-15A). These smaller slides have intact internal stratigraphy but show elevated deformation band densities. The seismic data also show evidence for ca. 2 km of massive translational sliding of the ca. 400 m thick and ca. 300 km² large Jurassic section above a lowermost Jurassic bedding-parallel detachment. This translational slide did not deform much internally, except for ductile folding where it slid over underlying active rift faults. Chaotic seismic facies in fault hanging walls are interpreted as contorted Jurassic beds, formed by multiple slumping and sliding events that stacked mobilized sediments into a 750 m thick column. These complex slump volumes occur where fault displacement is highest along two relayed faults. A model is favoured where the large translational slide ruptured with an opening of space against the fault that was progressively filled with slumped material from the footwall. While the large-scale translational sliding only caused moderate internal subseismic deformation, early sliding and, particularly, the complex slumping caused significant internal deformation. This study shows the importance of carefully searching for and distinguishing between different types of mass movement in rift systems.

The McCoy Mountains Formation (McMF) in southern California–Arizona preserves an anomalously thick record of sedimentation during the Mesozoic at a critical time when western North America experienced contrasting tectonic events related to intracontinental rifting along the Mexican Border rift system and consolidation of the North American Cordilleran system. The spaciotemporal interactions among these events and the development of the McCoy basin challenge our understanding of the evolution of the southern extent of North America. At its type locality in the McCoy Mountains, the McMF consists of ~ 7 km of low-grade metasedimentary rocks, originally interpreted as meandering fluvial to alluvial-fan deposits. Uncertainty in the initial timing of sedimentation in the McCoy basin has resulted in multiple tectonic models. We measured ~ 7160 m of detailed stratigraphy and present new sedimentological and detrital zircon results showing that the McCoy basin was occupied by deep-water turbidite systems. These systems deposited an upward-coarsening succession of fine- to coarse-grained detritus during the Cretaceous (ca. 137–70 Ma). Provenance data indicate that the McCoy basin received sediment from Proterozoic basement rocks and metamorphosed Palaeozoic to early Mesozoic sedimentary units. These source rocks are equivalent to the stratigraphy found in the Grand Canyon and Colorado Plateau regions and were likely shed from the southward-advancing Maria fold-thrust belt and possibly the southern Sevier belt in southern Nevada and California. These results, combined with subsidence curves typical of foreland basins, favour deposition within a subaqueous flexural foreland basin system. The presence of a Cretaceous foreland basin this far southwest challenges previously proposed models and suggests that the contractional tectonic regime associated with the North American Cordillera extended into the southwestern most United States during the Early–Late Cretaceous.

The Neogene and Quaternary hinterland basins of the Northern Apennine have been the subject of different tectonic interpretations. Several studies considered these basins as the result of polyphase normal faulting framed in a continuous crustal extensional regime since the middle Miocene. On the contrary, geophysical and geological studies provided evidence of the important role played by out-of-sequence thrusts and backthrusts in the evolution of these basins during a prolongated and intense period of shortening. Here we present an integrated analysis of 2D stacked seismic reflection profiles, stratigraphic and geophysical data from deep exploration wells, gravity data, and published geological and biostratigraphic data for the Valdera-Volterra basin (central Tuscany, Italy). The results support a polyphase and composite evolution of the basin, subdivided into three main phases. During the late Tortonian–Zanclean, the growth of major thrust-related anticlines controlled the evolution of the sedimentary basin. The growth of a syncline determined the creation of accommodation space for the sediments. This main compressional deformation occurred during the Messinian and ended during the Late Zanclean. NE migration of the depocentre during the Early Zanclean was identified, likely possibly due to a differential activity growth between the bordering anticlines. During the Piacenzian, an extensional phase has been recognised, superposed to the previous compressive phase. During the Latest Piacenzian–Early Pleistocene (?), a final compressional phase took place resulting in the positive inversion of the Piacenzian WSW dipping main border fault.

A two-dimensional numerical analysis based on the finite element method and linear elasticity is used to demonstrate how the differential compaction of the basinal unit can cause the early deformation of a prograding and/or aggrading carbonate platform. Our model investigates the modification of the carbonate platform stratal architecture and stress field driven by the process of differential compaction. We compared the results of our model with observations from two Triassic carbonate platforms in the Italian Dolomites: Lastoni di Formin and Nuvolau Mts. (Passo Giau, Italy). We show that the model can explain the modification of stratal architecture, as well as fault and fracture patterns observed on these platforms. In particular, we show that (1) the slope and slope-to-basin transition regions are expected to experience most of the brittle deformation and, differently from what was suggested by previous numerical studies, the formation of platform-ward dipping faults and major fractures with dip angles that tend to decrease moving dip-ward. In addition, (2) the inner platform region can exhibit a slightly tensile regime, which may lead to the formation of syndepositional and/or syndiagenetic fractures. Moreover, (3) in the case of predominantly prograding platforms, the results of the model show a general tilting and thickening of the inner platform strata towards the shelf-slope break.