Basin Research最新文献

Sequence stratigraphy has long provided a framework for deciphering how environmental conditions are recorded in sedimentary basins across a range of tectonic settings. Much of our current understanding of sequence architecture in depression basins, however, comes from studies that focus on individual external forcings such as sediment supply, climate, or lake-level change. The relative importance of these forcings in shaping key characteristics of stratigraphic patterns remains poorly quantified. Moreover, distinguishing external signals from autogenic variability is particularly challenging at mid-term (10⁵–10⁶ yr) timescales. To address these issues, we conducted nine numerical simulations of continental-scale sediment-routing systems, spanning millions of years, to examine how basin sedimentation and sequence stratigraphy respond to variations in lake level, precipitation and tectonic uplift within the source region of a depression basin. Our results show that different external forcings dominate distinct aspects of stratigraphic development: (1) precipitation strongly governs depositional and erosional rates, whereas uplift exerts only a minor influence; (2) uplift determines the overall extent of the basin margin, while autogenic processes introduce local spatial variability in its position; and (3) lake-level cyclicity controls stratal stacking patterns. A reduction in amplitude results in an earlier development of the initial flooding surface, which in turn extends the duration of transgression and increases the regressive ratio. Across all simulations, enhanced precipitation produces short, thick stratigraphic packages, whereas tectonic uplift generates more elongated, thin successions. These findings highlight the distinct signatures of different external forcings in shaping stratigraphic development and provide a basis for interpreting environmental signals preserved in continental depression basins, particularly over mid-term timescales.

Major thickness changes of the Namurian interval (Serpukovian and early Bashkirian) recorded in wells across several basins in northwestern Europe provide indications for rifting, but little is known about the dynamics of this extensional phase. On the basis of new biostratigraphic analyses, well-log correlations, seismic interpretations, and geological models for the Campine Basin (northeastern Belgium), this study is the first to provide detailed constraints on the timing and geometry of this middle Carboniferous tectonic phase. The karstification of the lower Carboniferous carbonates, which is key for geothermal and gas storage applications in the region, was strongly influenced by the middle Carboniferous tectonics, highlighting the importance of a thorough understanding. During the early to late Visean, the Campine Basin was characterised by carbonate platform development under relative tectonic quiescence. The latest Visean was a time of major shifts in tectonics throughout Western Europe and marked the start of differential subsidence of the eastern Campine Basin. In this part of the basin, a several hundred meters thick sediment succession was deposited, with a progressive increase in siliciclastics at the expense of carbonates. In the western Campine Basin, in contrast, the latest Visean and earliest Namurian represented a major depositional hiatus. As differential subsidence continued from the Visean into the Namurian up to the earliest Westphalian A (late Bashkirian), the contemporaneous depositional sequences, mainly delta-systems, were consistently developed thicker in the eastern Campine Basin compared to the western Campine Basin. The regional thickness model of the Namurian, on the basis mainly of seismic data, indicates that the differentiation between the western and eastern Campine Basin took place along a narrow basin margin comprised of tilted blocks and faults with normal vertical throws having predominantly NNE–SSW orientations. This fault direction could have resulted from an ESE–WNW extensional direction that likely originated from N-S maximum horizontal compression by the northwards migrating Variscan thrust front further south. The extensional phase ended in early Westphalian A and marked the start of a thermal subsidence phase that likely continued up to the late Westphalian B when compressional foreland dynamics gradually started dominating the region. This transition from extension to thermal subsidence coincided roughly with a regional change in sedimentary deposition from delta progradation towards lower delta plain deposition.

Organic maturation and clay mineral-based estimates of the maximum paleotemperatures experienced by the Precambrian/Cambrian sediments on the East European Craton (EEC) are in disagreement. To resolve this conflict and reconstruct thermal histories of these sedimentary rocks we used three low-temperature thermochronometers: zircon and apatite (U–Th)/He (ZHe, AHe) and apatite fission track (AFT) methods, complemented by AFT modelling of thermal histories. At the cratonic edge (Podillya), the ZHe ages are partially reset, implying that the AFT ages are fully reset, and that the maximum paleotemperatures were in the range of 160°C–200°C, similar to earlier estimates based on the degree of illitization of smectite. Comparison with analogous data for the overlying Silurian bentonites identifies the edge zone of the former Devonian/Carboniferous Variscan foreland basin. In the Podillya region the modelling of thermal history of the Cambrian/Ediacaran strata indicated exhumation in Carboniferous time. In the cratonic interior (Volyn, Belarus, and Lithuania), the AFT ages are totally or partially reset, implying the maximum paleotemperatures close to 120°C, which confirm earlier estimates based on the degree of illitization of smectite, but are higher than the estimates based on the organic geochemistry. The relatively short mean confined tracks lengths (13.6 ± 0.4 to 10.8 ± 0.4 μm), and their varied standard deviation values (2.1–0.9) indicate slow exhumation within the partial annealing zone.

Mass-transport complexes (MTCs), the deposits of submarine slope failures and common features of sedimentary basins worldwide, can act as effective seals for hydrocarbons and carbon sequestration due to shear-induced overcompaction. However, seal failure is occasionally observed in specific parts of MTCs, leading to hydrocarbon and carbon dioxide leakage and posing potential threats to seabed stability. In this study, we combine 3D seismic and well log data from Qiongdongnan Basin, northern South China Sea, to investigate the mechanisms that influence and control the seal potential of MTCs. We identified three vertically stacked MTCs overlying a gas hydrate bearing interval. Seismic interpretation reveals that MTCs seal tends to fail in intervals where MTCs overlies the frontal ramp or remnant block, whereas the remaining intervals effectively seal the underlying gas hydrate. Petrophysical analyses show that MTCs intervals overlying frontal ramps or remnant blocks exhibit significantly lower density and velocity, higher porosity and permeability, indicating reduced compaction in these intervals. Numerical simulations indicate that during MTCs emplacement, shear localisation normally develops in the lowermost part, forming a narrow (10%–20% MTCs total thickness), highly deformed basal shear zone. However, shear localisation is disrupted by the remnant block or frontal ramp, leading to low shear strain and thus low seal potential in MTCs intervals overlying the remnant block or frontal ramp. Therefore, we propose that shear localisation is a key mechanism controlling the seal potential of MTCs. Disruption of this process during emplacement can significantly compromise MTCs seal potential, with important implications for understanding hydrocarbon distribution and for assessing the feasibility of submarine carbon sequestration using MTCs as natural seals.

The permanent oceanic connection between the Jurassic Central Atlantic and the Cretaceous South Atlantic was only established with the late opening of the Equatorial Atlantic, but the timing of this event remained unclear due to a lack of geological dating. In 2023, the DIADEM oceanographic cruise conducted sampling of the Buteur Ridge, offshore French Guiana, by dredging and during a manned deep submersible (Nautile) dive. The Buteur Ridge belongs to the eastern rifted margin of the Demerara Plateau, formed during the Lower Cretaceous Equatorial Atlantic rift. It is a 7 km-long and 6 km-wide tilted block, located at a depth of 3750 m, where sedimentary records of the Equatorial Atlantic are outcropping, making it an ideal location for investigating the timing of this rift.

We integrate petrological observations, biostratigraphy, fission-track analyses of detrital apatites and zircons, and LA-ICP-MS U–Pb dating of authigenic apatites to reconstruct the sedimentary, diagenetic and thermal history of the sediments sampled on the Buteur Ridge.

Our results constrain the tectono-sedimentary evolution of the divergent margin of the Demerara Plateau, revealing a complex rifting history of the Equatorial Atlantic involving two distinct rifts. The onset of the first rift occurred between 130 and 125 Ma (Hauterivian), which is earlier than the previously proposed Aptian age. A second rifting then occurred during the Cenomanian, likely during the kinematic reorganisation between Africa and South America in the Equatorial Atlantic. This later rifting is evidenced on the Buteur Ridge by terrigenous sedimentation followed by telodiagenesis during basin inversion, likely related to normal fault reactivation and ridge uplift. We interpret the crystallisation of authigenic apatites, dated 93 ± 12 Ma, as a record of the subsequent onset of marine transgression at the end of this second rifting, likely not occurring after the Late Cenomanian (circa 93 Ma).

Washover fans form during intense storms through barrier breaching and coastal inundation. Despite their importance for understanding coastal response to storms and their potential as stratigraphic traps, ancient washover fans remain poorly documented and underrepresented in subsurface studies, resulting in limited criteria for their recognition. This study investigates the depositional characteristics, controls, and dispersal patterns of a tectonically controlled washover fan succession within the late Eocene Pinghu Formation, Xihu Depression, using 3D seismic, geological and geophysical logs, and petrology. Based on palaeogeography, heavy mineral analysis, seismic-based provenance analysis, and paleocurrent studies suggest that the Pinghu Formation records a barrier island system. Successions of washover fan deposits are tens of meters thick and comprise stacked 0.5–2.0 m (locally up to 6.6 m) thick, medium- to fine-grained sandstone beds. Individual sandstone beds are generally poorly sorted, normally graded, contain gravel lags, and exhibit parallel stratification. Grain-size distributions and spatial trends from different wells support a marine-to-landward transport process. Petrology shows abundant dolomite crystals and bioclasts. The washover fan deposits are interbedded with thoroughly bioturbated mudstone intervals, which are interpreted as back-barrier bay deposits. These successions are significantly different from those of river-dominated deltas and flood-tidal deltas present in the study area. Washover fan development and preservation are controlled by sea-level fluctuations, sediment supply, and antithetic faults with associated paleo-uplifts. The fan dispersal pattern was confined to the syn-rift period and coincided with rapid sea-level rise. This study provides criteria for the identification of ancient washover fans and enhances our understanding of their development. Additionally, owing to the succession's significant stratigraphic trap potential, this study is a useful reference for petroleum exploration in the East China Sea Shelf Basin and analogous basins.