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Although volcanism is an important process in the evolution of rift basins, current tectono‐sedimentary models largely neglect its impact on sediment supply, transport pathways, and depositional systems. In this paper, we integrate core, well logs, and 3D seismic data from the Palaeogene‐Neogene Shaleitian (SLT) uplift and surrounding sub‐basins, Bohai Bay Basin, China, to investigate the sedimentology and geomorphology of a volcanic rift basin. Results of this study show that the spatial distribution of extrusive centres was strongly controlled by basement‐involved intra‐basin normal faults. During the early part of the syn‐rift stage, the SLT uplift supplied sediments to transverse fan deltas and braided‐river deltas that fringed the adjacent syn‐rift depocentres. Volcanic deposits mainly occurred as relatively thin lava flow and pyroclastic facies that partially filled fault‐controlled topographic lows, reducing topographic rugosity, and enhanced breaching of basement highs between syn‐rift depocentres. Integration of drainage to the syn‐rift depocentres and development of through‐flowing axial depositional systems was enhanced. During the later part of syn‐rift and in early post‐rift stages, the SLT uplift was progressively inundated, reducing sediment supply to the fringing transverse depositional systems. In contrast, axial braided‐river deltas became the main depositional systems, sourced by large hinterland drainage from the Yanshan fold‐belt to the northwest. Volcanism in the late syn‐rift and early post‐rift occurs as thick lava flow and pyroclastic facies that infill rift topographic lows and locally blocked axial fluvial systems creating isolated lakes. Within hanging wall depocentres, volcanic topographic highs split and diverted axial fluvial and deltaic systems. Furthermore, volcanism supplied large volumes of volcanic sediment to the rift resulting in increased sedimentation rates, and the development of unstable subaerial and subaqueous slopes and deposits, increasing the occurrence of landslides. Based on the observations of this study we update tectono‐sedimentary models for rift basins to include volcanism. [ABSTRACT FROM AUTHOR]

Liaodong Bay Depression is a strike‐slip basin with complex tectonic movement that lead the source‐to‐sink (S2S) systems evolution vary greatly in temporal and spatial characteristics. This study explored the sedimentary characteristics, dispersal patterns, and pathway formation in Liaodong Bay Depression, as well as their controlling factors. We selected more than 10 pathways with north‐west and north‐east directions in Liaoxi Sag in the western part of Liaodong Bay Depression, a typical strike‐slip bet controlled graben, to investigate their S2S system distribution. By combining seismic data, we divided the strike‐slip fault bends into three stress setting parts, namely, a central restraining bend, which is the fault translation part, and two releasing bends in the southern and northern of fault terminals. As the heavy mineral assemblage and clay content in the west side of Liaoxi Sag differs from that in the east side, we put forward an S2S index to show the sediment transport distance according to the data we have obtained. Using this index, we recovered the dispersal pattern and pathway development and speculated on the sedimentary provenance. In the restraining bend, we recognized that the pathways mainly show a symmetrical "V" or "W" shape with unclear erosion boundaries and were dominated by filling processes. Considering the heavy mineral assemblage data, we also found that the sediment provenance area decreased and the sediment provided direction transferred from the two‐side provenance to one. Combining the fast sedimentary rate calculated with clay content data, the S2S systems in this area were steep–wide–deep systems and a wide and shallow system. In the releasing bend, the pathways show an asymmetrical "V" or "W" shape and a clear erosional boundary. As shown by the heavy mineral assemblage data, the sediments from these areas mainly have a west side provenance and were deposited in the proximal area. Thus, the S2S system in this area is a kind of steep–deep system. Then, the investigation by integrated of tectonic movement and S2S geomorphic statistical parameters revealed that the elevation height of the S2S is a key factor in control pattern development. The various evolution patterns within the two different stress settings provide insights into the formation process of the S2S developed in a strike‐slip tectonic belt. [ABSTRACT FROM AUTHOR]

This paper investigates the reservoir characteristics of deep-water lacustrine-delta sandstones in the Upper Triassic Yanchang Formation in the western Ordos Basin, north-central China. The Yanchang Formation has previously been interpreted as a shallow-water lacustrine deltaic succession, and this interpretation has been used to guide petroleum exploration activities which have however met with only limited success. The present study integrates thin-section, wireline log, X-ray diffraction and SEM data from wells in the western Ordos Basin to determine the sedimentary and diagenetic characteristics of sandstones in the C6 and C4+5 sub-members of the Yanchang Formation, and to interpret the units' depositional environment. The C6 and C4+5 sub-members in the study area are composed of: mudstones and fine-grained sandstones, which are interpreted as deep-water pro-delta deposits; laterally-extensive sand sheets (outer delta-front deposits); and small-scale distributary channel and mouth bar sandbodies (inner delta-front deposits). The sandstones have reservoir potential but diagenesis has had a range of effects on reservoir quality. Compaction together with cementation by calcite and clay minerals including chlorite and kaolinite may have affected pore throat geometry and permeability adversely. However dissolution of feldspars and calcite cement created secondary porosity. Hydrocarbon accumulations may occur in delta-front channel and mouth bar sandbodies. Core studies show that some sandstone intervals have relatively good reservoir properties with porosity up to 15% and permeability up to 9mD. [ABSTRACT FROM AUTHOR]

The article presents a study which aims to determine the Cretaceous shallow- water delta in the Songliao Basin, China. The study suggests that the shallow-water deltas were developed commonly in lake basins under a comparatively stable tectonic setting, shallow water depth, gentle slope having low subsidence rate, a frequently fluctuating lake level, open lake basin characteristics and sufficient sediment supply.