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Two hundred and eighty-one samples, collected from drilling core NS93-5 located in the Nansha area of the South China Sea, were used to study the magnetic characteristics of the sediments in the sea. Detailed rock magnetic results show that the magnetic minerals of the sediments were dominated by ferrimagnetic minerals such as magnetite, and a small contribution of hematite and maghematite also existed. The sediments recorded three negative values of remanence magnetic inclination at the depth: 191 206 cm, 232 248 cm, and 292 308 cm. The corresponding ages of these negative values were 65.87 68.7 ka B.P., 73.4 80.8 ka B.P. and 108.4 113.6 ka B.P., respectively, according to stratigraphy of oxygen isotope, ¹⁴C, and the age of a volcanic ash layer. The negative value during 108.4 113.6 ka B.P. may be the record of a Blake event in the sediments of the Nansha area.

Sediment mass volumes for periods since the Oligocene (E₃, N₁¹, N₁², N₁³, N₂, and Q) in the South China Sea (SCS) were calculated on the basis of geological and geophysical data including ODP borehole data. Above the pre-Oligocene base, the estimated sediment volume is 7.01×10⁶ km³ and the mass is 1.44×10¹⁶ t for the entire SCS, with an average sedimentation rate of 6.22 cm/ka and accumulation rate of 12.8 g/(cm² · ka) since the Oligocene. Most of the sediment was deposited on the continent shelf and slope, while only 5% of the total mass accumulated in the Central Basin. Sediment basins on shelf and slope occupy 34% of the entire SCS area bounded by the 2 000 m thickness contour, but receive more than 82% of the total sediment mass, indicating that sediment basins played a central role of sedimentary process in the SCS. The highest sedimentation rate and the largest mass volume occurred in the Oligocene SCS, which is quite different from global sedimentation rate patterns. Therefore, we conclude that deposition in marginal seas was primarily controlled by local tectonics.

An extra-thick high-quality brown coal was found to have accumulated in the Xianfeng basin in Yunnan Province, China. There are also abundant sedimentary marks of allochthonous genesis in the extra-thick coalbeds. These genesis indicators reveal a new submodel about allochthonous accumulation, which is: the long-distance river transportation of detrital plant and inorganic matter!?the sedimentation of detrital plant fan delta+the hypautochthony accumulation of local lakeshore swamp peat!?the autochthonous accumulation of local lacustrine peat+the sedimentation of fine inorganic matter!?the mixing and transportation by flood current or weak storm flow or underwater gravity flow!?the mechanical differentiation and their resedimentation between detrital plant and inorganic matter. This submodel can be called the double accumulation of lacustrine detrital plant fan delta and underwater gravity flow  or Xianfeng submodel , which supplements the allochthonous-hypautochthony lacustrine combination accumulation model  of the extrathick coalbeds. The combination accumulation model is based on the Fuxin submodel and Fushun submodel in the Chinese Mesozoic and Cenozoic intarcontinental fault basin.

The Qinshui basin in southeastern Shanxi Province is an important base for coalbed methane exploration and production in China. The methane reservoirs in this basin are the Carboniferous and Permian coals. Their thickness is strongly controlled by the depositional environments and the paleogeography. In this paper, sedimentological research was undertaken on the outcrop and borehole sections of the Taiyuan and Shanxi formations in the Qinshui basin and the basin-wide lithofacies paleogeography maps for these two formations have been reconstructed. The Taiyuan Formation is composed of limestones, aluminous mudstones, siltstones, silty mudstones, sandstones, and mineable coal seams, with a total thickness varying from 44.9 m to 193.48 m. The coal seams have a thickness ranging between 0.10 and 16.89 m, averaging 7.19 m. During the deposition of the Taiyuan Formation, the northern part of the basin was dominated by a lower deltaic depositional system, the central and southern parts were dominated by a lagoon environment, and the southeastern corner was occupied by a carbonate platform setting. Coal is relatively thick in the northern part and the southeastern corner. The Shanxi Formation consists of sandstones, siltstones, mudstones, and coals, with the limestones being locally developed. The thickness of the Shanxi Formation is from 18.6 m to 213.25 m, with the thickness of coal seams from 0.10 to 10 m and averaging 4.2 m. During the deposition of the Shanxi Formation, the northern part of the Qinshui basin was mainly dominated by a lower deltaic plain distributary channel environment, the central and southern parts were mainly an interdistributary bay environment, and the southeastern part was occupied by a delta front mouth bar environment. The thick coals are distributed in the central and southern parts where an interdistributary bay dominates. It is evident that the thick coal zones of the Taiyuan Formation are consistent with the sandstone-rich belts, mainly located in the areas of the northern lower deltaic plain and southeastern barrier bar environments, whereas the thick coal zones of the Shanxi Formation coincide with the mudstone-rich belts, located in the areas of the central and southern interdistributary bay environments.

This paper considers the lithospheric rheological structure of the East Qinling orogenic belt to explore its geodynamics. The lithospheric rheological structure was calculated by the constraints of the lithospheric temperature str

The features of the faults in the central and northern Tibetan plateau are discussed, based on two super-wide band magnetotelluric (MT) sounding profiles belonging to the INDEPTH (III)-MT project, which were finished between 1998 a