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The Application of Rasc/Casc Methods to Quantitative Biostratigraphic Correlation of Neogene in Northern South China Sea
Published in Wang Naiwen, J. Remane, Stratigraphy, 2020
For the northern shelf of the South China Sea, Neogene was the period of thermal subsidence after extensive rifting and continental sedimentation in Paleogene. In Late Oligocene the shelf broke up, the South China Sea basin began to form, and the transgression on the northern shelf started. The strata of Late Oligocene and Neogene in the area consist of entirely marine sediments, mainly mudstone, siltstone, and sand-stone of coastal plain, deltaic, and neritic facies, with less amount of reefal limestone (Fig. 2). The lower section of Neogene contains mainly benthic foraminifera, suggesting a relatively shallow water. Since Late Miocene the area became an open sea, as indicated by abundant planktonic fora-minifera and calcareous nan-nofossils. Fossil records indicate that the area was mostly in the subtropic zone with warm and humid climate, except in Late Oligocene to early Early Miocene when the area was relatively cool and dry. There were three major sedimentary cycles, with transgression climax occurring in late Early Miocene, middle Late Miocene, and Early Pliocene. Sand bodies formed at the beginning of transgressions and the ending of regressions, as well as reef buildups formed in shoaling areas are good reservoirs for hydrocarbon, and transgressional mudstones are good caps [5, 11].
A preliminary Pb-Pb and U-Pb study on the MVT ore deposits in the Cambrian of Hunan (South China)
Published in Adam Piestrzyński, Mineral Deposits at the Beginning of the 21st Century, 2001
M. Boni, F. Lapponi, J. Schneider, Th. Bechstädt, W. Liu, R. Zheng
In the upper Lower Cambrian (Longwangmiao age), the tectonic regime at the southeastern border of the Yangtze plate passed from rifting to thermal subsidence and the passive margin evolved towards a complex system of carbonate platforms, ramps and slopes (Ye & Pu 1990). The platform-margins and slope facies have been grouped into the Qingxudong Fm (Fig. 1).
Fluvial sequences and basin development in the northern Galilee Basin
Published in Australian Journal of Earth Sciences, 2018
The thick development of sequence 1 and lack of a transitional systems tract indicates relatively rapid subsidence and high sediment load infill of the basin (Figure 21). The models of Flemings and Jordan (1989) indicate that moderate rates of thrusting and sediment supply are factors that produce basinal patterns as shown by isopachs representing the Jericho Formation. The rapid thinning onto the Hopkins and Belyando thrusts shows that these features were active during deposition. Evidence of contemporary uplift along the Bingeringo Thrust System suggests a series of piggy-back thrusts to the east were involved (Van Heeswijck, 2010). These uplifts reflect an increasing rate of crustal convergence that commenced during the Kanimblan Orogeny. This convergence is also reflected in the development of the Natal Formation of the underlying Drummond Basin. The lack of forebulge shown in the model indicates continued influence of thermal subsidence on the basinal architecture. Red beds throughout the unit indicate a dry climate. The lack of conglomeratic facies suggests that sediment flux was low with a moderate transport coefficient. Petrofacies analysis shows that the quartzose Lake Galilee Sandstone has a predominantly cratonic source, while the lower Jericho Formation has a greater input from proximal volcanic and thrust belt sources in the Anakie Inlier and Drummond Basin to the east (Van Heeswijck, 2006). The dissimilar petrofacies of the Lake Galilee Sandstone indicates that it represents an axial drainage system in an underfilled basin that sourced the majority of its sediment load from an uplifted craton to the northwest. No evidence of contemporaneous volcanism is contained within sequence 1 or by correlative foreland-basin sediments in the adjacent Bowen Basin. During sequence 1, broad-scale flexural subsidence of the foreland depocentre produces an accommodation that is filled by erosion of the thrust highland and platform hinterland. Similar but offset depositional trends for the underlying Natal Formation of the Drummond Basin indicate tectonic comparability for these two intervals of the basinal succession. The hiatus suggested by previous authors (Day, 1976; Draper, 1997; Gray, 1976, 1977; Gray & Swarbrick, 1975; Olgers, 1972) is likely to be an artefact of imprecise biostratigraphic control.