The sedimentary and tectonic evolution of the Yinggehai–Song Hong basin and the southern Hainan margin, South China Sea: Implications for Tibetan uplift and monsoon intensification

Abstract

The Yinggehai–Song Hong basin is one of the world's largest pull‐apart basins, lying along the trace of the Red River fault zone in the South China Sea. South of Hainan Island this basin crosscuts the rifted margin of the northern South China Sea. In this paper we present for the first time a regional compilation of multichannel seismic reflection data from both the strike slip and rifted margins. The basins started to open after ∼45 Ma, especially after ∼34 Ma. The Yinggehai basin was folded and inverted in the middle Miocene, after 21 Ma in the north and 14 Ma in the south, before rapidly subsiding again after ∼5 Ma because of continued tectonism. This subsidence has caused shale diapirism, especially driven by associated sedimentation in the late Pliocene (2.6–2.0 Ma). Extension along the adjacent south Hainan margin shows preferential lower crustal extension, suggestive of lower crustal flow increasing toward the continent‐ocean transition during breakup. Sediment supply is reconstructed to peak in the middle Miocene, then falls between 14 and 10.3 Ma to reach a low in the late Miocene. However, rates rose again in the Pliocene‐Pleistocene. The Red River sediment budget is incompatible with climate models that propose stronger monsoon rains starting at 8 Ma or with large‐scale river capture away from the Red River after ∼10 Ma. Both lines of evidence point to major uplift in the Red River drainage being middle Miocene or older. The recent, preindustrial Red River carried much more sediment than the average Pleistocene accumulation rate, indicating modest sediment buffering onshore, at least in recent geologic time.

Zircon U-Pb geochronology and heavy mineral composition constraints on the provenance of the middle Miocene deep-water reservoir sedimentary rocks in the Yinggehai-Song Hong Basin, South China Sea

“…The depositional environment of the Meishan Formation was interpreted to from littoral to neritic delta facies (Gong et al, 1997 Gong et al (1997), Huang et al (2003) and Gong and Li (2004). 15.5 Ma, and increased between 15.5 and 10.5 Ma (Clift and Sun, 2006;Hoang et al, 2010). The pressure coefficient and geothermal gradient can reach 2.0e2.3 and 4.25e4.56 C/100 m, respectively (Zhang et al, 1996;Huang et al, 2002Huang et al, , 2003.…”

“…The pressure coefficient and geothermal gradient can reach 2.0e2.3 and 4.25e4.56 C/100 m, respectively (Zhang et al, 1996;Huang et al, 2002Huang et al, , 2003. The depocenters are mainly controlled by NW-and roughly N-Strending faults (Sun et al, 2003), which show a migration to the southeastern basin between 21 and 16 Ma, which led to basin inversion and formation of an angular unconformity (Rangin et al, 1995;Clift and Sun, 2006). During 16e5.5 Ma, depocenters gradually migrated back to the northwest, and paused in the northwestern basin ).…”

“…The previous provenance studies have illustrated that the Cenozoic sediments of the Y-SH Basin were from three major source terrains, the southern Yangtze Block (Red River), Indochina Block (central Vietnam) and Hainan Uplift (Gong et al, 1997;Brookfield, 1998;Clift and Sun, 2006;Xie, 2009;Yan et al, 2011;Wang et al, 2014bWang et al, , 2015aCao et al, 2015;Jiang et al, 2015) (Fig. 9).…”

“…2) (Gong et al, 1997;Geng et al, 1998;Gong and Li, 2004). Relatively high temperature and overpressure, rapid subsidence rate, large volumes and diapir structures typify this Cenozoic basin (Zhang et al, 1996;Hao et al, 1998;Huang et al, 2003Huang et al, , 2004Luo et al, 2003Luo et al, , 2009Clift and Sun, 2006;Hoang et al, 2010;Xie et al, 2014). These parameters are also significant for hydrocarbon production in the basin.…”

Late Miocene provenance change on the eastern margin of the Yinggehai-Song Hong Basin, South China Sea: Evidence from U–Pb dating and Hf isotope analyses of detrital zircons

“…For example, Clift and Sun (2006) suggested that the sedimentation rates in the Y-SH Basin increased sharply at the end of the Miocene. Clark et al (2005) used an initiation of the major river incisions to identify the timing of the initial uplift at 13e9 Ma and the high erosion rates between 0.23 and 0.47 mm/yr, and the result does coincide with the thermochronology data published by Xu and Kamp (2000) and Kirby et al (2002).…”