Combined effects of the subductions of the Pacific Plate and Indian Plate in Central China in the Cenozoic: Recorded from the Wei River Basin

Abstract

The Wei River Basin is located between the Qinling Orogenic Belt and the Ordos Block. It is an important seismic belt and part of the Silk Road in China. The development of the basin is the result of interaction between the Qinling Orogenic Belt and the Ordos Block. Based on the geomorphic features, sedimentary characteristics, and geophysical detection data, combined with the tectonic movement of the Qinling Orogenic Belt in the Cenozoic, this article considers that the Wei River Basin was formed by both the Qinling Orogenic Belt thrusting to the Ordos Block and the left‐lateral strike‐slipping of the margin fault in the Cenozoic. The combined actions of Indian Plate subduction and Pacific Plate subduction have caused the eastern section of the Wei River Basin to turn from east–west to northeast and the Ordos Block to undergo counterclockwise rotation. The analysis of the formation mechanism and evolutionary process of the Wei River Basin should be of great practical significance in the study of the seismicity of the Wei River Basin.

New findings regarding the Fen‐Wei Graben on the southeastern margin of the Ordos Block: Evidence from the Cenozoic sedimentary record from the borehole

“…In the late Miocene–Pliocene, the effect of the uplift of the Qinghai–Tibet Plateau manifested as NE‐directed compression and left‐lateral shear along its northeastern margin, while, at the same time, the lithospheric mantle experienced uplift in eastern China (Ge et al, 2014). Under the combined effects of these two tectonic processes, the Ordos Block tilted westward and rotated counterclockwise (Chen, Wang, & Lou, 2018; Fan et al, 2018; Li et al, 2005; Zhang et al, 2006). During this process, the western Wei River Basin expressed faulted‐depression movement, and the Linfen Basin developed from southwest to northeast.…”

“…The Wei River Basin is a graben‐type basin bounded by a series of faults (Chen, 1984; Cui & Li, 1986; Fan, Chen, & Li, 2018; Han et al, 2002; Li, Zhang, et al, 2018; Xing et al, 2005). The Wei River central fault (F1 in Figure 1), which separates the Ordos Block from the Qinling orogenic belt and controls the spatial distribution of the basin, is a multistage basement fault, as revealed by geophysical and drilling data (Tang et al, 2015).…”

Watershed Topographic Characteristics and Causes Analysis of the Upper Reaches of the Weihe River

“…However, the BTR value is smaller than the southeast margin, with a BTR value of 0.018 (Table 1). This area is not only controlled by the compression of Tibetan Plateau, but also the strike-slip characteristics by Ordos Block (Fan et al, 2018), especially in the northeast of this area (Figure 1a). The Ordos block has reduced and weakened the compression from the Qinghai-Tibet Plateau, so BTR value is low even though its elevation is relatively high in this area.…”

“…Weihe River is the largest tributary of Yellow River, China, originated in Weiyuan County, Dingxi City, Gansu Province and had elevation of 3495 m (Li et al, 2012a). URWR located in the intersection between southwest margin of Ordos block, northern Qinling Orogenic Belt, and southern Liupanshan Mountain (Chen et al, 2018;Fan et al, 2018). The topographic characteristics is mainly controlled by active tectonics (Shi et al, 2018;Zhang et al, 2019).…”

Central China Orogen along the Silk Road (Part 2): Mineral deposits, hydrocarbons, geohazards, and environments

“…In the thematic set on Geohazards , the first paper by Yuan, Ying, et al () is an analysis of geological hazards in the Central China Orogen based on a literature review of published research for more than 5 decades. The paper by Fan, Chen, and Li () focuses on the effects of Cenozoic uplift of the Qinling Orogenic belt as recorded from the Wei River Basin, caused by subduction of the Pacific and Indian plates. The final paper in this section by Chen, Fan, Wang, et al () examines the effects of neotectonic movement of the southern margin of the Ordos Block, as identified in the formation of river terraces.…”