Architectural Model of a Dryland Gravel Braided River, based on 3D UAV Oblique Photogrammetric Data: A Case Study of West Dalongkou River in Eastern Xinjiang, China

Abstract

Three-dimensional unmanned aerial vehicle (UAV) oblique photogrammetric data were used to infer mountainous gravel braided river lithofacies, lithofacies associations and architectural elements. Hierarchical architecture and lithofacies associations with detailed lithofacies characterizations were comprehensively described to document the architectural model, architectural element scale and gravel particle scale. (1) Nine lithofacies (i.e., Gmm, Gcm, Gcc, Gci, Gcl, Ss, Sm, Fsm and Fl) were identified and classified as gravel, sand and fine matrix deposits. These are typical depositional features of a mountainous dryland gravel-braided river. (2) Three architectural elements were identified, including channel (CH), gravel bar (GB) and overbank (OB). CH can be further divided into flow channel and abandoned channel, while GB consists of Central Gravel bar (CGB) and Margin Gravel bar (MGB). ( 3) The gravel bar is the key architectural element of the gravel braided river, with its geological attributes. The dimensions of GBs and their particles are various, but exhibit good relationships with each other. The grain size of GB decreases downstream, but the dimensions of GB do not. The bank erosion affects the GB dimensions, whereas channel incision and water flow velocity influence the grain size of GB. The conclusions can be applied to the dryland gravel braided river studies in tectonically active areas.

A seismic prediction method of reservoir brittleness based on mineral composition and pore structure

“…Jimusaer Sag is located in the southeast edge of the Junggar Basin, surrounded by Qitai uplift, Santai fault, Xidi fault and Jimusaer fault, which is in the form of a dustpan high in the east and low in the west. The Lucaogou Formation has developed throughout the entire depression, with an average thickness of about 200-350 m (Figure 1) (Yin et al, 2022;Yin et al, 2023a;Yin et al, 2023b). It belongs to the sedimentary system of saline lake basins, characterized by mixed carbonate clastic volcanic gypsum rocks, integrated source and reservoir, thin layer stacking, and dispersed desserts.…”