Sedimentary architecture of a sandy braided river: Insights from a flume experiment

• DOI: 10.1016/j.petsci.2024.07.016
• Publication Date: 2024-07-19T02:39:50Z
• Authors: Wen-Jie Feng; Gao Fei-Xiang; Chang-Min Zhang; Qi-Hao Qian; Tai-Ju Yin; Tao Lei; Hua-Zhan Guo; Jie Chen
• Keywords: Flume

Sandy braided river deposits are widely preserved in ancient stratigraphic records and act as a significant type of hydrocarbon reservoir. Due to the frequent rapid migration channels within riverbed, sedimentary architecture is highly complex. In this paper, flume experiment was conducted reveal detailed depositional process establish fine model for sandy rivers. The result showed that (1) Three types braid channels, including lateral channel, confluence deep incised were recognized based on geometry, scale, distribution, spatial patterns; they interconnected, forming complex channel network. (2) Braid characterized by migration, abandonment, filling, chute cutoff. Lateral shaped bars dominated formation, growth, reworking bars. (3) Controlled fast variations network, continuously formed, reworked, reshaped, composited multiple accretions with different types, orientations, scales, preservation degrees. Symmetrical asymmetrical presented significantly composition patterns. (4) Dominated continuous temporary limited preserved, account 54.3 percent eventually deposits, four amalgamate patterns recognized. cut only accounting 45.7 deposits. (5) During experiment, 28 near-surface fragmented forms final experimental river; shape, patterns, most observed during largely reworked poorly preserved. (6) scale smaller than from geomorphic observations. aspect ratio width-to-depth also ones measured topography data.