The differentiation of gravity flow deposits across depositional environments has gained increasing recognition. This investigation focuses on the Wuliyasitai sag in the Erlian Basin to elucidate subaqueous gravity flow systems within small lacustrine rift basins. Through integrated analysis of core, well-log, and 3D seismic data, the sedimentary features, genetic types, and controlling mechanisms of gravity flows have been investigated. Two distinct sedimentary architectures are identified: microlenticular thin beds and mounded thick deposits, comprising thirteen lithofacies grouped into nine lithofacies associations. Microlenticular units originate from slide-triggered gravity flows, exhibiting composite deposition from slide-slump, sandy/muddy debris flows, and turbidity currents. It also involves hybrid beds formed through flow transformation from sandy debris flows and turbidity currents to muddy debris flows. Mounded units represent flood-generated gravity flows dominated by bedload processes, displaying proximal-to-distal facies transitions from gravelly debris flows through sandy debris flows to turbidites. Spatially, slide-induced deposits occur as dispersed accumulations within the steep slope zone's nosing structures, whereas flood-derived deposits form short-tongued geometries in the gentle slope's mid-inner zones. Key depositional signatures include coarse-grained lithologies, poor sorting, debris flow predominance, and limited flow transformation efficiency in gravity flow deposition of small lacustrine fault basins. Basin configuration, sediment supply, structural framework, and subaqueous topography collectively govern gravity flow development in such fault-controlled lacustrine systems. Basin background, source supply, basin structure, and subaqueous topography collectively govern gravity flow development in such lacustrine basins.
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