Provenance, Depositional Facies and Favorable Reservoir Distribution of the Lower Cretaceous Yageliemu Formation in the Kuqa Depression, Tarim Basin, NW China

Abstract Tectonic movements and related depositional responses are always complicated in a typical foreland basin. This study investigates the provenance and depositional facies of the Cretaceous Yageliemu Formation in the Kuqa Depression, Tarim Basin, NW China, to determine favorable reservoir distribution. Evidence from detrital zircon U–Pb age and heavy mineral assemblages illustrates two mainly provenances: (1) the Kelasu River characterized by the U–Pb age from 220 to 400 Ma and 420 to 560 Ma and the heavy mineral assemblages of leucoxene, zircon, and barite; (2) the Kuqa River dominated by the U–Pb age from 300 to 520 Ma and the heavy mineral assemblages of barite and apatite. Integration of core, well logging curves, and seismic responses indicates that the Yageliemu Formation can be subdivided into three parasequence sets: EL2, EL1, and LL1. The parasequence sets of EL2 and EL1 are favorable for the development and accumulation of large-scale sand bodies. The sediments in the Yageliemu Formation mainly consist of pebbly sandstone, coarse- to fine-grained sandstone, siltstone, and silty mudstone deposited in a braided-river delta front setting. The braided-river delta front subfacies can be divided into subaqueous distributary channels, proximal mouth bar, and distal mouth bar microfacies. Based on paleogeomorphology reconstruction, seismic attribute facies and core observations, depositional facies and distribution of favorable reservoir facies in the EL1 and EL2 intervals is predicted. This study innovatively identifies two distinct provenance systems, establishes a high-resolution sequence stratigraphic framework, reconstructs the source-to-sink paleogeomorphic configuration, and proposes a hierarchical favorable reservoir prediction model for the Yageliemu Formation. It deepens insights into sedimentary responses of compressional foreland basins and guides ultradeep tight gas exploration in the Kuqa Depression.