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The science of the provenance, sedimentary system, and distribution of sand bodies is unclear, limiting oil and gas exploration. Here, we combined heavy mineral, rare earth element, petrographic, and outcrop data to shed new light on the provenance, depositional environment, and paleoclimatic conditions of the Permian Jiamuhe Formation. The provenance is characterized by “a main provenance system, and four provenance zones,” and this result could be interpreted from analyses of its seismic reflection, clastic composition, REES, and heavy minerals. A detailed sedimentological study performed in the excellent outcrops, a comprehensive analysis of logging, and the legalistic cores of this formation allowed for the identification of ten lithofacies and three lithofacies associations. Four distributary/underwater channels were observed. Furthermore, the redox and paleoclimatic conditions based on trace elements (Th/U, V/(V + Ni), V/Cr, Cu/Zn, Sr/Ba, and Sr/Cu) suggested a weak reduction in the environment, as well as semi-humid and semi-dry conditions of the Jiamuhe Formation. These conditions are also supported by the mudstone color and plant fossils. The tectonic setting belongs to the acid island arc area based on the trace element discrimination diagram of La-Th-SC and the values of the La, Ce, ΣREE, L/H, La/Yb, and (La/Yb)N criteria. The research results further confirm that there are differences in the mineral compositions in the same provenance area, and they provide a geological basis for the fine sedimentary facies characterization and a favorable zone prediction in this area.

Majority of the oilfields in the Hongshanzui region are small and complex fault block reservoirs, and the evolution of the sedimentary system under the sequence stratigrapic background has been a controversial topic. Six middle-term base-level cycles were divided, and eight types of lithofacies assemblages were recognized based on the stacking patterns and volumetric partitioning according to the core, well logs, and seismic data correlated with the field investigation of outcrops. Furthermore, the evolution of the sedimentary system under the sequence stratigraphic framework was clarified. Among the six middle-term base-levels, MSC1 belongs to the retrogradational system tract, and the sediment distribution exhibits the characteristics of "large plain and small front." MSC2 belongs to the transgression system tract, and the sediment distribution exhibits has the characteristics of "small plain and large front." In the case of MSC5 and MSC6, the sediment distribution exhibits the characteristics of "dominant channel and repeated channel-switching." Further, the controlling factors of tectonic, base level, climate, and minerals are discussed.This research has been applied to the exploration and development of the Hongshanzui oilfield, and a certain benefit has been achieved. • Sequence-stratigraphic framework is constructed. • Filling and sedimentary models are established. • The base-level were controlled by alicyclic and autocyclic processes. • The controlling factors of the sedimentary evolution of early-middle Jurassic were discussed. [ABSTRACT FROM AUTHOR]