Pore Structure Characteristics and Influencing Factors of Tight Reservoirs Controlled by Different Provenance Systems: A Case Study of the Chang 7 Members in Heshui and Xin’anbian of the Ordos Basin

The evaluation of pore structure is critical in understanding reservoir characteristics. This study aims to analyze the microscopic characteristics tight reservoirs from various provenances through physical property analysis, casting thin sections, scanning electron microscopy (SEM), and constant−rate mercury injection. throat parameters Chang 7 were analyzed compared those Xin’anbian Heshui areas. results show that intergranular pores dominate type area, followed by feldspathic dissolution pores, with high-necked tubular content caused weak compaction dissolution, respectively. On other hand, feldspar a high tube−bundle throats flake−bent flake compaction. difference between two blocks minimal, but significant. Under same permeability conditions, radius distribution range samples area narrower than tiny contributing significantly permeability. Sedimentary hydrodynamic conditions diagenesis are primary reasons for differences throats, reservoirs.