Reservoir characteristics and factors influencing shahejie marl in the shulu sag, bohai bay basin, eastern China

Shahejie marl in the Shulu Sag is a crucial resource for unconventional hydrocarbon exploration China. Although breakthroughs have been made tight oil this area, mechanisms underlying formation of reservoir and factors controlling its ‘sweet spots’ not thoroughly studied. To understand pore structure characteristics influencing reservoir, we analyzed core samples from Wells ST1 ST3. A series experiments was conducted on samples, such as X-ray diffraction, focused ion beam scanning electron microscopy, micro-CT, total organic carbon test. Additionally, physical properties different rock fabrics were studied with auxiliary tests, mercury intrusion capillary pressure analyses, nuclear magnetic resonance, porosity permeability thin-section observation. The results revealed that characterized by low (1.61%) (2.56mD). (1.61% 3.26mD) laminated better than those (0.92% 1.68mD) massive marl. Clay minerals quartz content (11.8 8.2%) less (16.2 13.3%). pores include intercrystalline pores, dissolution microfractures. primarily distributed along dark lamina, good connectivity. few isolated uniform holes observed Influenced fabric mineral composition, layered fractures mainly developed marl, while structural main type microfractures primary sedimentary mechanism geological action differences fabric; affects which are key to be considered when searching spots’. Particular attention should paid these during development similar basins.