Geological conditions for shale oil formation in the fourth member of Funing Formation of Eocene series in Jintan Basin
This study evaluates the unconventional oil and gas exploration potential of the Cenozoic residual basins in southern Jiangsu,focusing on Jintan Basin.Utilizing a range of data sources,including drilling records,core analyses,logging data,and laboratory tests from Well-J9,we extensively analyzed the geological features of the fourth member of Funing Formation.These analyses encompass rock mineral composition,sedimentary characteristics,organic geochemical properties,and reservoir qualities.Findings indicate that the fourth member of Funing Formation was deposited in a semi-closed to closed saline sedimentary environment,predominantly characterized by shallow to semi-deep lakes.This member is marked by substantial mud shale thickness(exceeding 250 m in deep concave zones),low organic matter abundance(average total organic carbon(TOC)of 1.02％),and a moderate degree of thermal evolution(vitrinite reflectance(Ro)ranging from 0.81％to 0.85％),providing a fundamental basis for shale oil hydrocarbon generation.Additionally,the presence of fractures and porous shale reservoir spaces,coupled with a high content of brittle minerals,suggests favorable conditions for the development of complex fracture networks during subsequent fracturing interventions.Considering the oil and gas shows in existing boreholes,it is posited that the fourth member of Funing Formation,particularly near the Maoshan tectonic push-over zone,holds medium to low maturity shale oil exploration potential in southern Jiangsu.
Jintan Basinthe fourth member of Funing Formationshale oilgeological conditionslow-medium maturity
万方数据
维普
