Liu Bo, Lü Yanfang, Ran Qingchang, et al. Geological conditions and exploration potential of shale oil in Qingshankou Formation, Northern Songliao Basin[J]. 2014, 35(2): 280-285.DOI:
Shale oil and gas is one of the most important resources to replace the conventional oil and gas.According to regional geological surveying
the geological conditions of the development of shale oil in northern Songliao Basin were studied in this paper.Also
the favorable target intervals were selected and their potentials of exploration were assessed.The Qingshankou Formation has obvious cyclicity due to the control of lake level change
with mudstone rich in organic matter and gray matter and silty mudstone appearing alternately.The dark mudstone in the lower subcycle is characterized by large single layer thickness
broad distribution area and high content of organic matter
and is still at the stage of hydrocarbon generation.The upper subcycle is characterized by enrichment of quartz-feldspathic minerals and ultra-low porosity and permeability.Many micro pores and cracks are observed in scanning electron microscope
and they offer reservoir space for oil and gas.In addition
the shale reservoirs in K
1
qn
1
are heterogeneous and mostly have abnormal pressure
thus are favorable for the shale oil accumulation.Geochemical analysis data and isothermal adsorption test of shale interval show that the 1st member of Qingshankou Formation is richest in oil
and contains some gas.So it has the larget exploration potential for shale oil exploration.Based on the above-mentioned geological conditions and oil-gas-bearing possibility study
the space distribution of favorable reservoir in K
1
qn
1
is determined
and the OOIP of shale oil is calculated to be 10.56 billion tons by using probability volume method.