Petrophysical characteristics of Huoshiling Formation from CCSD SK-2 in the Songliao Basin of Northeast China

The Continental Scientific Drilling Project in the Songliao Basin was aimed at solving a series of scientific problems involved in Cretaceous paleoclimate and paleoenvironmental research, the development of deep exploration techniques, and the earth's deep resource survey. As the main borehole of the scientific drilling project of Songliao Basin, SK-2 has collected continuous and in-situ geophysical log data. In this paper, geophysical log data were used to reveal the range of petrophysical parameters of rocks in Huoshiling Formation. Combined with laboratory core NMR test analysis, the authors studied the pore structure characteristics of different igneous reservoirs. The results show that the Huoshiling Formation mainly consists of andesite, tuff, complex conglomerate and tuff mudstone. The igneous facies are dominated by the explosive facies and the effusion facies. The andesite and complex conglomerate are characterized by high resistivity and low acoustic wave time difference. The characteristics of the tuff are low resistivity and high acoustic time difference, and the tuff mudstone has the lowest resistivity. The reservoir has the characteristics of low porosity and low permeability, but the tuff reservoir has developed small and medium pores and has relatively good physical properties, and hence it is a favorable reservoir. The research results provide strong support for further evaluation of deep oil and gas resources and stratigraphic structure in the Songliao Basin.