松辽盆地深部上古生界物性特征与典型区勘探实践

Petrophysical Characteristics and Exploration Practice on the Deep Strata of Upper Paleozoic in Songliao Basin

基于前人深层系工作积累以及近年来松辽盆地北部及外围油气地质调查工作进展,本文首先分析了区域地质与地球物理场特征,并针对深层系目的层特点,运用宽频地震、广域电磁法等综合物探手段,研究了松辽盆地西北部的深层系构造地层特征。对松辽盆地及外围地区岩石物性参数进行整理,并总结出不同时代的地层物性特征,重点分析上古生界与上下地层、岩体之间的物性差异。认为该区上古生界二叠系与其上覆的中—新生界、下伏的老地层之间及各类岩体之间存在明显的物性差异,应用地球物理方法研究上古生界分布具备前提条件。在此基础上,阐述了重点目标区重磁电震联合地球物理调查研究进展,尤其是针对深层系开展的宽频地震成像质量较以往地震勘探成果明显提升,获得了更加清晰的物探信息,以及据此部署的地质调查井先后钻遇了深层上古生界二叠系泥质岩层与气测异常。此外,本文还探讨了松辽盆地深层系油气地质调查面临的挑战及未来在岩石物性、综合物探方法研究方面的工作方向。

Based on the accumulation of previous research on deep strata and the progress of oil-gas prospecting in northern Songliao basin and its surrounding areas in recent years,this paper first introduced the characteristics of regional geology and geophysical fields,and then according to the features of the target stratum of deep strata,studied the structural and stratigraphic characteristics of the deep strata in the northwest Songliao basin by comprehensive geophysical prospecting methods such as broadband seismic and wide-field electromagnetic method.The petrophysical parameters of Songliao basin and its surrounding areas were sorted out,and the physical characteristics of strata with different formation ages were summarized,with emphasis on the analysis of the physical differences between the Upper Paleozoic and its upper and lower strata.It is concluded that there are obvious differences in physical properties between the Permian and its overlying Meso-Cenozoic,the underlying strata and various types of rocks in this area,which is the precondition to study the distribution of the Upper Paleozoic by geophysical methods.On this basis,this paper expounds the progress of combined geophysical investigation of gravity,magnetism,electricity and seismic in the key target area.The quality of broadband seismic imaging for the deep strata is significantly improved compared with the previous seismic explorations,and we have obtained clearer geophysical information.According to the above geophysical information,several geological survey wells were deployed,and successively drilled into the argillaceous rocks with anomaly of gas logging in deep Permian.In addition,this paper also discussed the challenges faced by the deep hydrocarbon geological survey and the future research directions in the study of petrophysical properties and integrated geophysical prospecting methods.