松辽盆地莺山断陷营城组凝灰熔岩微观孔隙特征

打开文本图片集

中图分类号：P588.1;P618.13 文献标志码：A

Abstract：The tuff lava of the Yingcheng Formation in the Yingshan fault depression of the Songliao basin is characterized by ultra-low porosity and low permeability. In order to characterize the nanometer to micron multiscale reservoir space and evaluate qualitatively and quantitatively，the factors influencing tuff lava reservoir development in the Yingcheng Formation are discussed. Based on core observation and thin section identification，combined with FE-SEM，LTNA，HPMI， CPMI，and NMR，the micropore characteristics of the Yingcheng Formation tuff lava were characterized qualitatively and quantitatively at multiple scales.The results show that：The tuflava of the Yingcheng Formation is mainly composed of vitric debris and rhyolitic debris. The reservoir space types are mainly devitrification pore， feldspar dissolved pore，and ilite intercrystaline pore. A great number of secondary pores and fissures are formed during the devitrification process，and provide about 66.8% of pore volume，which is vital to improving the reservoir physical properties.

Key words： tuff lava; microstructure; pore type; reservoir; Yingcheng Formation; Yingshan fault depression;Songliao basin

0 引言

盆地发育早期通常伴随着强烈的火山活动，凝灰岩作为普林尼式火山活动的主要产物，在我国的多个含油气盆地深层均有发现[1-2]。（剩余14929字）