准噶尔盆地腹部地区深埋储层物性特征及影响因素

准噶尔盆地腹部地区的储层埋深一般大于4 300 m,部分地区深度可达6 000 m左右,孔隙度和渗透率的大小变化范围也较大,弄清物性的主控因素有利于深埋储层的预测,为勘探提供依据.本文在前人研究和分析化验资料的基础上研究了该区深埋储层的物性,由于岩石类型多为岩屑砂岩,岩石成分含较多的塑性岩屑,因此强烈的压实作用极大的降低了准噶尔盆地腹部地区深埋储层的孔隙度,晚期的含铁碳酸盐岩胶结物使岩石更加致密.早期的碳酸盐岩胶结物因后期的有机酸和大气淡水的溶解作用产生了较多的次生溶蚀孔隙,晚期生烃导致的超压及早期油气充注对储层成岩过程中的成岩作用具有抑制作用,在一定程度上改善了深部储层物性,为深部油气的聚集提供了有利空间.

DOMINANT FACTORS AFFECTING THE RESERVOIR PROPERTIES OF DEEPLY BURIED BED IN THE CENTER OF JUNGGAR BASIN

In the center of Junggar basin,reservoirs develop generally at about 4300m,and in some area it is 6000m,and the porosity and permeability are distinctly different.Therefore,making clear what effects the characters of deeply buried reservoir is important for forecasting favorable targets and gives some good advice for prospecting for oil and gas.On the basis of prior work and analyzing information,this paper studies the reservoir characters of Junggar Basin.Because the reservoir mainly consist of Lithic sandstone and the component are more plasticlast,compaction consumingly reduces porosity;at the same time,latter ferroan carbonate in sandstone more compact.However,hydrocarbon and meteoric water dissolve early carbonate and produce many secondary porosity,and overpressure producing by hydrocarbons generation and emplacement of hydrocarbons distinctly restrain diagenesis of reservoir,which is benefical to preserve secondary porosity and properties of deeply buried reservoir,and offer favorable accumulated space for deep oil and gas.