百重7井区三叠系克上组主产油层储层特征研究

Studies on Features of Main Productive Reservoir of Trias Upper Kelamayi Formation in №7 District of Baizhong

通过大量岩心铸体薄片及物性等资料,对准噶尔盆地百重7区三叠系克上组主产油层储集层的岩石学特征、孔渗特征及孔隙类型等进行了深入研究,分析影响储层储集性能的主要因素,并对研究区主产储层进行分类评价。结果表明:主要勘探目的层克上组油层组砂岩储层岩石类型主要为岩屑砂岩,长石岩屑砂岩;岩石成分成熟度低;结构成熟度中等偏低;颗粒分选中等偏差;圆球度以次棱一次角为主;颗粒间接触形式以线和点一线接触为主;经历了压实、胶结、溶解等作用;孔隙类型以粒间孔、粒间溶孔、粒内溶孔为主。碎屑组成、粒级、填隙物含量和成岩作用均对储层性能有重要影响。研究区储层分为三大类,克上组油层组砂岩储层多为Ⅰ类、Ⅱ类储层。优质含油储集体多出现在分支河道发育部位。因此,加强沉积微相研究,努力寻找分支河道发育的地带成为下一步勘探的重要思路。

According to core mould thin section and physical properties data,the article studied the petrological features, porosity, permeability features and pore types of main productive reservoirs of Upper Kelamayi Formation in No. 7 District in Baizhong oilfieid, Junggar Basin, and analyzes the main factors that influent the capacity of reservoirs, also made an evaluation on main reservoirs classified. The results show that the rocks of sandstone reservoirs of Upper Kelamayi Formation, the target strata for exploration, are dominated by lithic sandstone, feldspathie lithic sandstone. The maturation of ingredients of rocks is lower. The maturation of texture of rocks is medium or slightly lower. The grains have good sorting, roundness is dominated by sub--edge --sub--corner, the contacting ways between grains,dominated by linear contact and point--linear contact, The rocks have undergone compression,cement and dissolution etc. and the porosities are dominated by intergranular pores, intercrystal pores and all kinds of emposieu. The components of clast ,grain size grade ,contents of fillings and diagenesis may have important influences on the perform--ante of reservoirs. The reservoirs in the area studied can be divided into three types and the sandstone reservoir of Upper Kelamayi Formation are dominated by type Ⅰ , Ⅱ reservoir. Qualified petroleum reservoirs distribute in the part where branch channel develops.Therefore, to enforce the studies on sedimentary micro--facies and try best to search for the area where the branch channel develops is an important thinking for next explo- ration.