中文摘要：

随着油气勘探向深部发展．在深部寻找优质储层是一个亟待深入研究的问题。永进地区位于准噶尔腹部中石化中部3区块，勘探目的层埋藏深，大于5000m，储层多为低孔-特低孔低渗-特低渗储层，因此，在该地区深部寻找相对优质储层具有重要的理论意义和勘探意义。该地区发育区域性不整合，即J／K不整合。在不整合形成期间．大气淡水具有高的流速和相对开放的流体环境，可以溶蚀易溶矿物并将溶蚀产物带离出溶蚀区：颗粒包壳可以抑制石英加大和碳酸盐矿物沉淀，保存原生孔隙和形成的次生孔隙；永进地区油气充注早，早期的油气充注改善了流体成岩环境，抑制胶结作用，同时，其携带的有机酸溶蚀易溶矿物，产生次生孔隙，油气早期充注从两个方面改善储层。

英文摘要：

With the development of the petroleum industry, looking for high-quality reservoirs at depths becomes a problem that must be studied intensively. The Yongjin area is one of the three blocks in the interior of the Junggar basin explored by the Sinopec. The exploration target in the Yongjin block is deeper than 5000 m, in which most reservoirs have low and very low porosity and permeability. So looking for relatively high- porosity and -permeability reservoirs in the block is important. Regional unconformity between the Jurassic and Cretaceous is well developed. During the formation of the unconformity, meteoric water, which has a high flow rate and a relatively open fluid environment, dissolved minerals and carried the dissolution product out of the dissolution area; grain coats inhibited quartz enlargement and carbonate precipitation and conserved primary pores and secondary pores; in the Yongjin block hydrocarbon filled earlier and the earlier hydrocarbon filling improved the diagenetic environment of the fluids and restrained cementation; on the other hand, organic acid in the hydrocarbon dissolved more soluble minerals and generated secondary pores. All those together can preserve and improve the porosity of deeply buried reservoirs of sandstone in the Yongjin block, Junggar Basin.