为了认清鄂尔多斯盆地富县探区三叠系延长组长6段有利储层的分布规律， 通过大量的岩石薄片和铸体薄片的镜下鉴定，并结合扫描电镜、阴极发光、X-衍射等测试结果，研究了该区长6油层组主要成岩作用及其对物性的影响，指出主要成岩作用类型有压实作用、胶结作用和溶蚀作用；由于压实作用损失的孔隙度为18.78%，由胶结作用损失的孔隙度为9.16%，由于沥青充填损失的孔隙度为5.12%，而各种溶蚀作用却使孔隙度增加了5.12%，造成现今平均孔隙度为9.49%。

The paper is aimed at making clear the distribution of the favorable reservoirs in the area. Based on core description, cast section, popular section, scanning election microscope, x-ray diffraction etc, it is believed that the main diagenesis types are pressure solution, cementation and dissolution. The primary porosity of the reservoir rocks is 37.17%, which is reduced by 18.78% by compaction and pressure solution and 9.16% by cementation, and 5.12% by asphalt-filling. The secondary pores are produced by organic acids' dissolving organic matter at maturing stages, resulting in an increase of porosity by 5.38%. The preserved average porosity is 9.49% at present.