中文摘要：

利用岩心、岩石薄片、铸体薄片,扫描电镜和X衍射观察分析数据,结合前人研究成果,对鄂尔多斯盆地西南部长6砂岩储层岩石学特征进行研究,并对不同区块的岩石学特征进行对比分析。结果表明：该区岩石以岩屑长石砂岩和长石砂岩为主;石英、长石含量较高,岩屑、填隙物含量较低,成分成熟度较低;岩屑以变质岩岩屑为主,塑性岩屑含量较高,刚塑性岩屑相对含量变化具有明显的方向性;分选性中—好,颗粒以次棱角为主,结构成熟度相对较高,各小区块岩石学特征有所差别;物源和沉积环境的不同是该区域岩石学特征的重要影响因素。

英文摘要：

Using core,rock thin section, cast thin section,scanning electron microscope and X dif-fraction analysis data, combined with previous research results, we studied the petrological character-istics of long 6 sandstone reservoir in Longdong area of Ordos Basin. And the petrological characteris-tics of different blocks were compared and analyzed. The results show that the main rock types of this area are lithic feldspathic sandstones and feldspar sandstones. Quartz, feldspar content is high, detri-tus ,interstitial material content and compositional maturity are low. The interstitial material is mainly of metamorphic detritus, and the plastic detritus content is high. The change of relative content of rig-id -plastic debris has obvious orientation ; Sorting is medium - well, particle is main of sep - angu-lar, structure maturity is relatively high. Petrological characteristics of each cell block are different.The difference of provenance and sedimentary environment is the important factor for the petrologic characteristics.