CAJ | 학술논문

根据砂岩普遍薄片、铸体薄片、扫描电镜和其他化验资料等,系统研究柴达木盆地北缘地区鄂博梁Ⅲ号构造的岩石学特征、成岩作用及对孔隙的影响.结果表明:研究区储集砂岩较细,以细砂岩和粉砂岩为主,含少量中砂岩和粗砂岩;岩石类型主要为长石砂岩和岩屑长石砂岩,含少量长石岩屑砂岩.成岩作用主要为压实作用、胶结作用和溶蚀作用,成岩作用阶段已经达到晚成岩阶段A期.压实作用中等是孔隙度大量丧失的主要原因.胶结作用较强,胶结物主要有碳酸盐胶结物、硫酸盐胶结物、硅质胶结和黏土矿物胶结,胶结物充填孔隙、堵塞喉道,在成岩早期能起骨架支撑缓解压实作用的进行.溶蚀作用中等,主要为长石、岩屑、碳酸盐胶结物及杂基等易溶组分溶蚀成粒间、粒内溶蚀孔,为储层增加次生孔隙,属于建设性成岩作用.
근거사암보편박편、주체박편、소묘전경화기타화험자료등,계통연구시체목분지북연지구악박량Ⅲ호구조적암석학특정、성암작용급대공극적영향.결과표명:연구구저집사암교세,이세사암화분사암위주,함소량중사암화조사암;암석류형주요위장석사암화암설장석사암,함소량장석암설사암.성암작용주요위압실작용、효결작용화용식작용,성암작용계단이경체도만성암계단A기.압실작용중등시공극도대량상실적주요원인.효결작용교강,효결물주요유탄산염효결물、류산염효결물、규질효결화점토광물효결,효결물충전공극、도새후도,재성암조기능기골가지탱완해압실작용적진행.용식작용중등,주요위장석、암설、탄산염효결물급잡기등역용조분용식성립간、립내용식공,위저층증가차생공극,속우건설성성암작용.
Based on cast thin section, scanning electron microscopy and laboratory data, a systematic study was conducted on petrology and diagenesis and their effect on the porosity of the reservoir in No.Ⅲ structure of Eboliang area, Qaidam basin. The results show that the study area is of mainly fine sandstone and siltstone, the reservoir granularity is small, the rock types are mainly arkose and lithic arkose with little feldspathic lithic sandstone. The sandstones have suffered from various kinds of diagenesis, such as compaction, cementation and dissolution, reaching the A period of the late diagenetic stage. Compaction effect, of medium degree, mostly accounts for the reduction of prosity. Cementation, being strong, consists of carbonate cement, sulphate cement, siliceous cement and clay mineral. The cements fill up the pore space and block up the throat, but they can resist the running of compaction in the early diagenetic stage. Dissolution is of medium degree and feldspar,debris and carbonate cements have dissolved into the emposieu. Belonging to constructive diagenesis, dissolution increases the secondary porosity.