塔里木盆地中上奥陶统碳酸盐岩层序格架及其对礁滩体的控制

 以露头和钻井资料为基础,结合层序地层学、生物地层学及沉积学理论,建立了塔里木盆地中上奥陶统碳酸盐岩层序格架,并探讨层序与礁滩体发育之间的关系.研究表明,中上奥陶统发育5个3级层序,其中塔中地区的良里塔格组3个3级层序可进一步划分为7个4级层序,塔中的良里塔格组中上部与塔北地区的桑塔木组多为同时异相关系,可见塔中与塔北良里塔格组为一明显的穿时地层单元;塔中良里塔格组共发育5期礁滩体,高频层序对礁滩体发育具有很好的控制作用,对礁滩储层预测有指导意义.

Tarim Basin Middle-upper Ordovician Carbonate Strata Sequence Framework and Its Control of Reef Beach Body

Based on the outcrop and drilling data, using the sequence stratigraphy, biostratigraphy and sedimentary theory, the Tarim Basin middle-upper Ordovician carbonate strata sequence framework and the relations between the sequence and the reef-shoal development are established. It is shown that the middle-upper Ordovician develops 5 third-grade sequences. The 3 third-order sequences of Lianglitage Formation in Tazhong area can be further divided into 7 fourth-order sequences, and the middle-upper Lianglitage Formation in Tazhong area and the Sangtamu Formation in Tabei area are contemporaneous heterotopic facies, so the Lianglitage Formation in Tazhong and Tabei is obviously a diachronism stratigraphic unit. The Liangligeta Formation in Tazhong area develops 5 periods of the reef beach body, the high-frequency sequences can well control the reef beach body development and is of great significance for the later reel-flat reservoirs prediction.