车镇凹陷大王北洼陷成岩作用及孔隙特征研究

Anlyse the Characteristic of Diagenesis and Porosity in Dawangbei Sub-sag,Chezhen Sag

通过对车镇凹陷大王北洼陷的研究,利用大量铸体薄片分析等手段,总结出大王北洼陷的成岩作用类型及特征、所属成岩阶段和成岩演化序列以及孔隙发育特征。车镇凹陷大王北洼陷为近岸水下扇沉积环境,砂体由长石岩屑砂岩,岩屑长石砂岩少量等构成,经历了压实作用、四种胶结作用、长石溶蚀作用等多种成岩作用。根据镜质体反射率(Ro)和粘土矿物混层比随埋藏深度的变化,将车镇凹陷大王北洼陷埋深大于1500m的碎屑岩地层划分为早成岩B、中成岩A期和中成岩B期三个成岩阶段。

Based on the study of the Dawangbei sub-sag in Chezhen sag, using a large number of microscope slide and another analysis methods. Summed up the di agenesis types and characteristic s of Dawangbei su b-sag.Summed up the diagenetic stages and diagenetic sequence of Dawangbei sub-sag. Dawangbei sub-sag in Chezhen sag is nearshore subaqueous fan sedimentary environment. Sand body by feldspathic lithic sandstone and lithic feldspar sandstone small amounts, etc. The rock after compaction, four cementation, Feldspar dissolution and other kinds of diagenesis. According to the Ro and clay mineral mixed layer than along with the change of buried depth, clastic rock strata that up to 1500 m in Dawangbei sub-sag, Chezhen sag are divided into three diagenetic stage： precocious rock phase B, up rock phase A and up rock phase B.