摘要
对东濮凹陷下第三系储层砂岩石英增生边及其中的流体包裹体进行了鉴定和检测 ,结果表明东濮凹陷桥口 -白庙地区共有 3期石英增生现象 ,代表 3期流体活动。第 1期与第2期发生在盆地深陷期 ,当时埋深 1 70 0～ 30 0 0 m,年代 2 8～ 37Ma,第 3期增生边尚不能确定其形成条件 ,但可确定其形成于碳酸盐大规模交代石英颗粒之后。桥口地区第 1期所代表的流体活动温度主要在 1 1 0～ 1 1 5℃ ,第 2期所代表的流体活动温度主要在 1 30～ 1 35℃。白庙地区第1期所代表的流体活动温度主要在 1 0 5～ 1 1 0℃ ,第 2期所代表的流体活动温度主要在 1 2 0～1 2 5℃。这 3期流体活动的性质可能是粘土矿物转化过程中释放的晶格水通过泥岩的幕式压裂作用向砂岩中释放的结果。
Based on a careful observation to the fluid inclusions in quartz overgrowths in the Lower Tertiary reservoirs of the Dongpu Depression, in conjunction with burial history, we have studied the episodes of quartz overgrowths and their reflecting fluid flow. The results show that there are three episodes of quartz overgrowths in the Qiaokou-Baimiao region, Dongpu Depression, which reflect three episodes of fluid flow. The first and second episodes took place in the extensive rifting stage of Dongpu Depression,the burial depth was 1 700~3 000 m, with an age 28~37 Ma. The condition of the third episode of fluid flow in both Qiaokou and Baimiao regions can not be determined due to the technique level, but careful observation to thin sectoins suggests that the third episode took place after the extensive carbonate replacement of quartz and feldspar. In Qiaokou region, the main temperature of the first episode of fluid flow was 110~115℃, while the second episode was 130~135℃. In Baimiao region, the main temperature of the first episode of fluid movement was 105~110℃, while the second episode was 120~125℃. The three episodes of fluid flow may be attributed to the reaction of smectite to illite in mudstones and shales, which interbed with sandstones. The fluid from the reaction of smectite to illite went into sandstones probably through the episodic hydrofarcturing of the overpressured mudstones and shales.
出处
《地质科学》
CAS
CSCD
北大核心
2001年第2期152-163,T001,共13页
Chinese Journal of Geology(Scientia Geologica Sinica)
基金
国家自然科学基金! ( No.4 970 2 0 2 5)
