中南大学学报（自然科学版）2013，Vol.44Issue(6)：2402-2409,8.
酒泉盆地营尔凹陷下白垩统异常高压成因及模拟
Origin and modeling of overpressure in Lower Cretaceous of Ying'er sag, Jiuquan Basin, northwest China
摘要
Abstract
Ying'er sag of Jiuquan Basin develops overpressure in Lower Cretaceous.The compaction and overpressure were analyzed by using pressure direct measurements,wireline log and transformation of clay minerals data.To test the analyzed origins of overpressure,pressure modeling by the fluid-flow method was performed.The results show that there are four pressure zones vertically,i.e.hydrostatic regime (＜2.5 km),shallow overpressure regime (2.5-3.2 km),pressure transition regime (3.2-3.6 km) and deep overpressure regime (＞3.6 km) and the overpressure decreases from south to north taking Changshaling as the dividing line.The primary cause of overpressure is disequilibrium compaction resulted from late rapid subsidence since Miocene.The observation that the rapid conversion of smectite to illite coincides with the overpressure regimes is interpreted to the direct contribution of transformation of clay minerals to overpressure.Limited by the abundance of organic matter (w(TOC)＜l.5％) of overpressure zones,the hydrocarbon generation contributes little to overpressure.Different mechanical and chemical fluid-flow pressure models were performed and compared.The modeled pore pressure and porosity evolution by mechanical compaction combined with chemical compaction are consistent with the observation results and more reasonable,which suggests that disequilibrium compaction and chemical compaction are the main causes of overpressure in Ying'er sag.关键词
营尔凹陷/异常高压/成因机制/化学压实Key words
Ying'er sag/ overpressure/ development mechanism/ chemical compaction分类
能源科技引用本文复制引用
周一博,柳广弟,钟佳倚,刘庆顺,于豪..酒泉盆地营尔凹陷下白垩统异常高压成因及模拟[J].中南大学学报（自然科学版）,2013,44(6):2402-2409,8.基金项目
国家重点基础研究发展计划("973"计划)项目(2007CB209503) （"973"计划）
