摘要
塔里木盆地古城地区寒武系存在热液活动且白云岩的岩石学、地球化学特征表明其受到了热液的影响,但热液活动与储层形成之间的关系以及储层的分布特征尚不明确。根据寒武纪岩相古地理和台缘带丘滩体岩石学特征的综合分析,认为古城地区寒武统白云岩为浅埋藏白云岩化作用成因,热液的作用方式是后期改造,发育热液改造型白云岩储层。镁同位素分析表明,鞍形白云石沉淀所需的镁离子主要来自于寒武系本身,热液流体先对白云岩进行溶蚀,层内富集镁离子后再发生白云石沉淀。综合测井、岩心资料,通过计算强热液改造段与待预测井段的测井响应之间的协方差距离,实现了城探1井热液改造强度的单井预测。与三维地震资料相结合,实现了上寒武统各期丘滩体等时地层格架的热液改造强度的平面预测。结合热液流体对储层的差异改造,预测了不同储集性能的热液改造型储层的平面分布。
Two stages of hydrothermal occurred in the Cambrian carbonate of Gucheng area, Tarim Basin and thepetrologic and geochemical characteristics of the dolomite indicate that it was influenced by hydro- thermal;however, the relationship between hydrothermal activities and the formation of dolostone reservoir and the distribution of the reservoir were not well studied yet.According to the characteristics of Cambrian- lithofacies paleogeography and platform margin petrology,it suggests that the dolomitization occurred dur- ing shallow burialstage,the action mode of hydrothermal is late-stage reformation, further indicating that the type of reservoir is hydrothermal reformed reservoir.Based on the ways of hydrothermal influence on reservoir,it shows that the reservoir type can be named as hydrothermal-reformed dolostone reservoir. Magnesium isotope analysis shows that the magnesium ions needed for saddle dolomite are mainly from Cambrian itself. Hydrothermal first dissolved the Cambrian dolostone and enriched magnesium ions and then precipitated dolomite locally. Based on logging and core data, with the calculation of covariance dis- tances between logging values,the hydrothermal reforming intensity of Well CT 1 was predicted.Combined with 3D seismic data,the distributions of hydrothermal reforming intensity in plane were obtained. Com- bined with the differences of different hydrothermal reformation,the distribution of hydrothermal reformed reservoir with different qualities was predicted.
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2017年第6期939-951,共13页
Natural Gas Geoscience
基金
国家科技重大专项(编号:2011ZX05004-001)
中国石油天然气股份有限公司重大科技专项(编号:2014E-32-01)联合资助
关键词
热液改造型储层
储层形成机制
热液改造强度
分布预测
Hydrothermal reformed reservoir
Formation mechanism of reservoir
Hydrothermal reforming intensity
Distribution prediction
