库车坳陷迪那2气藏成因类型及成藏机制  

Genetic type and hydrocarbon accumulation mechanism of Dina 2 gas reservoir in Kuqa Depression

作　　者：李峰[1,2] 姜振学[1,2] 李卓[1,2] 杜忠明 

机构地区：[1]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249 [2]中国石油大学(北京)非常规天然气研究院,北京102249 [3]中国海油深圳分公司,广东广州510240

出　　处：《中南大学学报（自然科学版）》2015年第4期1345-1352,共8页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(40972088);国家科技重大专项(2011ZX05003);国家重点基础研究发展计划(973计划)项目(2011CB201105)~~

摘　　要：利用流体包裹体岩相学观察、均一化温度测试、储层定量颗粒荧光分析等手段厘定天然气充注史,应用沉积-成岩-构造一体化预测模型恢复储层孔隙度演化史,并综合天然气充注史与储层孔隙度演化史之间的关系,判识迪那2致密砂岩气藏的成因类型,明确其成藏机制。研究结果表明：迪那2气藏具有＂早油晚气、晚期为主＂的两期油气充注特征,第一期为康村组沉积时（5-12 Ma）的原油充注,第二期为库车组沉积至今（0-5 Ma）的天然气充注;古近系储层具有长期浅埋—短期深埋的特点,储层孔隙度在西域期沉积初期（约2 Ma）降低到10%以下并致密化;迪那2气藏天然气大量充注时间早于储层致密化时间,其成因类型属于＂致密常规气藏＂。认为迪那2气藏具有＂中新世早中期的原油充注、上新世的气侵形成常规气藏、西域期以来的致密常规气藏调整改造再富集＂的成藏过程。The hydrocarbon charging history was determined by observation of fluid inclusion petrological characteristics,homogenization temperature testing and reservoir quantitative grain fluorescence analysis. The porosity evolution of reservior was restored using the model of deposition-diagenesis-structure. The genetic type of Dina 2 tight gas reservoir was identified and its hydrocarbon accumulation mechanism was defined by the relationship of hydrocarbon charging history and reservior porosity evolution history. The results show that Dina 2 gas reservoir has two-stage hydrocarbon charging history. The first stage is mainly charged by crude oil at Kangcun Age（5-12 Ma）. The second stage is mainly charged by natural gas since Kuqa age（0-5 Ma）, which is the main charging stage. Paleogene reservoir has the feature of＂long-term shallow burying and short-term deep burying＂. Reservoir porosity dropped to less than 10% and desificated in the period of Xiyu Age（2 Ma）. The genetic type of Dina 2 gas reservoir is ＂tight conventional gas reservoir＂ because the period of bulk natural gas charging is earlier than that of reservoir desification. In conclusion, hydrocarbon charging process of Dina 2 gas reservoir is established： charged with oil at the early-middle period of the Miocence; charged with gas washing to form conventional gas reservoir in Pliocene; charged with adjustment, modification and re-enrichment of tight conventional gas reservoir in Xiyu period.

关 键 词：库车坳陷 迪那2气藏 致密砂岩气藏 成因类型 成藏机制 

分 类 号：TE122.1[石油与天然气工程—油气勘探]