塔北、塔中奥陶系碳酸盐岩异常高压形成、保存与分布  

Formation,Preservation and Distribution of Abnormally High Pressure in Ordovician Carbonate Rocks in Northern and Central Tarim Basin

作　　者：段永贤 宋金鹏 郇志鹏 杨连刚 周鹏 吕端川 田志宏[1] DUAN Yongxian;SONG Jinpeng;HUAN Zhipeng;YANG Liangang;ZHOU Peng;LV Duanchuan;TIAN Zhihong(PetroChina Tarim Oilfield Company,Exploration Department,Korla,Xinjiang 841000,China;PetroChina Tarim Oilfield Company,Oil and Gas Field Productivity Construction Department,Korla,Xinjiang 841000,China;PetroChina Tarim Oilfield Company,Research Institute of Exploration and Development,Korla,Xinjiang 841000,China;PetroChina Tarim Oilfield Company,Resource Exploration Department,Korla,Xinjiang 841000,China)

机构地区：[1]中国石油塔里木油田分公司勘探事业部,新疆库尔勒841000 [2]中国石油塔里木油田分公司油气田产能建设事业部,新疆库尔勒841000 [3]中国石油塔里木油田分公司勘探开发研究院,新疆库尔勒841000 [4]中国石油塔里木油田分公司资源勘查部,新疆库尔勒841000

出　　处：《新疆石油地质》2023年第4期421-428,共8页Xinjiang Petroleum Geology

基　　金：中国博士后科学基金(2022M712952)。

摘　　要：塔里木盆地奥陶系超深层碳酸盐岩储集层受控于高能相带、区域不整合面及多期次和多类型断裂破碎作用改造,内幕流体及压力系统分布异常复杂。分析认为,沉积、构造、化学反应等因素均影响了塔北、塔中地区奥陶系碳酸盐岩异常高压的形成、保存与分布。厚层膏盐岩延缓了烃源岩热演化,阻滞应力传递,不整合面为构造应力和欠压实压力传递、晚期油气充注提供通道,均有利于异常高压形成;后期硫酸盐热化学还原反应一定程度上削弱了异常高压的发育程度并影响其垂向分布层位;厚层泥岩、致密石灰岩等优质盖层有利于异常高压保存。异常高压主要分布于生烃坳陷周缘、远离主干断裂或活动性较弱的次级断裂。其中,塔北地区异常高压主要由构造挤压与欠压实作用形成,呈多点散状分布于断裂复杂的跃满地区和鹿场地区;塔中地区由流体膨胀形成的异常高压集中分布于塔中10号构造带,储集层一般规模较小且定容。The Ordovician ultra-deep carbonate reservoirs in the Tarim basin are controlled by high-energy facies belts,regional unconfor-mity surfaces,and multi-period and multi-type fault fragmentation and reforming,as a result,the distributions of internal fluid and pressure systems are extremely complex.According to the analysis,factors such as sedimentation,structure,and chemical reaction affect the forma-tion,preservation,and distribution of abnormally high pressure in the Ordovician carbonate rocks in the northern and central Tarim basin.Thick gypsum-salt rocks delayed the thermal evolution of source rocks and blocked stress transfer,while the unconformity surfaces provid-ed pathways for the transfer of structural stress and undercompaction pressure,and for the late hydrocarbon charging,all of which are con-ducive to the formation of abnormally high pressure.The later thermochemical reduction reaction of sulfate weakened the development of abnormally high pressure to a certain extent and affected the vertically distributed layers.High-quality caprocks such as thick mudstone and tight limestone are conducive to the preservation of abnormally high pressure.The abnormally high pressure is mainly distributed around hydrocarbon-generating depressions and at secondary faults far away from primary faults or with weak activity.In the northern Tarim basin,the abnormally high pressure is mainly resulted from tectonic compression and undercompaction,and it is scattered as multi-ple points in the Yueman and Luchang areas with complex faults.In the central Tarim basin,the abnormally high pressure due to fluid ex-pansion is concentrated in the TZ-10 structural belt,where the reservoirs are generally small in scale and constant in volume.

关 键 词：塔里木盆地 奥陶系 碳酸盐岩 异常高压 成因机制 分布规律 走滑断裂 断控储集层 

分 类 号：TE122[石油与天然气工程—油气勘探]