石油与天然气地质2025，Vol.46Issue(3)：926-943,18.DOI:10.11743/ogg20250315
塔里木盆地深层奥陶系走滑断裂区与非走滑断裂区储层流体超压演化差异特征与成藏机制
Differential fluid overpressure evolution and hydrocarbon accumulation mechanisms of deep Ordovician reservoirs in areas with and without strike-slip faults,Tarim Basin
摘要
Abstract
The deep Ordovician reservoirs in areas with and without strike-slip faults in the Tarim Basin exhibit significant difference in fluid pressure evolution characteristics.Existing exploration practices have shown areas without strike-slip faults hold significant potential for deep hydrocarbon exploration and exploitation.However,there is a lack of systematic studies on the hydrocarbon accumulation and overpressure evolution processes in these areas.In this study,we examine these processes in areas with and without strike-slip faults within the Fuman oilfield based on log data,reservoir characteristics,paleo-pressure reconstruction from fluid inclusions,and the calcite U-Pb isotopic dating.The results are as follows.First,the areas without strike-slip faults in the Tarim Basin underwent three critical pressure evolution stages,namely normal pressure,weak overpressure,and strong overpressure in sequence.On the other hand,the areas with strike-slip faults in the basin also experienced three critical pressure evolution stages:normal pressure,weak overpressure,and normal pressure in sequence.Second,during the Middle-to-Late Caledonian,crude oil charging occurred for reservoirs in these areas,resulting in weak overpressure.In the late stage,numerous pores and fractures are formed in carbonate reservoirs in these areas under tectonic fracturing combined with the dissolution of fluids migrating along faults.The interconnected reservoirs facilitate the redistribution of overpressure within the connected fault systems.As a result,the formation pressure in these areas was gradually reduced to be normal.Third,in the areas without strike-slip faults,the formation pressure increased rapidly to strong overpressure during the Early Yanshanian due to two factors:the lateral migration of deep gas from oil cracking to the Ordovician reservoirs along faults and unconformities and the tectonic compression.The overpressure has been maintained up to now.Fourth,hydrocarbon accumulation in the areas without strike-slip faults followed a sequence characterized by early-stage oil generation,late-stage gas invasion,and lateral adjustment.关键词
流体包裹体/超压演化/U-Pb同位素定年/断控型油气成藏/储层流体/奥陶系/塔里木盆地Key words
fluid inclusion/overpressure evolution/U-Pb isotopic dating/fault-controlled hydrocarbon accumulation/formation fluid/Ordovician/Tarim Basin分类
能源科技引用本文复制引用
薛一帆,赵海涛,黄亚浩,文志刚,刘宇坤,张银涛,乔占峰,罗涛..塔里木盆地深层奥陶系走滑断裂区与非走滑断裂区储层流体超压演化差异特征与成藏机制[J].石油与天然气地质,2025,46(3):926-943,18.基金项目
国家自然科学基金项目(42302154) （42302154）
湖北省自然科学基金青年A类项目(2025AFA106). （2025AFA106）
