地质科技通报2025，Vol.44Issue(5)：13-28,16.DOI:10.19509/j.cnki.dzkq.tb20240159
塔里木盆地富满油田FI17走滑断裂带奥陶系原油地化特征、充注差异及其控制因素
Geochemical characteristics,charging differences,and controlling factors of the Ordovician crude oil in the FI17 strike-slip fault zone of the Fuman Oilfield,Tarim Basin
摘要
Abstract
[Objective]The Fuman Oilfield has significant potential for oil and gas exploration,and is a key area for increased oil reserves and production in the Tarim Oilfield.Analyzing the source,thermal maturity,and charging process of crude oils in this area is essential for understanding the hydrocarbon accumulation patterns,enrichment laws,and guiding future exploration activities.[Methods]Based on systematic organic geochemical analysis of 15 crude oil samples and fluid inclusion samples from three wells,as well as the orientation segmentation and active phases of the strike-slip fault,this study examines the geochemical characteristics of crude oils,hydrocarbon charging processes,and their main controlling factors in the FI17 strike-slip fault zone.[Results]The results show that the crude oil in this fault zone is derived from the Lower Cambrian Yurtus source rocks.The equivalent vitrinite reflectance value of the crude oil,calculated from aromatic parameters,ranges from 0.80%to 1.20%.The crude oil has undergone relatively weak thermal chemical sulfate reduction(TSR),gas stripping,and oil cracking.The fault zone and its periphery have experienced three stages of oil charging with different maturities:Late Caledonian,Late Hercynian,and Himalayan periods,and the gas charging occurred during the Himalayan period.However,there are differences in oil maturity within the same period between the northern and southern segments.The northern and middle segments are mainly dominated by oil contributions from the second stage(blue-green fluorescence)and third stage(bright-blue fluorescence),however,the southern segment is predominantly charged by the second-stage oil with bright-blue fluorescence and the Himalayan-period gas invasion altering pro-existing oil.The FI17 strike-slip fault zone exhibits a north-to-south increasing gradient in the oil thermal maturity,gas stripping intensity,oil cracking degree and contribution of late-stage hydrocarbons.[Conclusion]This spatial variation is governed by fault activity intensity that intensifies southward,which is stronger in the south and weaker in the north.This study suggests the likely presence of deeper,late-stage high maturity hydrocarbons in the northern and middle sections of the fault zone,and the current exploration depth has not yet reached the lower limit of liquid hydrocarbon occurrence.Therefore,deeper reservoirs still have significant potential for oil and gas exploration.关键词
富满油田/流体包裹体/油气成藏/原油裂解/走滑断裂/塔里木盆地Key words
Fuman Oilfield/fluid inclusion/petroleum accumulation/oil cracking/strike-slip fault/Tarim Basin分类
天文与地球科学引用本文复制引用
王清华,蔡振忠,平宏伟,张银涛,刘瑞东,杨美纯,鲁中灯,杨鑫,张新乐..塔里木盆地富满油田FI17走滑断裂带奥陶系原油地化特征、充注差异及其控制因素[J].地质科技通报,2025,44(5):13-28,16.基金项目
国家自然科学基金项目(42072176 （）
42272169) （）
