摘要
在塔中东部局部地区奥陶系碳酸盐岩储集层中发现一期(第Ⅲ期)发强棕红色荧光的烃包裹体,在荧光特征、组分特征上都有其独特性,预示塔中东部成藏的独特性。将这3期对区域成藏有意义的烃包裹体分期进行组分提取、组分分析、相图分析、温度压力分析,分析认为,第Ⅱ期形成于海西运动晚期源于中上奥陶统的正常油得以保存;第Ⅳ期形成于喜马拉雅运动晚期由寒武系原油分解的凝析油气大量充注,使整个塔中地区奥陶系的原油具有中上奥陶统源油和寒武系原油混源特征;第Ⅳ期凝析油气的大规模充注,是塔中地区油气藏普遍存在25-降藿烷系列的原因,也是塔中地区凝析油气藏的重要贡献者;第Ⅲ期形成于燕山-喜马拉雅运动早期源于寒武系高成熟油只在塔中东部地区的中下奥陶统及寒武系充注,这就是只在塔中地区东部发现油藏,而在其他地区主要为凝析油气藏的原因。
A stage（the Stage-Ⅲ） of hydrocarbon inclusion with strong brown-red fluorescence is discovered in the Ordovician carbonate reservoir in eastern Tazhong area,which is different from the other parts of Tazhong area.There are three stages of hydrocarbon inclusions which contributed to the hydrocarbon accumulation in this area.Based on the composition characteristics,phase diagrams,temperature and pressure of them,it is proved that the Stage-Ⅱ inclusion was formed in late Hercynian movement and the oil originated from the Middle-Upper Ordovician was preserved;the Stage-Ⅳ inclusion formed in late Himalayan movement and the large-scale condensate oil-gas charging decomposing from the Cambrian crude allows the Ordovician oil in Tazhong area to be of mixed feature of Middle-Upper Ordovician and Cambrian oils.This stage condensate charging is the reason for prevalent existence of 25-lower hopane series in oil reservoirs in Tazhong area as the great contributor;and the Stage-Ⅲ formed in Yanshan-early Himalayan movement and high-maturity oil from the Cambrian only accumulated in the Middle-Lower Ordovician and Cambrian reservoirs in eastern Tazhong area,which explains the normal oil reservoir can be found in the eastern Tazhong,while condensate reservoirs have been mainly found in the other areas of Tazhong.
出处
《新疆石油地质》
CAS
CSCD
北大核心
2011年第3期267-271,共5页
Xinjiang Petroleum Geology
关键词
塔里木盆地
奥陶系
烃包裹体
组分
相图
压力
Tarim basin
Ordovician
hydrocarbon inclusion
composition
phase diagram
pressure
