摘要
继四川盆地、塔里木盆地发现大量的海相原油裂解气气田之后,在渤海湾、柴达木等陆相盆地也发现存在陆相原油裂解气,但目前对陆相原油裂解气的生气机理、主控因素以及与海相原油裂解气差异性研究还不够。采用封闭体系黄金管热模拟实验方法,选取陆相原油样品开展裂解模拟实验。结果表明:(1)陆相原油在高演化阶段可以大量裂解生气,陆相纯原油系列主生气期对应的R_(O)值为1.7%~3.3%;(2)砂岩介质下的原油主生气期对应的R_(O)值为1.7%~2.6%,对陆相原油裂解有催化作用;(3)陆相原油裂解分为3个阶段,R_(O)=0.9%~1.6%时为原油初步裂解阶段,R_(O)=1.6%~2.1%为原油大量裂解阶段,R_(O)=2.1%~4.2%为原油裂解衰竭阶段;(4)纯原油与砂岩介质下的原油碳同位素随温度升高呈现相似的变化规律,乙烷与丙烷碳同位素值均在原油裂解衰竭阶段出现倒转。随着勘探向深层发展,陆相原油裂解气藏的发现会越来越多,因此,深入研究陆相原油裂解气的生气机制和产气特征对寻找和发现规模陆相原油裂解气田(藏)具有重要指导作用。
A large number of marine crude oil cracking gas fields have been found in Sichuan and Tarim basins,and continental crude oil cracking gas has also been found in Bohai Bay and Qaidam basins.However,there is not enough research on the mechanism of continental crude oil cracking gas,the main contR_(O)lling factors and the difference between continental crude oil cracking gas and marine crude oil cracking gas.In this paper,a closed system gold tube pyR_(O)lytic experiment was used to simulate the pyR_(O)lysis of continental crude oil samples.The results show that:(1)Continental crude oil can generate a lot of pyR_(O)lytic gas in the high thermal evolution stage,and the R_(O)value corresponding to the main gas generation period of continental pure crude oil series is1.7%-3.3%.(2)The R_(O)values corresponding to the main gas generation period of sandstone media series are1.7%-2.6%,which can catalyze the cracking of continental crude oil.(3)There are three stages in the pR_(O)cess of continental crude oil cracking:the initial cracking stage is when R_O=0.9%-1.6%,the massive cracking stage is R_O=1.6%-2.1%,and the exhaustion stage is R_O=2.1%-4.2%.(4)Carbon isotopes of pure crude oil under the medium of pure oil and sandstone show similar changes with the increase of temperature.Carbon isotopes of ethane and pR_(O)pane are reversed in the late stage of crude oil cracking.With the development of deep exploration,more and more continental oil cracking gas reservoirs will be found.Therefore,it is important to study the gas generation mechanism and gas pR_(O)duction characteristics of continental crude oil cracking gas to find and discover large-scale continental crude oil cracking gas fields or reservoirs.
作者
陈大伟
李剑
国建英
李志生
郝爱胜
齐雪宁
CHEN Da-wei;LI Jian;GUO Jian-ying;LI Zhi-sheng;HAO Ai-sheng;QI Xue-ning(University of Chinese Academy of Sciences,Beijing 100049,China;Research Institute of Petroleum Exploration and Development,PetroChina,Beijing 100083,China;Key Laboratory of Gas Reservoir Formation and Development,CNPC,Langfang 065007,China)
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2021年第4期518-528,共11页
Natural Gas Geoscience
基金
国家科技重大专项(编号:2016ZX05007)
中国石油股份有限公司科技项目(编号:2019B-0601)
中国石油股份有限公司科技重大专项(编号:2018E-11-02)联合资助。
关键词
陆相原油裂解气
砂岩介质
黄金管模拟实验
Continental crude oil cracking gas
Sandstone medium
Gold pipe simulation experiment
