低成熟海相黑色页岩生烃特征的热模拟实验  

Thermal Simulation Experiment on Hydrocarbon Generation Characteristics of Low-mature Marine Black Shale

作　　者：邓模[1,2,3,4] 翟常博 杨振恒[1,2,3,4] 段新国 郑伦举[1,2,3,4] 宋振响 DENG Mo;ZHAI Chang-bo;YANG Zhen-heng;DUAN Xin-guo;ZHENG Lun-ju;SONG Zhen-xiang(Wuxi Research Institute of Petroleum Geology,SINOPEC,Wuxi 214126,China;SINOPEC Key Laboratory of Petroleum Accumulation Mechanisms,Wuxi 214126,China;State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development,Wuxi 214126 China;State Energy Center for Shale Oil Research and Development,Wuxi 214126,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]中国石化石油勘探开发研究院无锡石油地质研究所,无锡214126 [2]中国石化油气成藏重点实验室,无锡214126 [3]页岩油气富集机理与有效开发国家重点实验室,无锡214126 [4]国家能源页岩油研发中心,无锡214126 [5]成都理工大学油气藏地质及开发工程国家重点实验室,成都610059

出　　处：《科学技术与工程》2021年第1期130-137,共8页Science Technology and Engineering

基　　金：国家科技重大专项(2016ZX05061);中国石化重大项目(P16079);中科院先导项目(XDA14010402)。

摘　　要：页岩气是黑色富有机质页岩生烃演化完成后滞留在页岩中的烃类气体,为了查明海相黑色页岩生排烃过程中产物的变化规律及影响因素,揭示海相富有机质页岩的生烃潜力,采用地层孔隙热压生烃模拟仪对四川盆地广元地区上寺剖面大隆组黑色页岩进行热压模拟实验。结果表明:①黑色页岩具有极高的生烃潜力,最高产烃量达452.43 mg/gTOC(总有机碳),其中气态烃总产率195.45 mL/gTOC,液态烃最高产率为377.8 mg/gTOC;②油的产率随热模拟温度升高表现为先升后降的特征,生油演化成峰型尖锐的单峰特征,生油高峰在360℃,甲烷随成熟度升高而增加,而重烃气C2-5则表现为先升后降的特征,甲烷主要由油裂解形成,其次是干酪根热解和重烃气裂解;③气态烷烃呈现δ^(13)C1<δ^(13)C2<δ^(13)C3<δ^(13)C4,且随热模拟温度增加,气态烃的碳同位素值均表现为逐渐富集13C,说明了热模拟过程中只发生了碳同位素的动力学分馏。基于本次热模拟产物产率随热成熟度变化特征,建立了黑色富有机质页岩的生烃模式,分为两个主要阶段:热催化生油气阶段和热裂解生湿气阶段,特别是在很高热模拟温度下仍未进入生干气阶段,表明在过成熟阶段黑色页岩仍具有一定的生烃潜力。研究结果对拓展高过成熟页岩气勘探领域具有较好的参考意义。Shale gas is a hydrocarbon gas retained in black organic rich shale after hydrocarbon generation and evolution.To understand the variation and influencing factors of the products during hydrocarbon generation,and reveal the hydrocarbon generation potential of marine organic rich shale,samples of black shale from Dalong Formation(Upper Permian),Shangsi section in Guangyuan Area,Sichuan Basin were studied by pyrolysis simulated experiment.The results are as follows.firstly,the black shale has extremely high hydrocarbon generation potential,and the highest hydrocarbon yield was 452.43 mg/gTOC(total organic carbon),of which the total yield of gaseous hydrocarbon was 195.45 mL/gTOC,and the highest yield of liquid hydrocarbon was 377.8 mg/gTOC.Secondly,with the increase of pyrolysis temperature,the oil yield rose first and then dropped with the increase of temperature,occurring a sharp single peak of production at 360℃ in evolution.The yields of methane and non-gaseous hydrocarbons showed similar uprising trend with the maturity increase,while heavy hydrocarbon gas C2-5 rose first and then fell,indicating that methane came from oil cracking at beginning,and followed by heavy hydrocarbon gas cracking.Thirdly,the δ^13C of gaseous alkanes exhibited an order of δ^(13)C1<δ^(13)C2<δ^(13)C3<δ^(13)C4,and the carbon isotope values of gaseous hydrocarbons were gradually enriched with 13C as the pyrolysis temperature increases,indicating that the only kinetic fractionation of carbon isotopes occurred during the pyrolysis experiment.Based on the variation characteristics of the pro-duct yield with thermal maturity,the hydrocarbon generation model of black organic rich shale was established.The hydrocarbon generation could be divided into two main stages:thermal catalytic oil-gas generation stage and thermal cracking moisture gas generation stage.In particular,it has not entered the stage of generating dry gas under very high thermal simulation temperature,which indicates that the black shale still has certain hydrocarbon ge

关 键 词：热模拟实验 生烃产率 碳同位素 生烃模式 黑色页岩 大隆组 

分 类 号：TE122.2[石油与天然气工程—油气勘探]