压力对有机质生烃演化作用的研究进展  

Studying Advances in Effect of Pressure on Organic Matters Maturation

作　　者：何春民 李腾飞[1] HE ChunMin;LI TengFei(State Key Laboratory of Organic Geochemistry,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院广州地球化学研究所有机地球化学国家重点实验室,广州510640 [2]中国科学院大学,北京100049

出　　处：《沉积学报》2018年第5期1040-1048,共9页Acta Sedimentologica Sinica

基　　金：国家科技重大专项(2016ZX05026-002-005)~~

摘　　要：在研究压力对有机质热演化作用的影响过程中,模拟实验主要采用金管热解的方法,所得结果大多没有发现压力对有机质演化存在明显影响。而采用定体积高水压反应釜含水热解实验通常得出压力抑制有机质成熟度的结论。超压盆地的研究结果认为,采用定体积高水压反应釜含水热解实验比较接近实际地质条件,但考虑静岩压力的WYMN-3型温—压生烃模拟仪(兰州油气资源研究中心)或地层孔隙热压生排烃模拟实验仪(无锡石油地质研究所)更具优势。实验与理论相结合的分析认为,高水压通过增大PV来增大反应活化能(E_a),通过减小熵变(ΔS)来减小反应频率因子(A)。现阶段研究超压盆地比较适用的是PreRo^(TM)模型和模型,但两者都只考虑了超压而非孔隙流体压力。因此需要进一步对含流体压力的动力学模型进行研究。另外,目前学界采用的研究方法并不统一,这掣肘了同类实验间的对比,需要一套标准实验体系进行系统性研究。此外,高过成熟度页岩气的勘探与开发为研究压力对高过成熟有机质生气作用的影响提供了宝贵地质资料,但亟需解决海相页岩成熟度的精确测定问题。Most experiments are using gold bags to investigate the effect of pressure on maturation of organic matters,and no significant differences have been found in the majority of the results.However,the results from high-pressure fixed volume autoclave hydrous experiments usually showed pressure retardation on organic matters maturation.Although fixed volume autoclave hydrous pyrolysis may partly simulate the geological conditions under which hydrocarbons are being generated,the WYMN-3 HTHP instrument developed by Lanzhou Institute of Geology,Chinese Academy of Sciences or formation pore space pyrolysis built in Wuxi Research Institute of Petroleum Geology are better to investigate the organic matter maturation in overpressure basins because they also take into account of the lithostatic pressure.And high water pressure enhances the activation energy via increasing the pV work;it also reduces the entropy(ΔS)to decrease the pre-exponential factor(A).At present,using PreRo TM and T-P-R o models would be better for overpressure basins,but both only take account of excess fluid pressure,rather than absolute fluid pressure.So a kinetic model incorporated absolute fluid pressure is needed in further studies.Given that it is hard to compare the results obtained from different experimental methods or instruments,it is quite necessary to establish a set of standard experimental rules to fully understand the pressure effect on organic matter maturation.In addition,the exploration and development of shale gas with high maturity levels provide valuable geological data for studying the effect of pressure on hydrocarbon generation at overmature stages,but this requires the accurate determination of thermal maturity levels of marine shales in which the vitrinite macerals are usually absent or rare.

关 键 词：流体压力 有机质热演化 热模拟实验 动力学模型 

分 类 号：P618.13[天文地球—矿床学]