石油实验地质
石油實驗地質
석유실험지질
EXPERIMENTAL PETROLEUM GEOLOGY
2014年
3期
352-358
,共7页
泥质烃源岩%蒙脱石伊利石化%层间有机质%页岩气赋存
泥質烴源巖%矇脫石伊利石化%層間有機質%頁巖氣賦存
니질경원암%몽탈석이리석화%층간유궤질%혈암기부존
argillaceous source rock%smectite illitization%interlayer organic matter%shale gas occurrence
页岩气的赋存受多种因素的制约，作为泥质烃源岩中最主要的2种黏土矿物，蒙脱石和伊利石在比表面和微孔隙上存在的明显差异决定了蒙脱石更有利于页岩气的赋存。成岩过程中的压实作用和蒙脱石向伊利石的转化以及由此产生的异常压力都会改变蒙脱石和伊利石的性质，进而影响到对页岩气的吸附。然而，泥质烃源岩中蒙脱石层间有机质的存在，一定程度上延缓了蒙伊化进程，也会对页岩气的吸附产生重要影响。将泥质烃源岩中蒙脱石伊利石化与蒙脱石层间有机质演化以及层间水脱水过程联系起来分析发现，成岩过程中层间有机质排出以前以及层间水排出时期，即从无序伊蒙混层向部分有序混层转化的阶段（伊蒙混层比50％～35％）以及有序伊蒙混层形成的末期（伊蒙混层比15％左右），对应页岩气的有利富集期。
頁巖氣的賦存受多種因素的製約，作為泥質烴源巖中最主要的2種黏土礦物，矇脫石和伊利石在比錶麵和微孔隙上存在的明顯差異決定瞭矇脫石更有利于頁巖氣的賦存。成巖過程中的壓實作用和矇脫石嚮伊利石的轉化以及由此產生的異常壓力都會改變矇脫石和伊利石的性質，進而影響到對頁巖氣的吸附。然而，泥質烴源巖中矇脫石層間有機質的存在，一定程度上延緩瞭矇伊化進程，也會對頁巖氣的吸附產生重要影響。將泥質烴源巖中矇脫石伊利石化與矇脫石層間有機質縯化以及層間水脫水過程聯繫起來分析髮現，成巖過程中層間有機質排齣以前以及層間水排齣時期，即從無序伊矇混層嚮部分有序混層轉化的階段（伊矇混層比50％～35％）以及有序伊矇混層形成的末期（伊矇混層比15％左右），對應頁巖氣的有利富集期。
혈암기적부존수다충인소적제약，작위니질경원암중최주요적2충점토광물，몽탈석화이리석재비표면화미공극상존재적명현차이결정료몽탈석경유리우혈암기적부존。성암과정중적압실작용화몽탈석향이리석적전화이급유차산생적이상압력도회개변몽탈석화이리석적성질，진이영향도대혈암기적흡부。연이，니질경원암중몽탈석층간유궤질적존재，일정정도상연완료몽이화진정，야회대혈암기적흡부산생중요영향。장니질경원암중몽탈석이리석화여몽탈석층간유궤질연화이급층간수탈수과정련계기래분석발현，성암과정중층간유궤질배출이전이급층간수배출시기，즉종무서이몽혼층향부분유서혼층전화적계단（이몽혼층비50％～35％）이급유서이몽혼층형성적말기（이몽혼층비15％좌우），대응혈암기적유리부집기。
Smectite and illite are different with each other from the aspects of specific surface area and microporo-sity. Compared to illite, smectite is more conducive to the occurrence of shale gas. During mudstone diagenesis, compaction and smectite illitization as well as the consequent abnormal pressure could transform the characters of the two minerals, bringing significant influence on the adsorption of shale gas. However, the organic matter in the montmorillonite of the argillaceous source rocks retards the smectite illitization process, making another important impact on shale gas adsorption. Integrating smectite illitization, interlayer organic matter evolution and dehydration process of interlayer water, the study shows that the favorable rich region for shale gas is correlated with the period prior to the stage when interlayer organic matter and water have been discharged, namely from the convertion stage of chaotic mix-layer illite/smectite to the partially ordered mixed-layer illite/smectite ( smectite for 50%-35% in I/S) and the final phase of ordered mixed-layer illite/smectite( smectite for about 15% in I/S) .
