石油与天然气地质
石油與天然氣地質
석유여천연기지질
OIL & GAS GEOLOGY
2015年
4期
651-658
,共8页
王香增%范柏江%张丽霞%姜呈馥
王香增%範柏江%張麗霞%薑呈馥
왕향증%범백강%장려하%강정복
解吸实验%孔缝特征%页岩气赋存%长7段页岩%鄂尔多斯盆地
解吸實驗%孔縫特徵%頁巖氣賦存%長7段頁巖%鄂爾多斯盆地
해흡실험%공봉특정%혈암기부존%장7단혈암%악이다사분지
desorption experiment%pore and fracture feature%shale gas charging%Chang 7 member%Erdos Basin
页岩的储集空间不但影响页岩气的储量,还影响页岩气井的产能。研究页岩气的赋存空间及赋存过程有助于确定勘探靶位。综合利用野外露头、岩心观察、薄片分析及扫描电镜等多种手段,研究了鄂尔多斯盆地陕北斜坡构造带延长探区延长组长7段页岩的储集空间类型及其特征。在此基础上,通过解吸模拟实验进行页岩气气体特征分析,最终重建页岩气的赋存过程。结果表明,延长探区长7段页岩发育原生粒间孔、次生溶蚀孔、有机质生烃孔、构造张裂缝及层间页理缝等多种孔、缝类型。在解吸过程中,分子直径较小的甲烷气最容易解吸,含13 C的甲烷分子则相对解吸困难。在生气初期,长7段页岩生成的少量重烃气主要吸附于有机质表面及微孔中;在生气期,页岩优先吸附重烃气和具13 C的甲烷气;当满足页岩的吸附和溶解等残留需要后,气体以游离态赋存。
頁巖的儲集空間不但影響頁巖氣的儲量,還影響頁巖氣井的產能。研究頁巖氣的賦存空間及賦存過程有助于確定勘探靶位。綜閤利用野外露頭、巖心觀察、薄片分析及掃描電鏡等多種手段,研究瞭鄂爾多斯盆地陝北斜坡構造帶延長探區延長組長7段頁巖的儲集空間類型及其特徵。在此基礎上,通過解吸模擬實驗進行頁巖氣氣體特徵分析,最終重建頁巖氣的賦存過程。結果錶明,延長探區長7段頁巖髮育原生粒間孔、次生溶蝕孔、有機質生烴孔、構造張裂縫及層間頁理縫等多種孔、縫類型。在解吸過程中,分子直徑較小的甲烷氣最容易解吸,含13 C的甲烷分子則相對解吸睏難。在生氣初期,長7段頁巖生成的少量重烴氣主要吸附于有機質錶麵及微孔中;在生氣期,頁巖優先吸附重烴氣和具13 C的甲烷氣;噹滿足頁巖的吸附和溶解等殘留需要後,氣體以遊離態賦存。
혈암적저집공간불단영향혈암기적저량,환영향혈암기정적산능。연구혈암기적부존공간급부존과정유조우학정감탐파위。종합이용야외로두、암심관찰、박편분석급소묘전경등다충수단,연구료악이다사분지협북사파구조대연장탐구연장조장7단혈암적저집공간류형급기특정。재차기출상,통과해흡모의실험진행혈암기기체특정분석,최종중건혈암기적부존과정。결과표명,연장탐구장7단혈암발육원생립간공、차생용식공、유궤질생경공、구조장렬봉급층간혈리봉등다충공、봉류형。재해흡과정중,분자직경교소적갑완기최용역해흡,함13 C적갑완분자칙상대해흡곤난。재생기초기,장7단혈암생성적소량중경기주요흡부우유궤질표면급미공중;재생기기,혈암우선흡부중경기화구13 C적갑완기;당만족혈암적흡부화용해등잔류수요후,기체이유리태부존。
Reservoir spaces in shale controls not only the shale gas reserves,but also the production capacity of shale gas wells ,thus the study of reservoir space characteristics and charging process of lacustrine shale gas helps greatly to determine exploration targets.This paper integrates various technologies,such as field outcrops,core observation,thin section and SEM Pore Imaging,to study the reservoir space types and their features of Chang 7 shale of the Yanchang Fm in Yanchang Block of Shanbei slope zone,Erdos Basin.Combined with the experimental results of shale gas components,this paper simulates the shale gas charging process.The results show that,the reservoir spaces of Chang 7 shale are dominated by primary intergranular pores,secondary dissolved pores,organic pores,structural fractures and lamellation fractures.In the desorption process,the methane gas with relatively small molecule size is the first to be released from shale.However,the methane gas containing 13 C is relatively more difficult to be released from the shale.In the early gas generating stage,the small portion of heavy gas gener-ated from Chang 7 shale mainly adsorbed on the organic surface and micropores.In the main gas generating stage,heavy gas and 13 CCH4-containing methane had priority over other gas components to be absorbed in the shale reservoir.Only when the adsorption capacity and dissolution capacity of shale were met,could the free gas exist in the shale reservoir.