CAJ | 학술논문

鄂尔多斯盆地南部侏罗系具有较好的煤层气勘探潜力，但煤层气成因有待深入研究，弄清楚其成因类型能够有效指导该区下一步勘探开发方向。基于区域地质条件、煤层气样品组分、稳定同位素等分析，对其成因进行了探讨。结果表明，研究区浅部的彬县、焦坪、黄陵地区煤层气δ13 CCH4一般介于－81‰～－57‰，煤层气干燥系数一般大于100，δDCH4一般介于－236‰～－234‰，煤层气为晚期生物成因，同时，地层水矿化度低，煤岩孔隙度较高，渗透性较好，具备生物气生成的地质条件；深部合水-宁县地区煤层气δ13 CCH4一般介于－49‰～－35‰，煤层气干燥系数一般小于100，是典型的热成因气，地层水矿化度高，呈酸性，不利于生物气的生成。
악이다사분지남부주라계구유교호적매층기감탐잠력，단매층기성인유대심입연구，롱청초기성인류형능구유효지도해구하일보감탐개발방향。기우구역지질조건、매층기양품조분、은정동위소등분석，대기성인진행료탐토。결과표명，연구구천부적빈현、초평、황릉지구매층기δ13 CCH4일반개우－81‰～－57‰，매층기간조계수일반대우100，δDCH4일반개우－236‰～－234‰，매층기위만기생물성인，동시，지층수광화도저，매암공극도교고，삼투성교호，구비생물기생성적지질조건；심부합수-저현지구매층기δ13 CCH4일반개우－49‰～－35‰，매층기간조계수일반소우100，시전형적열성인기，지층수광화도고，정산성，불리우생물기적생성。
Exploration activities have proved that Jurassic Formation of South Ordos Basin has great potential of CBM (coalbed methane) ,to clarify the genetic type of the CBM can effectively guide the further exploration ,for this purpose ,the geologic characters of the formation ,the gas samples and stable isotope of the CBM were analyzed ,and the results show that theδ13CCH4 value of the shallow layers of Bin County ,Jiao-ping and Huangling area range between -81‰ ~ -57‰ ,the dry factors are mainly above 100 ,δDCH4 mostly distribute between-236‰ ~ -234‰ ,all the features above proved that the CBM is biogenesis gas ,and the reservoir of these area is characterized by low water salinity and relatively good penetration condition ,which is favorable for biogenesis gas’s generation .While for the deeper zone of He Shui-Ning County area ,theδ13 CCH4 value ranged from - 49‰ ~ - 35‰ ,the CBM dry factors are less than 100 ,which is typically thermogenic gas ,and also ,its formation water is not conducive to the generation of biogenic gas because of the high salinity and acidic property .