台湾南部泥火山与伴生气地质地球化学特征及其油气地质意义  

Geology of Mud Volcanoes and Geochemistry of Associated Gas in Southern Taiwan and Its Significance to Petroleum Geology

作　　者：何家雄[1] 崔洁[2] 翁荣南 祝有海[4] 黄霞[4] 谢奇勋 龚晓峰[1] 

机构地区：[1]中国科学院边缘海地质重点实验室,广东广州510640 [2]广东省技术经济研究发展中心,广东广州510070 [3]台湾中国石油股份有限公司探采事业部,台湾台北11010 [4]中国地质科学院矿产资源研究所,北京100037

出　　处：《天然气地球科学》2012年第2期319-326,共8页Natural Gas Geoscience

基　　金：国家自然科学基金(编号:41040043);国家重点基础研究发展计划项目(编号:2009CB219501)联合资助

摘　　要：台湾省南部泥火山异常发育,泥火山伴生气地质地球化学特征具有明显的沉积型壳源成因特点,并非火山幔源活动成因。这些泥火山活动所伴生的天然气组成大多数均以甲烷为主,乙烷及其重烃含量甚低。泥火山伴生气甲烷碳同位素值为-31.7‰～-35.9‰,二氧化碳碳同位素值为-10.0‰～-15.2‰。稀有气体氦、氩同位素值偏低。其中,3 He/4 He(Ra)即R/Ra值分布在0.21～1.34之间,40 Ar/36 Ar值则在304.6～330.0之间。上述地球化学特征表明,这些泥火山伴生气主要属热解有机成因的成熟烃类气,且主要是较年轻的新近纪巨厚海相沉积烃源岩的贡献。深入分析泥火山地质特征及伴生气地球化学特点,能为建立这种特殊的天然气成因成藏机制提供重要地质依据与基础研究资料,因此,具有十分重要的油气地质意义。A plenty of mud volcanos exist in the southern Taiwan,and the geochemistry of mud volcano-associated gas is representative of crustal gas origin rather than volcanic mantle one.The chemical compositions of associated gas are dominated by methane,the content of ethane and propane is very low.Carbon isotope values of methane and carbon dioxide are ranged from-31.7‰ to-35.9‰ and-10.0‰ to-15.2‰,respectively.Helium and Argon isotopes are low,with R/Ra ratios of 0.21-1.34,and 40Ar/36Ar ratios of 304.6-330.0.Geochemistical parameters of associated gas suggest that the mud volcano-associated gas as thermally decomposed hydrocarbon gas would be mainly sourced from the Neogene marine source rock with big thickness.It is helpful to understand the particular mechanism of accumulation of associated-gas based on information of geology of mud volcanoes and geochemistry of associated-gas gas.

关 键 词：台湾南部 泥火山地质特征 伴生气地球化学特征 油气地质意义 

分 类 号：TE122.113[石油与天然气工程—油气勘探]