川西拗陷上三叠统气田水化学形成演化的重溯  

Restoration of the Formation and Evolution of Upper Triassic Gas Field Water in Chuanxi Depression

作　　者：汪珊[1] 张宏达[1] 孙继朝[1] 荆继红[1] 

机构地区：[1]中国地质科学院水文地质环境地质研究所,河北石家庄050061

出　　处：《地球学报》2009年第5期665-672,共8页Acta Geoscientica Sinica

基　　金：国家自然科学基金项目(编号:40572143)资助

摘　　要：本文在研究区沉积演化、构造演化和上三叠统含水系统、水文地质期定位的基础上,论证了T3x2水起源于35g/kg的海相同生沉积盐水,经历了沉积、沉压埋藏、构造热液3个"期"的浓缩盐化正向变质,演化成为最高浓度160g/kg的海相后生沉积孔隙裂隙卤水、浓卤水;T3x4、T3x6水均起源于陆相同生沉积淡水,T3x4经历了沉积、沉压埋藏—淋滤、沉压埋藏、构造热液4个"期",主要是高度浓缩盐化正向深变质,演化成为最高浓度100g/kg的后生沉积孔隙裂隙盐卤水;T3x6与T3x2经历的期相同,经高度浓缩盐化正向深变质,演化成为最高浓度84g/kg的后生沉积孔隙裂隙盐卤水。Based on studies of deposition, tectonic evolution, Upper Triassic aquifer system and hydrogeological age, this paper holds that T3x^2 groundwater came from marine syndepositional brine of 35 g/kg, and experienced three ＂periods＂ of inspissation salt positive metamorphism, namely sedimentation, compaction and tectonic hydrothermal activity. Afterwards, they turned into deuterogenous sedimentary salt brine and strong salt brine of 1160 g/kg. Both T3x^4 and T3x^6 groundwater came from terrestrial facies syndepositional freshwater. T3x^4 experienced four ＂periods＂, i.e., sedimentation, compaction-leaching, compaction and tectonic hyrothermal activity. The major part was characterized by strongly concentrated salification and forward metamorphic process, and the later evolution into deuterogenous sedimentary pore and fissure salt brine of 100 g/kg. T3x^6 and T3x^2 experienced the same periods, resulting in strongly concentrated salification and forward metamorphic process and forming deute-rogenous sedimentary pore and fissure salt brine groundwater of 84 g/kg.

关 键 词：水化学 形成演化 上三叠统 川西拗陷 

分 类 号：P641.462[天文地球—地质矿产勘探]