摘要
塔河油田及邻区主要油气储层的地层水以高矿化度为特征 ,长期以来多数人认为这类地层水代表了互不沟通的深层封存环境的产物。该文通过对该区地层水的系统采样分析 ,从地层水的组成特点及所反映的成因环境 ,提出 :a)塔河油田及邻区地层水具有反向化学剖面的特点 ,高矿化度与溶滤地层中的岩盐有关 ;b)氢 (δD)氧 (δ1 8O)同位素明显偏轻 ,δD最大为 -4 2 .0‰ ,最小值为-6 6 .0‰ ,δ1 8O最大值为 2 .7‰ ,最小值为 -6 .0‰ ,反映出地表水渗混溶滤成因的地层水 ;c)通过对比研究区内地层水的主要受地表水渗流 ,溶解地层中的NaCl,而形成高矿化度地层水。塔河油田及邻区是一个水文地质环境相对活跃的地区 ,因此 ,对该地层水的成因环境对该区油气的运聚、保存条件的影响需进一步的考虑。
The formation water contains much higher concentration of solids and total solid concentration ranges from 100g/L to more than 300g/L in the Ordovician, Carboniferous and Triassic reservoirs at Tahe oilfield and adjacents, which was considered as forming in a closed hydrogeological environment and disconnected with each other. The new concludes are made by the analysis of the formation water: a) the chemical profiles of formation water are inversion in the Ordovician, Carboniferous and Triassic reservoirs, the higher total solids concentration is formed by solution of salts in the sediment rocks of the area; b) the δD and δ 18 O are lighter and maybe composed of surface water and formation water; c) the formation of oilfield water is the result of surface water leaching the NaCl containing in the sediments of the area. All these indicate that the hydrogeological environment is not colsed, but opening in the area. The influence of the opening environment in the migration and accumulation of oil and gas must be taken into consideration in the exploration of Tahe oilfield and adjacents.
出处
《石油实验地质》
CAS
CSCD
2002年第1期57-60,共4页
Petroleum Geology & Experiment
基金
中国新星石油公司科研项目 (KT99-T10 3)