论文部分内容阅读
以贵州松河区块煤层气井产出水跟踪测试数据为依据,系统研究了该区产出水化学特征及其地质意义.认为煤层气井产出水地球化学性质与产能之间关系密切,可用产能响应指数来反映煤层气井的产能水平.研究结果表明:煤层气井产出水Na~+和HCO_3~-含量高,Ca~(2+),Mg~(2+)和SO_4~(2-)含量低,是煤层气藏富集的表现.特征离子K~+和Cl~-异常高,随排采时间的增加逐渐减小,暗示产出水受到了压裂液的污染,δD偏重,表现出明显的D漂移特征,则是煤层水的典型特征,总体指示产出水具有煤层水混合压裂液的特征.Na~+,K~+,Cl~-在井网空间分布表现出低部位为高值,分别在3g/L,160mg/L,5g/L以上,高部位为低值,分别在2g/L,100mg/L,3g/L左右,是高部位水往低部位运移的结果,而HCO_3~-表现出高部位值大,在900mg/L左右,低部位值小,在600mg/L左右,推测为低部位CO_2向高部位运移的结果,存在“气水分异”现象.
Based on the data of tracking test of output water of coalbed methane wells in Songhe block of Guizhou Province, the chemical characteristics of output water in this area and its geological significance are systematically studied. It is considered that there is a close relationship between the geochemical properties and productivity of coalbed methane well, Response index to reflect the production capacity of coalbed methane wells.The results show that the content of Na ~ + and HCO_3 ~ -, Ca ~ (2 +), Mg ~ (2+) and SO_4 ~ (2-) Low, which is the manifestation of CBM enrichment.The characteristic ions K ~ + and Cl ~ - are abnormally high and decrease gradually with the increase of extraction time, which implies that the produced water is polluted by fracturing fluid and the δD is heavy, The obvious D drift characteristic is the typical characteristic of coal seam water, which indicates that the produced water has the characteristics of mixed water and fracturing fluid in coalbed water.The spatial distribution of Na ~ +, K ~ +, Cl ~ - High values of 3g / L, 160mg / L, 5g / L or more, high value of low, respectively 2g / L, 100mg / L, 3g / L or so, , While HCO_3 ~ - showed a large value of high site, about 900mg / L, low site value is small, about 600mg / L, presumed to result in low site CO_2 migration to high sites, phenomenon.