阜康矿区西部煤层气高产因素追踪

Factors of high?鄄yielding coalbed methane in western Fukang mining area

杜世涛 吴斌 马群 王胜军 刘爽 常仁峰3

新疆维吾尔自治区煤田地质局一六一煤田地质勘探队，新疆 乌鲁木齐 830046 新疆大学地质与矿业工程学院，新疆 乌鲁木齐 830041 中国石油塔里木油田分公司库车油气开发部，新疆 库尔勒 841000

No.161 Coal Exploration Team, Xinjiang Coal Geological Exploration Bureau, Urumqi 830046, China School of Geology and Mining Engineering, Xinjiang University, Urumqi 830041, China Kuqa Oil and Gas Development Department, Tarim Oilfield Company, Korla 841000, China

把阜康矿区西部煤层气高产区的构造位置、水文及水化学变化、煤层顶底板岩性等与甲烷含量相联系，发现构造和岩性控藏并存；通过8口参数井煤层埋深、厚度和煤层物性与含气量的关系发现：1）相同构造位置内煤层含气量随埋深增加而增加，而总体上深部含气量低于浅部。此外，理论含气量高于实测含气量，推断是下部气体向上逸散和次生生物气补偿的结果。2）含气量与煤层厚度呈对数关系，R2为0.650，说明了含气量一定程度上受煤层厚度的影响。3）煤的固定碳、灰分质量分数和密度与含气量的R2分别为0.912，0.900和0.889，相关性较高。4）以固定碳质量分数、灰分质量分数和密度为自变量的线性拟合所得预测与实测含气量符合度较高，R2为0.971。

Relating the structural location, hydrological and hydrochemical changes, and lithology of coal seam roof and floor with coalbed methane content, it is found that the structure and lithology control coexist in the high production western Fukang area. Analyzing the relationship among the coal seam depth, thickness, coal seam physical properties and coalbed methane contents from eight wells, the following conclusions can be drawn: (1) The coalbed methane content of the coal seam increases with the buried depth in the same structural position, while the overall deep coalbed methane content is lower than the shallow part. In addition, the theoretical coalbed methane content is higher than the measured coalbed methane content, which is inferred to be the result of the lower gas uptake and secondary biogas compensation. (2) The coalbed methane content is logarithmically related to the thickness of the coal seam. The R2 of 0.650 indicates that the coalbed methane content is affected by the thickness of the coal seam to some extent. (3) The correlation between fixed carbon, ash and density of coal and R2 of coalbed methane content is high, with 0.912, 0.900 and 0.889 respectively. (4) The coalbed methane content predicted with the linear fit of the fixed carbon, ash and density as independent variables is in good agreement with the measured coalbed methane content, and the R2 is 0. 971.

10.6056/dkyqt201902010