准东地区煤炭气化地质评价与有利区预测

首先从地质构造、煤层厚度、煤层埋深、煤岩煤质、煤层顶板岩性及水文地质条件出发,对准噶尔盆地东部含煤地层地质条件进行分析,探究了准噶尔盆地东部煤层地下气化地质条件的可行性,研究区发育多套厚煤层,煤阶较低,煤层层数多,灰分挥发分较高,倾角较大,埋深适中,顶底板岩性为泥岩、粉砂岩和砂岩,断层封堵较好,发育较好的隔水层,综合分析认为本区适宜进行煤炭地下气化工作;其次,从资源条件、储层条件与开发条件出发,优选出9个符合本区地质特征的有利区三级评价参数,建立多层次数学评价模型,将全区煤炭地下气化潜力划分为三类,优选出沙帐断褶带、梧桐窝子凹陷、阜康断裂带三个区块作为煤炭地下气化的最佳区域,对准东地区后续的地下气化实施提供地质依据。

Geological Evaluation for Underground Coal Gasification and Favorable Area Optimization in Eastern Junggar Basin

The geological conditions of coal-bearing strata in eastern Junggar Basin are analyzed based on geological structure, coal seam thickness, coal seam burial depth, coal rock and coal quality, coal seam roof lithology and hydrogeological conditions. The feasibility of underground coal gasification geological conditions in eastern Junggar Basin is discussed. Several sets of thick coal seams are developed in the study area, with lower coal rank, more coal seams, higher volatile ash, bigger dip angle, moderate burial depth, mudstone, siltstone and sandstone in roof and floor lithology, better fault sealing and well developed water barrier. Comprehensive analysis shows that underground coal gasification is suitable in this area. Secondly, based on resource, reservoir and development conditions, nine three-level evaluation indices are selected to establishe multi-level mathematical evaluation model. The potential of underground coal gasification is divided into three categories in the whole region. the three blocks of Shazhang Fault-fold Belts Zone, Wutongwozi Depression and Fukang Fault Zone are the best areas for underground coal gasification. which can provide geological basis for underground coal-bed methane gasification in eastern Junggar Basin.