以地表观测与最新的地震和钻探等工程资料为依托,运用构造解析研究思路与方法,对韩城矿区南部进行构造应力场与期次恢复,讨论研究区构造变形特征、形成机制及变形期次.分析研究区构造变形特征与构造空间组合关系,划分控煤构造样式,揭示构造成因,进行含煤有利区构造预测与评价.结果显示,区内存在NEE向挤压断块、NEE向复式地堑构造及NNE向挤压隆升—伸展断陷复合构造等3种构造样式,以NEE向复式地堑构造为主;研究区自三叠纪后经历了印支运动期NNW向挤压、燕山运动中期NWW向挤压和喜马拉雅运动期NE向挤压兼右旋剪切与NW—SE向伸展断陷作用3期构造作用,最大主压应力方位分别为335°、285°、44°;NEE向的正断层系是喜马拉雅运动期沿先存的同向优势构造剪节理面进一步发育而成,构成了区内特征性构造,控制了区内煤层空间赋存状况,其发育程度直接影响区内煤炭资源下一步勘查与开发进程.研究区东北部煤层埋藏深度适中,构造简单,是煤炭资源赋存条件最有利区,通过进一步勘查评价,有望成为韩城矿区重要的资源接续地之一.%Based on the surface observation data, the new seismic exploration and drilling engineering data, using the research ideas and methods of structural analysis, the paper carried out staged restoration of tectonic stress field, discussed the tectonic deformation features, mechanism of tectonic formation and phase of deformation. The tec-tonic deformation characteristics and tectonic space combination relationship of the study area were analyzed, tec-tonic styles controlling coalbeds were divided, the tectonic origin was revealed, prediction and evaluation of the favorable coal-bearing areas were conducted. Research results show that there are 3 tectonic styles: NEE squeezed block, NEE multiple graben and horst tectonics and NNE squeezed-stretched composite structure. NEE multiple graben and horst tectonics are major. Since the end of Trias, the study area has experienced NNW squeezed tectonic action during Indosinian movement period, NWW squeezed tectonic action during middle Yanshan movement pe-riod, NE squeezed-right rotated and NW-SE stretching action during Himalaya movement period. The maximum principal compressive stress position are 335°, 285°, 44° in turn. The normal faults in NEE direction are further developed along the early shear joint plane formed in the Himalaya movement period. The faults in NEE direction are the most important tectonic controlling the spatial distribution of coal seams. The degree of faults development controls the next step prospecting and mining process of coal resources. The northeastern part of the study area has moderate buried depth of coal seams, simple tectonics, is the most favorable area, through further exploration and evaluation, may become an important following resource block.
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