布尔台矿井构造特征与形成机制

The features and formation mechanism of structures in Burte mine

针对布尔台矿井发育的中小型构造严重制约煤矿综采问题,通过详细的井下地质观测和地表地质调查,从构造几何学和构造成因研究入手,讨论了矿井构造成因类型、古构造应力场以及构造形成机制。研究表明:布尔台矿井次级褶皱是延安组在晚侏罗世受NNE-SSW向挤压应力作用,浅部构造层次发生纵弯褶皱变形的产物,且变形强度弱-中等。破裂型层滑断层、揉皱型层滑断层、复合型层滑断层、高角度正断层及其伴生的牵引褶皱,是延安组在早白垩世晚期NE-SW向近水平拉伸应力作用下发生大规模的伸展滑脱运动形成的。两期构造叠加形成了现今的构造格架。

Aiming at the problems of minor-meso scale structures developed in Burte mining shaft, which restrict integrated mechanized mining seriously, through detailed underground geological observation and surface geological surveys, the genetic types of structures, palaeotectonic stress field and structural formation mechanism are discussed from the view of structure geometry and tectonic origin. Research results show that the subsidiary folds in the Burte mine were settled under NNE-SSW compression stress in Yanan Formation during late Jurassic, which occurred in shallow structural layer. The deformation intensity was weak to middle. Broken interlayer gliding faults, rumpled interlayer gliding faults, composite interlayer gliding fault, high angle downthrown faults, and associated drag-folds were established by about NE-SW stretching stress, which caused a large scale of extensional sliding movement in Yan＇an Formation in the late period of early Cretaceous. The basic structural framework in the mining shaft was formed by two stages of superimposed deformation.