贵州省黔西县官寨井田地质构造特征及力学分析

黔西官寨井田主体构造为一背斜，位于关寨向斜与黔西向斜之间的隆起部位，走向NE-EW，井田受三条大断层（F1、F2、F3）切割，自然划分为三个区块：北区块（F2以北）为向N倾的单斜，地层倾角缓，断层稀少，构造简单；西南块区（F2以南、F12以西）断层发育，为构造复杂地段；南东区块（F2以南、F12以东）构造中等。通过对井田构造特征及应力场分析，认为官寨井田构造主要形成于燕山期，早期产生反时针NW-SE向的挤压，形成关寨向斜和F12等断层，从中期到晚期转为顺时针扭动，产生NE-SW向挤压，形变加剧，形成沙井背斜和F1断层，喜山期使井田内NE、NW向构造进一步演化，导致沙井背斜轴和F2断层产生弧形弯曲。根据井田构造发育特征，建议矿井开采首选地段应为沙井背斜的北翼，南翼西部构造复杂，需进一步研究断层分布规律，以正确指导煤矿的安全生产。

Geological Structural Features and Mechanical Analysis in Guanzhai Minefield, Qianxi County, Guizhou Province

The main structure of Guanzhai minefield is an anticline, situated at uplifting part between the Guanzhai syncline and Qianxi syncline, strike NE-EW, the minefield is dissected by three major faults （F1, F2 and F3） and divided into 3 sectors： The north sector （to the north of F2）, is N dipped monocline, strata are gently dipped with very few faults, thus structure is simple; the southwestern sector （to the south of F2, west of F12） faults developed, structure is complex; the southeastern sector （to the south of F2, east of F12）, structure is moderate. Through minefield structural features and stress field analyses, figured out that the minefield structure is mainly formed during Yanshanian stage, counter clockwise NW-SE compression produced in the early stage, the Guanzhai syncline and faults including F12 were formed, from middle stage to late stage changed into clockwise torsion, NE-SW compression produced, deformation intensified, thus Shajing anticline and F1 fault formed, the Himalayan orogeny made the evolution of NE, NW direction structures in the minefield further, brought on arcuated bending of Shajing anticline axis and F2 fault. According to structural development characteristics, it is proposed that preferred first stage coal mining sector should be in north limb of Shajing anticline, while western south limb has complex structures, regular distribution fault pattern need to be further studied for the sake of to guide coalmine safety in production correctly.