在偃龙煤田西部发现龙门滑动构造已有60多年,尚未整体上对其形成机制及控煤作用深入研究.采用断块掀斜理论和构造应力场理论,通过对物质条件、动力条件、边界条件、诱发条件等运动条件分析,说明龙门滑动构造是在嵩山隆起基础上,受东西向、北西2组边界断裂组成断块掀斜控制,在华北古板块地壳活动频繁的背景下,诱发重力失稳的煤系岩层由掀起端向倾斜端滑移,经过燕山期晚期至喜马拉雅期早期的长期间断滑动形成的.滑动构造会造成二1煤层上覆岩层缺失,引起煤厚强烈变化和煤层顶板变形,导致水文地质条件复杂化.弄清龙门滑动构造的形成机制,对分析偃龙煤田西部煤层赋存条件、煤厚变化规律等控煤特征及矿床开发管理有重要意义.%It has been more than 60 years for Longmen Sliding Structure in the western region of Yanlong Coal Field to be discovered. However,there is no further study on the formation mechanism and the coal control action as a whole.The fault block tilted movement theory and the tectonic stress field theory,and the analysis on the material condition,the dynamical condition,the boundary condition, the induced condition and other conditions,to explain:on the basis of Songshan′s upheaval,the coal measures strata is controlled by the tilted fault block,which consists of two boundary fractures of the east-west direction and the north-west direction.Under the frequent crustal motion of North China ancient plate,the coal measures strata has no gravity instability and slides from the lifting end to the tilting end.The long continuous sliding of the coal measures strata from the late of Yanshan period to the early of Himalaya period forms Long-men Sliding Structure.The sliding structure results in the lack of the overlying strata of the two-one coal seam,the intense change of the coal thickness and the deformation of the coal roof,and the complication of the hydro-geological condition.Understanding the formation mechanism of Longmen Sliding Structure is meaningful to the analysis on the coal seam occurrence conditions in the western region of Yanlong Coal Field,the coal controlling characters like the thickness change law,and the development and management of the mineral deposit.
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