矿震是由矿山开采引起的非天然地震活动，鄂尔多斯矿区侏罗纪煤层上方常见白垩系巨厚层状砂岩组，巨厚砂岩组破断、滑移容易诱发巨厚覆岩型矿震，研究揭示高位巨厚覆岩的内部活动演化规律与动力响应特征是巨厚覆岩型矿震灾害防控的基础。笔者基于符拉索夫厚板理论，结合地面探测孔、地表沉降以及微震监测技术，研究了鄂尔多斯某矿综放开采巨厚覆岩结构演化规律及覆岩内部活动特征，揭示了高位覆岩运动诱发矿震机制。结果表明，综放实体煤回采阶段，采空区面积较小，低位顶板垮落较为迅速，顶板破断角64°～72°，高位巨厚覆岩结构无明显裂隙产生，地表下沉量较小；邻空回采阶段，顶板破断高度向巨厚覆岩层扩展，巨厚覆岩层产生裂隙，巨厚覆岩下顶板破裂角有所增加，并且地表沉降量快速增加呈台阶式下沉。白垩系巨厚砂岩层厚较大、强度较高，推导得出邻空回采阶段工作面推进约324.3 m时，巨厚覆岩结构具备发生初次破断的条件，开始出现强矿震事件；并且其周期破断步距为83.7 m。巨厚覆岩结构破断触发矿震机制为：随采空区面积增加，顶板破裂高度逐渐扩展至高位巨厚砂岩层，该巨厚砂岩层发生竖“O-X”型初次破断、滑移以及周期性破断易诱发强矿震事件。研究结论对高位巨厚覆岩型矿震灾害的预防与治理具有指导作用。

Mine earthquake are unnatural seismic activities during mining. In the Ordos mining area in North China, the Jurassic coal seamis commonly overlain by the extremely thick cretaceous sandstone strata. It is easy to trigger strong mine earthquakes when the fractureand slip of the extremely thick strata occur caused by the coal extraction. The movement characteristics and the dynamic response of theextremely thick strata are the basis for mine earthquake prevention and control. Based on Vlasov’s theory, this paper used data from surfaceboreholes, surface subsidence and seismic monitoring to investigate the structure evolution law and movement characteristics of theextremely thick strata in fully-mechanized caving mining of an Ordos coal mine, aiming to reveal the triggering mechanism of the mineearthquakes. The results showed that in the retreating period with no goaf nearby, a small goaf area behind the longwall was presented, and the low roof collapsed rapidly with fracture angles between 64° and 72°, and no obvious fractures were detected in the far-field extremelythick strata, which only caused minor surface subsidence. In the retreating period along with goafs, the roof breaking height expanded tothe extremely thick strata with fracture angles increased, and the fractures emerged in the extremely thick strata, which caused a stepwiseincrease of the surface subsidence. Due to the large thickness and far-field strength of the extremely thick cretaceous sandstone strata, it isdeduced that when the longwall chainage was about 324.3 m, the extremely thick strata met the requirement of initial fracture with a fracturestep of 83.7 m, and the strong mine earthquakes started to be detected. The triggering mechanism of mine earthquake induced bybreakage of extremely thick strata is that: with the increase of goaf area, the fracture height of the low roof gradually extends to the farfieldextremely thick strata, and it is easy to trigger mine earthquake during the vertical “O-X” type initial fracture, fracture adjustment andperiodic fracture of the extremely thick strata. The outcome of this study can provide reference on the prevention and control of mineearthquakes occurred in the far-field extremely thick strata.