为了丰富离层发育规律的研究方法，以石拉乌素矿221_上08工作面为对象，通过分布式光纤（BOTDR）及定点光纤对离层位置进行综合确定，结合颗粒流PFC^2D数值模拟，对大采高、大采深条件下采动覆岩离层发育规律进行研究。结果表明：随着工作面推进，离层空间在关键层底部自下而上向主关键层底部发育，离层发育埋深在440、396、376、331、321、296 m附近，层位止于粗砂岩主关键层底部；覆岩运移主要经历下位关键层沉降、上位亚关键层快速沉降、向粗砂岩主关键层底部发展、主关键层运移阶段；离层层位与工作面推进距离呈正比，且离层发育主要分为孕育（Ⅰ）-加速扩容（Ⅱ）-压密阶段（Ⅲ）3个阶段。

To enrich the research methods for studying the development law of bed separation, this paper takes the upper 08 working face of 221 in Shilawusu Mine as the research object, and comprehensively determines the location of bed separation through distributed optical fiber (BOTDR) and fixed-point optical fiber. The particle flow code (PFC^2D) is used to study the pattern of the separation layer development under the conditions of large mining height and large mining depth. The results show that, as the working face advances away from the cutting hole, the separated layer develops intermittently from the bottom to the bottom of the key layer, and the depth of separation layer development is around 440 m, 396 m, 376 m, 331 m, 321 m and 296 m, and the layer stops at the bottom of the main key layer of coarse sandstone. The overburden transport mainly goes through the stages of subsidence of the lower key layer, rapid subsidence of the upper sub-key layer, development of overburden movement towards the bottom of the main key layer of coarse sandstone, and transport of the main key layer. The separated layer position is proportional to the advancement distance of the working face, and the development of the separated layer is mainly divided into three stages, which are gestation (Ⅰ)-accelerated expansion (Ⅱ)- compression stage (Ⅲ).