榆神矿区首采煤层及上覆岩层工程地质特征

榆神矿区是陕北大型煤炭基地的重要组成部分,区内煤炭资源丰富。近年来,该矿区煤炭开发与生态环境、地质环境的矛盾日益突出。通过分析榆神矿区首采煤层分布、厚度、埋深及其上覆岩层的厚度和顶面形态,根据岩石成因、工程地质特征及物理力学性质,将该区岩(土)体划分为4个类型和7个岩组: 松散岩类(沙层组、土层组)、软岩类(风化岩组、煤岩组、烧变岩组)、较软岩类(粉砂岩与泥岩互层岩组)和较坚硬岩类(砂岩组),总结了各岩组的分布、厚度和物理力学特征。结果表明: 矿区煤层顶板多为中等—难冒落型顶板,局部地段属易冒落型顶板; 粉砂岩及细粒砂岩底板属稳定型底板,泥岩底板稳定性差。为指导矿区规划、环境评估及煤炭开发提供依据,对切实转变陕西煤炭发展方式、促进生态环境友好型矿山的发展具有积极意义。

Engineering geological characteristics of the first mined coal seam and overlying strata in Yushen mining area

Yushen mining area is an important component of the large-scale coal base in North Shaanxi, whose coal resources are abundant. In recent years, the contradiction between coal development and ecological and geological environment has become more and more prominent. Through the analysis of the distribution, thickness and buried depth of the first mined coal seam, thickness of overlying strata and top surface morphology in Yushen mining area, and according to petrogenesis, engineering geological characteristics and physical mechanical property, the authors divided the rock (soil) mass of the mining area into four rock types and seven rock groups, and summarized the distribution, thickness and physical mechanical property of each rock group. These rock types and rock groups include loose rock type (sand layer group, soil group), soft rock type (weathered rock group, coal group, burnt rock group), sub-soft rock type (siltstone-mudstone group) and sub-hard rock type (sandstone group). The research results show that the coal seam roofs in the mining area are mainly difficult falling-in roofs, and there are easy falling-in roofs in partial areas. The floors of siltstone and fine-sandstone belong to the stable floor, and the mudstone floor has poor stability. The research can provide some reference for the mining area planning, environmental assessment and coal development, which will have a positive effect on the transformation of coal development mode and the promotion of eco-environment-friendly mines development in Shaanxi.