Discovery of Potassium-Bearing Cuttings from the Well Yangta 4 in the Kuqa Depression and Seam Division

The world petroleum exploration suggests that,about70%of the world’s potash resources were discovered during oil and gas exploration(Zheng et al.,2007).The Kuqa depression in the Tarim basin is abundant with petroleum exploration data,and

煤柱影响下被保护层开采应力演化特征数值模拟研究

为探究煤层群开采过程中,煤柱对被保护层开采应力演化特征的影响规律,以良村煤矿1801工作面为工程实际,应用FLAC3D应变-软化模型对煤柱影响下被保护层工作面开采时支承压力和三维应力的演化规律进行了数值模拟。研究结果表明:被保护层工作面除煤柱影响区之外整体处于卸压状态。支承压力演化规律与被保护层工作面开采进度紧密相关。当工作面推进位置处于煤柱影响区时,支承压力值突增至原岩应力的1.25倍,曲线呈快速上升态势。距离保护层的层位越高,垂直应力值越小,当层位距大于26m时,三维应力分布基本不再受煤柱的影响。煤柱影响下被保护层工作面范围可分为煤柱影响区、煤柱影响扩界区和卸压区,以此提出了瓦斯突出分区防治策略,在该工作面实施了高位穿层钻孔、采空区埋管瓦斯抽放、网状穿层钻孔和大直径卸压钻孔的综合措施,累计抽放瓦斯90余天,抽放瓦斯64805m3,效果检验指标均不超限,实现了安全回采。