Testing research of coal layer safe extraction in efflorescent oxygenized belts 风氧化带内煤层安全开采的试验研究
2.
The following new opinions : without caving zone coal layer extraction in efflorescent oxygenized belts ; two effects of blocking water and preventing water flowing fractured zone from going on developing after mining effect ; appropriately enlarging the extraction thickness were presented 提出了风氧化带煤层开采无垮落带；受采动影响后，具阻水和抑制导水裂隙带继续发展的双重作用以及适当加大开采厚度等新观点。
3.
Based on testing data in worksite and engineering practice , the strata damage movement characteristics , rock properties of weathered zone and qualitative and quantitative analysis of the mechanism of coal layer safety extraction in efflorescent oxygenized belts were discussed 摘要根据现场观测和工程实践，论述了风氧化带内煤层开采时，覆岩破坏移动特征，风化带岩石属性和风氧化带内煤层安全开采机理的定性、定量分析。
4.
Therdly because of the influence of terrain and geological structure , arenaceous resources of different regions are different in mu us . sands are mainly from riverway in northwest ; from efflorescent cretaceous sandstone on account of higher topography in the middle part of mu us ; and sands resources are intricated in southeast , mainly including riverway sands , sands blown by the wind and embedded sands under so 3 、毛乌素沙地因受地形和地质构造影响，不同区域的砂质来源情况不尽相同，西北部地区主要为河道沙；中部地区地势较高，为白垩系基岩裸露而风化成沙；东南部地区沙质来源情况复杂，主要有：现代河道砂、风积沙、也有埋藏在现代壤土之下的出露古沙。
