塔克拉玛干沙漠中部地区两类半隐蔽格状沙障内部沉积粒度特征浅析

Study on Grain Size Characters in Different Material Semi-buried Checkerboard in the Center Area of Taklimakan Desert

选取塔克拉玛干沙漠石油公路K286处尼龙网方格和塔中作业区气井附近水泥方格两种不同材料的半隐蔽格状沙障沙样进行粒度组成分析,分析内容包括平均粒径、标准偏差、偏度、峰度、平均粒径与标准偏差散点图和代表性样品累积概率曲线图。结果表明,尼龙网方格中心沉积颗粒未必最细,水泥方格中心部位沉积颗粒最细,其原因与方格内的流场有关。散点图显示,水泥方格中心处沉积粒度区间与方格其他位置差别最大。累积概率曲线表明,跃移组分与蠕移组分之间的截点差别最大,即动力作用复杂,同时说明风力对粗沙粒沉积过程作用不明显;悬移组分与跃移组分之间截点在不同位置差别最小,表明在一定粒径范围内的粒径大小对动力作用的响应是非常明显的。

Sand samples, collected from both nylon semi-buried checkerboard and cement semi-buried checkerboard in the center of Taklimakan Desert, are analyzed with grain-size characteristic parameters, mean grain-size to standard deviation scatter diagram and accumulative probability diagram. The results show that, first, the fine grain-size sands locate in the center of cement semi-buried checkerboard other than in the center of nylon semi-buried checkerboard, largely because of differential air flow in checkerboard; the accumulative probability diagram indicates that the wind forces in cement semi-buried checkerboard are more complex than that in the nylon checkerboard. And big grain-size sands play an important role in the grainsize characteristic parameters. Last, it is obviously that fine grain-size sands are affected by wind force.