摘要
The Kumtag Desert is located in the arid northwestern portion of China,and is considered China’s sixth-largest desert.Grain-size analysis of the sand plays a very important role in differentiating sedimentary environments,determining the ways that sediments are transported,estimating hydrodynamic conditions,and analyzing grain-size trends.The analysis of the grain size of 20 sand samples that were taken from mid-northern,north margin,western,middle,southern,and southeast margins of the Kumtag Desert shows that grain sizes are vastly different.The grain-size parameters fall in the following range:the median diameter Mz = 1.55Φ-2.92Φ,the standard deviation σI= 0.41-1.11,the skewness SKI = ?0.11-0.31,kurtosis KG = 0.77-1.23.The frequency curves of grain size have characteristics with single peaks and multi-peaks,and most of the sand samples’ skewness appears close to asymmetric.The analytical results reveal that the sediments of the Kumtag Desert are complex and diverse,which affected by such forces as wind deposition,lacustrine sediment,and alluvial and proluvial river deposits.
The Kumtag Desert is located in the arid northwestern portion of China,and is considered China's sixth-largest desert.Grain-size analysis of the sand plays a very important role in differentiating sedimentary environments,determining the ways that sediments are transported,estimating hydrodynamic conditions,and analyzing grain-size trends.The analysis of the grain size of 20 sand samples that were taken from mid-northern,north margin,western,middle,southern,and southeast margins of the Kumtag Desert shows that grain sizes are vastly different.The grain-size parameters fall in the following range:the median diameter Mz = 1.55Φ-2.92Φ,the standard deviation σI= 0.41-1.11,the skewness SKI = ?0.11-0.31,kurtosis KG = 0.77-1.23.The frequency curves of grain size have characteristics with single peaks and multi-peaks,and most of the sand samples' skewness appears close to asymmetric.The analytical results reveal that the sediments of the Kumtag Desert are complex and diverse,which affected by such forces as wind deposition,lacustrine sediment,and alluvial and proluvial river deposits.
基金
supported and assisted by the National Science and Technology Infrastructure Program (2006FY110800)
the National Natural Science Foundation Project (40775019)
the National Scientific Support Planning Subject (2008BAC40B05-01)
the XinJiang Uighur Autonomous Region Science and Technology Key Projects (200833119)