Magnetic Fabric Characteristics of Wushan Loess and Its Paleowind Field in the Wushan Area

摘要

In order to discuss the magnetic fabric characteristics of aeolian sediment and paleowind field evolution in the Three Gorges region,we tested newly discovered loess section that was located in Wushan.The results showed that:①Magnetic fabric parameters P,F,L values of Wushan section are smaller;the value of q is larger,indicating that the depositional environment and paleowind field field in accumulation of “Wushan” loess are not very stable.②The maximum spindle declination rose figure of magnetic susceptibility ellipsoid in Wushan section indicates that the main wind direction is NW-SE in the period of the Wushan loess accumulation,but there is other direction of wind interference.③The statistics of the magnetic fabric parameters and maximum spindle in five different deposition stages show that the depositional environment and paleowind field of the different times are in different in the Wushan area;there are the following characteristics in paleowind field of this area: Change form NNE-SSW to NW-SE,then to SW-NE,last to NW-SE.