The magnetic fabric characteristics and environment signification of modern fluvial deposit in the Middle Reaches of Yangtze River

摘要

In order to establish magnetic fabric identification on different sedimentary environment in the middle reaches of Yangtze River,we studied the magnetic fabric parameter character of modem river's deposits of the different water level and sedimentary environment.The result reveals that,① In the straight river course,the statistical average value of magnetic fabric parameter κ,P,F,Fs,T and E are larger than those in winding river course.However,the value of q and L are less than those in Winding river.② The direction of declination of long axis of anisotropy magnitude ellipse in straight river course is very clear.And it has a good consistency with the direction of flow.However,the direction of declination of long axis of anisotropy magnitude ellipse in winding river course is scattered.③ From high-flood land,low-flood land to sand-bar in the center of river,the statistic average value P,F,T,FS,E of magnetic fabric parameters of deposit change from small to large slowly.But q and L have the trend from large to small.The study result is significant for the study of evolution,vicissitudes and identification of ancient river sources.