GRAIN-SIZE CHARACTERISTICS AND SEDIMENTARY ENVIRONMENT IN THE LACUSTRIAN DEPOSIT OF CHAOHU LAKE,THE YANGTZE DELTA REGION
DU Lei,YI Chao-lu,PAN Shao-ming(Department of Urban and Resources,Nanjing University,Nanjing 210093,China)
Three lacustrian sediment samples were collected from Chaohu Lake in December 2002 in the Yangtze delta region. These samples were analyzed using a Laser Analyzer and obtained grain-size parameters. Sedimentation rates were determined with radioisotopes ~(137)Cs and the average sedimentary rates are 0.29cm/a,0.35cm/a and 0.24cm/a in Cores C1, C2 and C3, respectively. The grain-size parameters of the deposits vary regularly with the fluctuation of hydrodynamics. There are many differences of sedimentation rates in different periods. These varies have important relations between sedimentary environment and human activities.