东南极拉斯曼丘陵的沉积

A STUDY ON THE SEDIMENTS OF THE LAKSEMANN HILLS,EAST ANTAKCTICA

拉斯曼丘陵区风化过程微弱、初始，沉积物地球化学指数与母岩高度相似。沉积物搬运距离短，且风力的混合扰动作用强烈，沉积颗粒级配过程、粒度参数、化学组份均反映这一特征。丘陵西部沉积物保存较好，东部区则受外力明显的改造。各类沉积物１０ｍｍ以下颗粒均值（Ｍ＿２（φ））介于中砂到粗砂范围内；分选差，样品标准差δ多集中在２．０附近；随着Ｍ＿ｚ（φ）的增大，频率曲线变尖陡，型式愈近正态分布曲线；同时，δ也随Ｍ＿２（φ）的增大而升高。各类沉积物中均含少量的悬浮物，含量介于５—１０％之间。

Larsemann Hills,sedimentary characteristicsAbstract The weaqthering processes are very weak and original on the hills,The geochemical in-dexes of sedmients and rocks are very similar. Sediments were transported in a short dis-tance,and were mixed with,the aeolian deposits. This fact has been confirmed by grain-size distributions,grain-size parameters and geochemical compositions. The sediments on the westhills still remains an original condition,and the sediments on the east hills have been trans-formed obviously.The sediments with the mean diameters less than 10mm are middle sizesands and coarse sands.The suspended grains are very small which make up only up only 5-10%.