Grain size characteristics of surface sediments on the Prydz Bay shelf , East Antarctica , together with dynamic environment , were analyzed to illustrate sediment types , compositions and relevant glaciomarine sedimentation .The surface sediments were classified into nine types:gravel, muddy sandy gravel, gravelly mud, gravelly muddy sand, slightly gravelly mud , slightly gravelly muddy sand , sand , sandy silt , and silt .The study area could be divided in-to two sections based on sediment grain size and topography , a gravelly mud section in the east of the bay and a gravelly sand section in the west .In the eastern gravelly mud section , including Four Ladies Bank , the Svenner Channel , the Prydz Channel and the Amery Basin , sedimentation is mainly controlled by marine circulation with lit-tle contribution from iceberg , and then sediments are relatively fine and contain a large amount of clay and fine silt . In contrast , the coarse-grained sediments in the western gravelly sand section , including the Fram Bank and the Amery Ice Shelf front , are products of iceberg , current and Amery ice shelf with an exception of fine-grain sediment occurring in the polynya .%基于对普里兹湾陆架表层沉积物粒度分析，结合海区动力环境特点，初步探讨了考察区类型、组成及冰海沉积作用特点。研究区表层沉积物大体可分为：砾（ G）、泥质砂质砾（ msG）、砾质泥（ gM）、砾质泥质砂（ gmS）、含砾泥（（g）M）、含砾泥质砂（（g）mS）、砂（S）、砂质粉砂（sZ）和粉砂（Z）九种类型。依据沉积物粒度特征与地形变化，可将研究区划分为东部含砾泥质区和西部含砾砂质区。在东部含砾泥质区，包括四夫人浅滩、Svenner水道区、普里兹水道区和埃默里海盆区，沉积作用主要受海流影响，冰筏碎屑的影响有限，沉积物总体较细，粘土和细粉砂含量较高，粗粉砂和砂含量较低。在西部含砾砂质区，包括弗拉姆浅滩和埃默里冰架前缘，沉积作用受冰山、埃默里冰架和海流的共同影响，沉积物中粘土含量较低，砂和砾石含量较高，但也有个别站位可能受冰间湖的影响，沉积物粒度偏细。
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