冲绳海槽DGKS9603孔细粒沉积物元素组合特征及其意义

Variations in sediment provenance and its implications of Core DGKS9603 since the late Quaternary

通过对冲绳海槽DGKS9603孔柱样高密度取样,提取样品中小于2μm的黏土粒级组分,利用ICP-AES进行常、微量元素含量分析后,再经多种方法处理数据,发现该孔沉积物物源时段分明:距今45～43ka以生物源作用为主,距今43～41ka以火山作用为主,距今41 0～11 2ka以陆源作用为主,距今11 2～0 0ka以生物源作用为主.元素和氧化物含量的垂向变化主要受古气候、古环境变化的影响.DGKS9603孔沉积物元素地球化学特征清晰地记录了E3,YD,H1,LGM,H2,H3,H5七次变冷事件,并表明该孔很可能受到了A,B,C三次火山事件的影响.

After using ICP-AES to analyze clay fraction of the samples of Croe DGKS9603 which was taken from the middle Okinawa Trough, the conclusions are obtained as follows: the down variation of the element contents is caused by the paleoclimate and paleoenvironmental evolution; its material source varies clearly, biogenic source is the major source during 45～43 and 11.2～0 ka BP respectively; volcanic source is dominant during 43～41 ka BP and epicontinental source is the most important provenance during 41～11.2 ka BP. Additionally, the seven cold events E3, YD, H1, LGM, H2, H3, H5 are recorded clearly in Core DGKS9603, and the core is probably influenced by three volcanic events A,B,C.