关键词: 南极半岛海区;重矿物;稀土元素;微量元素;统计分析

Abstract:

Based on the analysis and mathematical statistics of quantitative data on both the heavy minerals and their REE (La, Ce, Nd, Sm, Eu, Tb, Yb, Lu), trace (Zr, Hf, Th, Ta, U, Rb, Sr, Zn, Co, Ni, Cr, As, Sc) and major (Fe) elements in the surface sediments in the northwestern sea area of Antarctic Peninsula, the authors find that the heavy minerals as the carriers of REE and trace elements shoud not be overlooked. Q-mode factor analysis of the heavy minerals provides a 3-factor model of the heavy mineral assemblages in the study area, which is mainly controlled by the origin of materials and sea currents. The common factor P1 composed mainly of pyroxene and metal minerals, and common factor P2, composed of hornblende, epidote and accesory minerals, represent two heavy mineral assemblages which are different form each other in both lithological characters and origin of materials. And common factor P3 probably results from mixing of two end members of the above-mentioned assemblages. R-mode group analysis of the heavy minerals Indicates that there are two heavy mineral groups in the sea area, which are different from each other in both genesis and origin of materials. With the help of R-mode analysis, 22 elements are divided into 3 groups and 9 subgroups. These element assemblages show that they are genetically related and that they are different in geochemical behaviors during diagenesis and mineral-forming process. In addition, the relationship between the heavy mineral assemblages and the element subgroups is also discussed.