南海ODP1144孔微玻璃陨石物理化学性质及母源物质的复杂性

ODP 184航次 114 4孔位于南海北部陆缘 (2 0°3.18′N ,117°2 5 .14′E ,水深 2 0 37m) ,在岩心样品中发现的微玻璃陨石主要赋存于 386 .17～ 386 .2 7mcd处 ,这些玻璃陨石主要以球形和椭球形为主 ,可见泪滴状、马鞍形、扁豆形、圆盘形、哑铃形、翼形、异形等形态和不规则状碎片。通过微玻璃陨石主量元素电子探针分析 ,并用Harker图解讨论了主量元素氧化物之间的相关性 ,同时结合Niggli参数进一步深入探讨微玻璃陨石的母源物质特征。研究结果表明 ,ODP114 4孔微玻璃陨石属于澳亚散落区内的普通型微玻璃陨石 ,其母源物质成分复杂 ,可能有两种或两种以上的物质组成 ,一种可能是化学成分没有太大变化的碎屑沉积岩 ,另一种可能是粘土及杂砂岩等。

PHYSICAL PROPERTIES, MAJOR ELEMENT COMPOSITION AND COMPLICITY OF PARENT MATERIAL OF MICROTEKTITES FROM ODP CORE 1144

ODP Core 1144 (20°3.18′N,117°25.14′E,water depth 2037m) is located on the northern margin of the South China Sea. Many microtektites were collected from sediment samples at depths of 386.17—386.27mcd. They are mostly spherical and oval in shape, in addition to teardrops, saddles, buns, dumbbells, disc-shapes and fragments. The major elements of these microtektites were measured by microprobe. According to Harker plots and Niggli parameters of major element composition, our conclusion is that microtektites from ODP Core 1144 are resultant from Australian normal microtektites. The parent materials are complicated in composition. One of them may be some clastic sediment, which has not yet been chemically altered. Other one or two components involved were probably derived from clay and sandstone.