Asian continental nature of87Sr/86Sr ratios in north central Pacific sediments
Asian continental nature of87Sr/86Sr ratios in north central Pacific sediments
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DOI：
10.1016/0012-821x(95)00048-h
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发表时间：
1995-06
影响因子：
5.3
通讯作者：
Y. Asahara;Tsuyoshi Tanaka;H. Kamioka;A. Nishimura
中科院分区：
文献类型：
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作者：
Y. Asahara;Tsuyoshi Tanaka;H. Kamioka;A. Nishimura
测定了太平洋152个深海和大陆架表层沉积物样品中硅酸盐碎屑的锶同位素组成，以追踪其来源。锶同位素空间变化的主要特征及其解释可概括为：(1)太平洋沉积物的87Sr86Sr平均比值(0.7112)低于大西洋沉积物(0.7166；0.704-0.743)，幅度较小(0.703-0.724)。许多西太平洋火山与年轻的大陆地壳一起向太平洋提供了低87Sr86Sr比的物质，与之形成对比的是，巨大的古老克拉通地壳向大西洋提供了高锶比的物质。(2)中北部太平洋(0.711-0.719)的87Sr86Sr比值较高。伊豆-小川岛弧和马里亚纳弧向西太平洋提供了低87Sr86Sr物质，但在更远的东部，来自亚洲大陆的中纬度西风带(87Sr86Sr=约0.720)携带的丰富黄土供应主导了中北部太平洋。
Strontium isotopic compositions were determined for silicate detritus in 152 deep-sea and continental shelf surface sediment samples from the Pacific Ocean to trace their provenance. The major characteristics of the spatial variation of the Sr isotopes and the interpretation of this variation may be summarized as follows: (1) Sediments in the Pacific have a lower average87Sr86Sr ratio (0.7112) with a narrower range (0.703–0.724) than in the Atlantic (0.7166; 0.704–0.743). Many western Pacific volcanoes together with young continental crust supply material with low87Sr86Sr ratios to the Pacific, in contrast to the large old cratonic crust that supplies material with high Sr ratio to the Atlantic. (2) The87Sr86Sr ratio is high in the north central Pacific (0.711–0.719). The Izu-Ogasawara and Mariana arcs supply low87Sr86Sr material to the western Pacific, but farther to east the abundant supply of loess carried by middle-latitude westerlies from the Asian continent (87Sr86Sr = ca. 0.720 ) dominates the north central Pacific.