东太平洋海隆之下230钍-238铀不平衡对熔体运移的限制。

Constraints on melt movement beneath the East Pacific Rise from 230Th-238U disequilibrium.

作者信息

Zou Haibo, Zindler Alan, Niu Yaoling

机构信息

Department of Earth and Space Sciences, University of California at Los Angeles, Los Angeles, CA 90095, USA.

出版信息

Science. 2002 Jan 4;295(5552):107-10. doi: 10.1126/science.1064295.

DOI:10.1126/science.1064295

PMID:11778043

Abstract

We report 230Th-238U disequilibrium data on mid-ocean ridge basalts recovered 5 to 40 kilometers off the ridge axis near 9 degrees 30'N of the East Pacific Rise. These data indicate near-symmetrical eruptions of normal mid-ocean ridge basalts (NMORBs) and incompatible element-enriched mid-ocean ridge basalts (EMORBs) as far as 20 kilometers off axis. Our results suggest large-scale subsurface lateral transport of NMORB melt at 19 to 21 centimeters per year and also provide constraints on the petrogenesis of EMORBs of off-axis origin.

摘要

我们报告了在东太平洋海隆北纬9度30分附近、距离洋中脊轴5至40公里处采集的大洋中脊玄武岩的钍-230 - 铀-238不平衡数据。这些数据表明，正常大洋中脊玄武岩（NMORB）和不相容元素富集的大洋中脊玄武岩（EMORB）在距离轴20公里处呈近对称喷发。我们的结果表明，NMORB熔体以每年19至21厘米的速度进行大规模的地下横向运移，同时也对轴外起源的EMORB的岩石成因提供了限制。