Isotopic microanalysis of seawater strontium in biogenic calcite to assess subsequent rehomogenisation during metamorphism

被引：16

作者：

Adams, CJ

Campbell, HJ

Griffin, WL

机构：

[1] Inst Geol & Nucl Sci, Lower Hutt, New Zealand

[2] Macquarie Univ, Sch Earth Sci, GEMOC Natl Key Ctr, N Ryde, NSW 2109, Australia

来源：

CHEMICAL GEOLOGY | 2005年 / 220卷 / 1-2期

关键词：

ICPMS mass spectrometry; strontium analysis; Sr-87/Sr-86; ratios; biogenic carbonates; Permian; 'Atomodesma';

D O I：

10.1016/j.chemgeo.2005.03.007

中图分类号：

P3 [地球物理学]; P59 [地球化学];

学科分类号：

0708 ; 070902 ;

摘要：

Precise LAM-MC-ICPMS in situ microanalyses of Sr-87/(86) Sr ratios in biogenic calcite of the bivalve 'Atomodesma' are reported for 14 horizons in low-grade metasediments of late Early Permian to late Late Permian age in South Island, New Zealand. 'Atomodesma' shells (and associated skeletal echinoderm calcite) in zeolite and possibly to lower prehnite-pumpellyite mineral facies material yield isotopic data that are interpreted as primary seawater Sr-87/Sr-86 values. Data for higher metamorphic grade (probable upper prehnite-pumpellyite to lawsonite-albite facies) samples consistently show evidence of Sr isotopic homogenisation between 'Atomodesma' calcite and host matrix and thus seawater Sr-87/Sr-86 values are not retained in shell debris under any circumstances. (c) 2005 Elsevier B.V. All rights reserved.

引用

页码：67 / 82

页数：16

共 30 条

[1] Provenance of Permian-Triassic volcaniclastic sedimentary terranes in New Zealand: evidence from their radiogenic isotope characteristics and detrital mineral age patterns [J].