Helium Isotopes in Fluids of the Baykal Rift Zone
Helium Isotopes in Fluids of the Baykal Rift Zone
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贝加尔裂谷带流体中的氦同位素
DOI：
10.1080/00206819309465522
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发表时间：
1993
影响因子：
2.6
通讯作者：
M. Khutorskoy
中科院分区：
文献类型：
--
作者：
B. Polyak;E. Prasolov;I. Tolstikhin;S. V. Kozlovtseva;V. Kononov;M. Khutorskoy
测量了西伯利亚南部和蒙古北部34个地点地下流体中氦的同位素组成，3He/4He比值从放射性成因（~ 10−8）到地幔（~ 10−5）不等。在大多数情况下，伊尔库茨克露天剧场的碳氢化合物流体只含有放射性氦；这是圆形剧场与古代平台的区别。相比之下，来自贝加尔湖裂谷带的流体是通过氦的存在和地幔成分来区分的；在Tunka盆地的热流体中，这一成分几乎达到100%。CH4/3He和(CO2 + CH4)/3He比值表明裂谷带流体中的甲烷和二氧化碳可能部分为岩浆成因；另一方面，在伊尔库茨克露天剧场，这种气体纯粹是地壳作用的结果。3He/4He比值沿贝加尔湖裂谷带长度变化，其值的减小与热流的减小、地壳厚度的增加和裂谷盆地尺度的减小有关。
The isotopic composition of helium in subterranean fluids from 34 locations in southern Siberia and northern Mongolia has been measured- The ratio 3He/4He ranges from radiogenic (∼10−8) to mantle (∼10−5) values. For the most part, the hydrocarbon fluids of the Irkutsk amphitheater contain only radiogenic helium; this distinguishes the amphi-theater from ancient platforms. In contrast, fluids from the Baykal rift zone are distinguished by the presence of helium with a mantle component; this component reaches almost 100% in thermal fluids in the Tunka basin. The ratios CH4/3He and (CO2 + CH4)/3He suggest that the methane and carbon dioxide in the rift zone fluids may be partially magmatogenic; in the Irkutsk amphitheater, on the other hand, such gases originated as a result of purely crustal processes. The 3He/4He ratio varies along the length of the Baikal rift zone, with decreasing values correlating with decreasing heat flow, increasing thickness of crust, and decreasing dimensions of rift basins.