Helium/heat ratios and deposition temperatures of sulphides from the ocean floor
Helium/heat ratios and deposition temperatures of sulphides from the ocean floor
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DOI：
10.1038/357581a0
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发表时间：
1992-06
期刊：
影响因子：
64.8
通讯作者：
G. Turner;F. Stuart
中科院分区：
文献类型：
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作者：
G. Turner;F. Stuart
热液喷口上方海洋中过量的he浓度与温度之间的相关性已被用于联系来自上地幔的热和稀有气体的通量。因为热量和氦都是由铀和钍的衰变产生的，所以观测到的氦/热比携带着地幔内部和扩散中心的热量和质量传递过程的信息。沉积在海底的硫化物和其他沉积物以流体包裹体的形式捕获了热液溶液：我们在这里证明，东太平洋隆起21°N的硫化物真空挤压释放的氦和氩同位素与当代喷口流体中的氦和氩同位素相似。这一观察结果表明，通过测量从古代海底沉积物中收集的样本，应该有可能将对喷口流体3he /4He和氦/热比的研究扩展到过去。
CORRELATIONS between excess3He concentration and temperature in the ocean above hydrothermal vents have been used1,2to relate the fluxes of heat and noble gases from the upper mantle. Because heat and4He are both produced by the decay of uranium and thorium, the observed helium/heat ratios carry information on thermal and mass transport processes within the mantle and at spreading centres. Sulphide and other deposits precipitated on the sea floor trap the hydrothermal solutions as fluid inclusions: we demonstrate here that helium and argon isotopes released byin vacuocrushing of sulphides from 21° N on the East Pacific Rise are similar to those in contemporary vent fluids. This observation suggests that it should be possible to extend the study of vent fluid3He/4He and helium/heat ratios back in time by measuring samples collected from ancient sea-floor deposits.