An estimate of the juvenile sulfur content of basalt
An estimate of the juvenile sulfur content of basalt
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DOI：
10.1007/bf00386110
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发表时间：
1971-06
影响因子：
3.5
通讯作者：
J. Moore;B. P. Fabbi
中科院分区：
文献类型：
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作者：
J. Moore;B. P. Fabbi
通过 X 射线荧光分析得出，9 个新鲜的海底喷发海洋玄武岩样品的平均硫含量为 107 ppm，38 个海底喷发玄武岩样品的平均硫含量为 680 ppm。这种差异是由于在海底淬火的玄武岩中保留了硫以及通过在表面脱气而导致玄武岩中的硫损失的结果。海底喷发玄武岩的外部玻璃质部分含有800±150 ppm的硫，这个量被认为是地幔玄武岩熔体的新生硫含量的估计值。由于脱气和通过表面裂缝逸出，玄武岩枕的冷却速度较慢的内部相对于边缘被耗尽。深海玄武岩的现有样品并未表明低钾拉斑玄武岩、夏威夷拉斑玄武岩和碱性玄武岩之间的原始硫含量存在差异。分析的火山气体的 H2O/S 比通常低于根据枕状边缘和表面熔岩之间的化学差异确定的表面熔岩损失气体的 H2O/S 比。火山气体中硫相对于水的富集可能是由于火山下方浅层侵入体中硫相对于水的脱气量更大所致。
Sulfur analyses by X-ray fluorescence give an average content of 107 ppm for 9 samples of fresh subaerially-erupted oceanic basalt and 680 ppm for 38 samples of submarine erupted basalt. This difference is the result of retention of sulfur in basalt quenched on the sea floor and loss of sulfur in basalt by degassing at the surface. The outer glassy part of submarine erupted basalt contains 800±150 ppm sulfur, and this amount is regarded as an estimate of the juvenile sulfur content of the basalt melt from the mantle. The slower cooled interiors of basalt pillows are depleted relative to the rims owing to degassing and escape through surface fractures. Available samples of deep-sea basalts do not indicate a difference in original sulfur content between low-K tholeiite, Hawaiian tholeiite, and alkali basalt.The H2O/S ratio of analyzed volcanic gases is generally lower than the H2O/S ratio of gases presumed lost from surface lavas as determined by chemical differences between pillow rims and surface lavas. This enrichment of volcanic gases in sulfur relative to water may result from a greater degassing of sulfur relative to water from shallow intrusive bodies beneath the volcano.