...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Geochemical Journal >Monitoring of temporal and spatial variations in fumarole helium and carbon dioxide characteristics at Poas and Turrialba volcanoes, Costa Rica (2001-2009)
【24h】

Monitoring of temporal and spatial variations in fumarole helium and carbon dioxide characteristics at Poas and Turrialba volcanoes, Costa Rica (2001-2009)

机译：监测哥斯达黎加Poas和Turrialba火山的喷气孔氦气和二氧化碳特性的时空变化

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We report results of a 9-year monitoring program that took place from 2001 to 2009 of the helium and carbon isotope (~3He/~4He, δ~(13)C) and relative abundances ratios (CO_2/~3He) of fumarole sites at Pods and Turrialba volcanoes, Costa Rica. Over the monitoring period, helium isotopes (~3He/~4He), δ~(13)C_((CO2)) and CO_2/~3He values varied between 6.7-7.6 R_A (where R_A = 1.4 x 10~(-6)), -5.5 to -1.3‰ (vs. PDB) and 8.2-59.5 (x10~9), respectively, at Pods Volcano. Corresponding values for Turrialba Volcano were 6.9-8.0 R_A, -4.4 to -2.7‰ and 9.4-19.6 (x10~9), respectively. Notably, fumarole sites at both volcanoes underwent changes in temperature, intensity and areal extent during the 9-year period, and Pods Volcano experienced hydrophreatic eruptions and structural damage induced by a nearby earthquake. At both volcanoes, there were significant and sympathetic temporal changes involving all three geochemical parameters—notably in 2001 and 2006 at Poas and in 2001 and between 2005-2007 at Turrialba. We dismiss increased hydrothermal interaction, magma degassing and calcite precipitation as likely causes of the observed variations. Instead, by ascribing endmember compositions to the three principal contributors to the CO_2 inventory—mantle wedge as well as limestone and organic (sedimentary) carbon (both slab and crust derived)—we show that changes in observed He-CO_2relationships mainly reflect enhanced crustal contributions of CO_2 and increased inputs from magma degassing. Such changes in the relative roles of crust and magma as suppliers of CO_2 are readily apparent in the He-CO_2 temporal record. This work supports calls for long-term geochemical monitoring to be included within hazard assessment and mitigation studies at active volcanoes.
机译：我们报告了从2001年到2009年进行的为期9年的监测计划的结果，该计划的结果是烟熏地点的氦和碳同位素（〜3He /〜4He，δ〜（13）C）和相对丰度比（CO_2 /〜3He）在哥斯达黎加的Pods和Turrialba火山。在监测期间，氦同位素（〜3He /〜4He），δ〜（13）C _（（CO2））和CO_2 /〜3He值在6.7-7.6 R_A之间变化（其中R_A = 1.4 x 10〜（-6） ），波德斯火山分别为-5.5至-1.3‰（vs.PDB）和8.2-59.5（x10〜9）。图里亚尔巴火山的对应值分别为6.9-8.0 R_A，-4.4至-2.7‰和9.4-19.6（x10〜9）。值得注意的是，在这9年的时间里，两个火山的喷气孔位置都经历了温度，强度和面积范围的变化，而Pods火山经历了水溶喷发和附近地震引起的结构破坏。在这两个火山上，都发生了显着且同情的时间变化，涉及到所有三个地球化学参数-尤其是在2001年和2006年在Poas，在2001年以及2005-2007年在图里亚尔巴。我们认为增加的热液相互作用，岩浆脱气和方解石沉淀是观察到的变化的可能原因。相反，通过将最终成员的组成归因于CO_2清单的三个主要贡献者（地幔楔以及石灰石和有机（沉积）碳（板状和地壳两者）），我们表明观察到的He-CO_2关系的变化主要反映出地壳贡献的增加CO_2的增加和岩浆脱气增加的投入。在He-CO_2时间记录中，地壳和岩浆作为CO_2的提供者的相对作用的这种变化很明显。这项工作支持将长期地球化学监测纳入对活动火山的危害评估和缓解研究的呼吁。

著录项

相似文献

  • 外文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号