Collaborative Research: Geothermal Fluxes of Solutes, Heat, and Carbon Dioxide to the River System of Central Nepal

合作研究：尼泊尔中部河流系统的溶质、热量和二氧化碳地热通量

• 批准号: 0090116
• 负责人: Robert Darling
• 金额: $ 1.2万
• 依托单位: SUNY College at Cortland
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-02-01 至 2004-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0090116&HistoricalAwards=false
• 关键词: Collaborative; Research; Geothermal; Fluxes; Solutes

0090116DarlingIntegrated study of hot spring and stream chemistry in major tributaries of the Narayani river system of central Nepal, and stable isotope and fluid inclusion studies of associated hydrothermal vein material is underway. Data on the sources of solutes and sediments in Himalayan rivers indicate that active geothermal systems near the Main Central Thrust and in the Thakola graben are important sources of heat and solutes (including Na, K, Ca, Cl, Ge, Si and Sr), and release CO2 from metamorphic decarbonation reactions at depth 13C values from hot spring fluids are as high as +130/00, indicating a metamorphic source of CO2. About 25% of the flux of dissolved K and Sr, 12-15% of dissolved Si, and 90% of Cl at the confluence with the Trisuli river are derived from hydrothermal sources near the MCT. The heat loss from the surface springs is near 80 m W/m2 averaged over the area of the High Himalayan Crystalline series in the Marsyandi basin.This data indicate that geothermal activity along the MCT has a significant impact on geochemical and heat fluxes in the Himalaya.Data from hot springs and tributaries in the major tributary drainage of the Narayani (Kali Gandaki, Seti, Marsyandi, Bhuri, and Trisuli rivers) are being used to construct a chemical and water flux mass balance for the hydrothermal systems. Chemical mass balance of conservative tracers including SO4 /=Cl- and Ge/Se will be used to estimate hydrothernal contributions to river fluxes. Fluid inclusion and stable isotope analysis of undeformed "contribution to river Fluxes. Fluid inclusion and stable isotope analysis of undeformed "post-metamorphic" quartz and calcite veins will be used to estimate reservoir conditions, water-rock ratios, and local geothermal gradients in the convective system. The study is providing important data-driven estimate of geothermal heat flow and carbon degassing from the Himalaya that will help resolve difficulties with current Himalayan river budgets for radiogenic Sr and other dissolved species and new understanding to both our knowledge of Himalayan tectonic processes and how they impact geochemical fluxes.

0090116达林正在对尼泊尔中部纳拉亚尼河系统主要支流的温泉和溪流化学进行综合研究，并对相关热液脉物质进行稳定同位素和流体包裹体研究。 喜马拉雅河流中溶质和沉积物来源的数据表明，主中央冲断层附近和塔科拉地堑中的活跃地热系统是热量和溶质的重要来源（包括Na、K、Ca、Cl、Ge、Si和Sr），并在深度13 C值处从热泉流体的变质脱碳酸反应释放CO2，表明是二氧化碳的变质源 约25%的溶解K和Sr，12-15%的溶解Si，和90%的Cl在与Trisuli河汇合处的流量来自于MCT附近的热液源。 Marsyandi盆地高喜马拉雅结晶系列地区地表温泉的平均热损失接近80 m W/m2。这些数据表明，沿着MCT的地热活动对喜马拉雅地区的地球化学和热通量有重大影响。来自纳拉亚尼主要支流流域的温泉和支流的数据（Kali Gandaki，Seti，Marsyandi，Bhuri和Trisuli河）正在被用来构建热液系统的化学和水通量质量平衡。 保守的示踪剂，包括SO 4/=Cl-和Ge/Se的化学质量平衡将被用来估计水热贡献的河流通量。 未变形流体包裹体和稳定同位素对河流流量的贡献。 流体包裹体和稳定同位素分析的未变形的“后变质”石英和方解石脉将被用来估计水库条件，水岩比，和当地的地热梯度的对流系统。 这项研究提供了重要的数据驱动的估计地热热流和碳脱气从喜马拉雅山，这将有助于解决困难与目前的喜马拉雅河预算放射性锶和其他溶解的物种和新的理解，我们的知识喜马拉雅构造过程和它们如何影响地球化学通量。