Assessing the geochemical signatures of abiogenically dominated methane sources

评估非生物成因甲烷来源的地球化学特征

• 批准号: 76326059
• 负责人: Professor Dr. Jens Fiebig
• 金额: --
• 依托单位: Institute of Earth Surface Dynamics (IDYST)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2008
• 资助国家: 德国
• 起止时间: 2007-12-31 至 2011-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/76326059?language=en
• 关键词: Assessing; geochemical; signatures; abiogenically; dominated

Methane (CH4) and the higher hydrocarbons are of particular interest for society. The majority of naturally occurring hydrocarbons is assumed to derive from biogenic (thermogenic and microbial) sources. Unambiguous evidence for abiogenic reduction of CO2 to hydrocarbons within the Earth s crust has been lacking. Recently, we demonstrated the occurrence of abiogenic production of CH4 in three subduction-related bi-phase-hydrothermal systems of the Mediterranean region. These localities offer a great opportunity to study the abiogenic signature of these hydrocarbons in terms of the classical chemical and isotopic parameters, which are commonly used to distinguish thermogenic from microbial sources. Comparison of theoretical and empirical data with measured data will enable a) an estimate of the extent that biogenic sources contribute to overall hydrocarbon production in abiogenically dominated systems, and b) an assessment of the extent that abiogenically dominated sources might have been erroneously classified as biogenic. In search of new indicators for abiogenically dominated sources, we will investigate the factors that exert control on the occurrence of aromatic and unsaturated hydrocarbons in these volcanic-hydrothermal systems.

甲烷（CH4）和高级烃是社会特别感兴趣的。大多数天然存在的碳氢化合物被认为是来自生物源（生热和微生物）。在地壳内，二氧化碳非生物还原为碳氢化合物的非生物证据一直缺乏。最近，我们证明了发生在地中海地区的三个俯冲相关的双相热液系统的非生物生成的CH4。这些地方提供了一个很好的机会来研究这些烃类的经典化学和同位素参数，这是常用的区分产热微生物来源的非生物签名。理论和经验数据与实测数据的比较将使得能够a）估计生物源对非生物源主导的系统中的总烃生产的贡献程度，和B）评估非生物源主导的源可能被错误地分类为生物源的程度。在寻找非生物为主的来源的新指标，我们将调查的因素，发挥控制这些火山热液系统中的芳烃和不饱和烃的发生。