Chemolithotrophic life in ultramafic rocks: carbon substrates and pathways enabled by water-rock reactions using field and experimental hydrothermal investigations

甲烷和其他碳氢化合物已经在地球最古老的岩石、陨石和其他行星的大气中被检测到。在地球上，这些碳氢化合物通常被认为是生物活动的产物，因此可以表明今天或数十亿年前生命的存在。因此，对碳氢化合物的研究对研究早期地球上生命的起源和演化，以及在极端环境和其他行星上寻找生命具有重要意义。然而，碳氢化合物也可以通过非生物（非生物）反应产生，但这些碳氢化合物合成的条件还没有得到很好的理解。为了区分生物成因烃和非生物成因烃，必须确定产生非生物成因烃和反应抑制剂的地质条件。因此，必须确定非生物成因烃的独特地球化学指标。在自然环境中，识别非生物成因的碳氢化合物有额外的困难。地下水和它流经的岩石之间的反应，如蛇纹石化（超镁铁岩的水合作用），产生了有利于非生物成因的碳氢化合物生产以及化能无机营养生命的条件。生物反应可以修改或叠加非生物成因的签名。因此，研究碳循环的位置有利于非生物成因的碳氢化合物生产和化能无机营养生命必须检查，以确定这些修改，以确定生命，可以生存在极端的pH值条件下，在蛇纹石化过程中创建，并确定生命的依赖，在这些系统中的蛇纹石化产品。对早期生命和超镁铁质岩石中的水-岩石反应的研究将使加拿大人受益，因为他们将进一步了解地球上生命的演变和非生物成因碳氢化合物的生产。

Methane and other hydrocarbons have been detected in Earth's oldest rocks, meteorites, and the atmospheres of other planets. On Earth, these hydrocarbons are often thought to be products of biological activities, and thus can indicate the presence of life today or billions of years ago. Therefore the investigation of hydrocarbons has implications for the study of the origin and evolution of life on early Earth, and the search for life in extreme environments and on other planets. Hydrocarbons, however, can also be produced by non-biological (abiogenic) reactions, yet the conditions under which these hydrocarbons are synthesized are not well understood. To differentiate between the biogenic and abiogenic hydrocarbons, the geologic conditions for creating abiogenic hydrocarbons and reaction inhibitors must be determined. Subsequently, unique geochemical indicators must be identified for abiogenic hydrocarbons. In natural settings, there is added difficulty identifying abiogenic hydrocarbons. Reactions between groundwater and the rock it flows through, such as serpentinization (the hydration of ultramafic rock), produce conditions amendable for abiogenic hydrocarbon production as well as chemolithotrophic life. Biological reactions can modify or overprint abiogenic signatures. Therefore, studying carbon cycling in locations favourable for abiogenic hydrocarbon production and chemolithotrophic life must be examined to determine these modifications, to identify life that can survive in extreme pH conditions that are created during serpentinization, and to determine the dependence of life in these systems on products of serpentinization. The research into early life and water-rock reactions in ultramafic rocks will benefit Canadians through the advancement of knowledge of life's evolution on Earth and the production of abiogenic hydrocarbons.