Project Title: Nitrogen as a building block of life in subsurface serpentinizing systems and early life on Earth
In recent years, serpentinization – the water/rock reactions coupling oxidation of ferrous iron to the generation of hydrogen – has been hypothesized to be central to the emergence of life. These reactions in ultramafic rocks in highly alkaline hydrothermal settings, can generate methane and other simple organic compounds. Together with the proton and redox gradients, they create conditions highly conducive to chemosynthetic microbial life. However, missing in these considerations are the sources of nitrogen – an element essential to all life on Earth, as required in the building of proteins and nucleic acids, and sometimes also used in respiration to acquire energy. It remains unclear how microorganisms living in serpentinizing systems obtain their nitrogen, and/or how this nutrient is cycled from one form to another, or from one group of organisms to another.
This project aims to characterise active microbial nitrogen cycling within serpentinizing systems, primarily in the Samail ophiolite, Oman, the world’s largest peridotite massif, as well as to trace the origin of nitrogen used by these subsurface microbes. How the above may alter along fluid flow paths across sharp pH and redox gradients, and how nitrogen-cycling reactions may power life in a system simulating early life on Earth will be investigated.
An interdisciplinary approach will be used to tackle the research questions. This will include geochemical measurements and experimentation with deep subsurface biosphere, peridotites and associated fluids, flux measurements of inorganic/ organic nutrients and state-of-the-art stable isotope analyses and tracer experiments. These would be combined with genomics- and transcriptomics- based molecular analyses on the resident microbial communities, as well as microscopy-based techniques like fluorescence in situ hybridisation and Raman microspectroscopy to examine their spatial distribution in fluids, within fractures or on surfaces of rock samples. The student will play an active role in the field campaign of the Samail ophiolite, Oman. It hosts well-exposed regions of active peridotite alteration, characterized by numerous alkaline springs and abundant calcite travertine terraces and is thus ideal for the study of low-temperature serpentinizing system.
This project will use the existing sampling sites and infrastructures established in the ICDP funded Oman Drilling Project (http://www.omandrilling.ac.uk/) targeting the Samail Ophiolite, thus effects of microbial activities on subsurface microbial nitrogen cycling can be interpreted in a much wider context.
The INSPIRE DTP programme provides comprehensive personal and professional development training alongside extensive opportunities for students to expand their multi-disciplinary outlook through interactions with a wide network of academic, research and industrial/policy partners. The student will be registered and hostedat the University of Southampton. The student will join a multidisciplinary research team, with exposure to a wide variety of biogeochemical and molecular biological techniques, and how these analyses can be integrated together to solve questions in geobiology and geochemistry. Full training will be provided in the range of techniques required, including field sampling and experimentation with fluid samples, stable isotopic measurements, epifluorescence microscopy and Raman microspectroscopy, as well as meta-omics analyses enabled by next-generation-sequencing. The student must be fit and able to join research expeditions (land-/ship- based) and have an aptitude for practical fieldwork.
Further inquiries on the project may be directed to Dr. Phyllis Lam (P.Lam@southampton.ac.uk).
For more information on the INSPIRE DTP studentships at the GSNOCS and application procedures, please follow the link - https://noc.ac.uk/gsnocs/project/nitrogen-building-block-life-subsurface-serpentinizing-systems-and-early-life-earth