Collaborative Research: Evolution of Subsurface Microbe-Rock-Fluid Systems

This project investigates how changes to the Earth’s surface over geologic time have affected the deep biosphere, the geologic and climatic factors that favor or limit the potential for subsurface microbial life, and the history of microbial life and its relationship to fluids and fluid-rock reactions. Knowledge of how water and other fluids flow at great depths beneath the Earth’s surface, and how this supports and affects life deep within the Earth’s crust, is very limited.

Yet, understanding the ways that these subsurface fluids, rocks, and microbes interact and evolve over geologic time is essential for sustainable use of water, mineral, and energy resources and disposal of their unwanted by-products. Results will identify specific time periods in the geologic past and locations within the Earth’s crust where subsurface conditions promoted microbial activity and provide insights into the long-term history of microbial habitability in the planet’s deep biosphere.

This project will train several graduate students, help to recruit and retain first-generation, low-income, community college, and under-represented minority undergraduate students, engage K-12 students through development of Earth Science curriculum, and share research results more broadly with the general public through educational videos.

This project will develop an interdisciplinary framework and approaches necessary to track the evolution of subsurface microbe-rock-fluid systems in the upper few kilometers of the Earth’s crust. The research will explore the interconnections between fluid circulation, fluid-rock reactions, and subsurface microbial habitability, and make predictions regarding the evolution of these conditions over geologic time.

The project will identify the drivers and permeability changes promoting convergence of compositionally disparate fluids and rocks that alter subsurface redox gradients, thermodynamic conditions, and metabolic potentials for microbial activity.The Paradox and Rio Grande Rift basins in the southwestern US will be the field sites used to develop and test models that can be applied to other subsurface microbe-rock-fluid systems. Research outcomes will generate critical information on the lower boundaries of the active hydrologic cycle and deep microbial ecosystems required for effective management of subsurface water, mineral, and energy resources and storage of alternative energy and waste-products.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.