COLLABORATIVE RESEARCH: RESISTIVITY MAPPING OF SUBSURFACE MICROBIAL HABITATS IN THE MCMURDO REGION

Dartmouth College, Hanover NH

Investigators

Abstract

Intellectual Merit: The PIs propose to investigate the feasibility of using airborne Time Domain Electromagnetic (TEM) to map subsurface resistivity in the Antarctic environment. This method offers a non-invasive way to determine the distribution of salinity in subglacial and sub-permafrost environments by distinguishing between high resistivity (glacier ice and bedrock, permafrost) and low resistivity materials (geologic materials saturated by salty water) to a depth of 300 m or greater. The TEM system will be helicopter mounted to generate three-dimensional maps of internal resistivity structure over inaccessible terrain. Deployment the TEM system will be a proof-of-concept to determine whether it can be used to map conductivity and depth of waters in Antarctic subglacial and sub-permafrost environments. These data will help researchers better understand the global function of subglacial microbial ecosystems the nature and extent of subglacial habitats. Coupling geophysical surveying with biogeochemical measurements will provide a unique opportunity to link the role of hydrology and microbial processes in the subsurface environments. The scientific goals of this work are to: 1) Develop flow models of the spatial extent of the brine source and subglacial water movement 2) Measure carbon flux and biomass from the subglacial brine 3) Determine how and why subglacial brine is released exclusively at Blood Falls. Broader impacts: This project will include student training, Antarctic conservation (Blood Falls is being proposed as a new Antarctic Specially Protected Area), and formal outreach developed with an outreach coordinator. The formal outreach plan will be an illustrated book on Antarctic research. To ensure the success of their broader impact goals, all PIs will work closely with Dartmouth College and the WISSARD Project Education and Outreach Coordinator.