Dynamic NMR Logging Technologies for High-Resolution Measurement of Hydrogeologic Properties and Soil Response

This proposal addresses the challenge of measuring the hydrogeologic response of soils in-situ and at high-resolution to determine flow and storage parameters governing groundwater availability, contaminant fate, and other dynamic subsurface processes. We will develop direct-push instrumentation and methods for efficiently acquiring high-resolution nuclear magnetic resonance (NMR) data in the shallow subsurface. A new high-resolution, miniaturized sensor will engineered that can be deployed in small diameter direct-push rods. In addition to measuring the static NMR response, which conveys porosity, fluid mobility, and pore size, the tool will be integrated with tooling for flow injection around the NMR tool and ancillary dielectric sensors to directly measure dynamic saturation and flow. The Phase 1 research will establish the feasibility of the miniaturized high- resolution NMR sensor as well as the feasibility and sensitivity of the novel flow injection methods. We will design a functional benchtop prototype of the NMR sensor and will validate its sensitivity, resolution, and measurement efficiency. To establish the feasibility and sensitivity of the flow injection and dielectric methods we will perform numerical experiments as well as macro-scale laboratory experiments with an existing downhole NMR tool which will serve as a direct analog for the in-situ subsurface deployment environment. Commercial Applications and Other Benefits: Completion of this technology in Phase II and beyond will deliver high-resolution dynamic NMR as a commercial product for sale, rental, and services in the booming market of subsurface characterization. This technology will make it possible to efficiently and directly measure subsurface properties that have proven difficult to measure with existing methods. The capabilities delivered will be of tremendous value to any company, government, or public agency engaged in contaminated site remediation, soil geotechnical analysis, groundwater resource evaluation, or critical zone research. Ultimately, the technology will benefit worldwide human and ecosystem health, by enabling more effective understanding and management of the subsurface environment.