Periodic Hydraulic Tests in a Fractured Crystalline Bedrock

• Main Author: Cole, Matthew C.
• Language: EN
• Published: California State University, Long Beach 2018
• Subjects: Geology|Hydrologic sciences
• Online Access: http://pqdtopen.proquest.com/#viewpdf?dispub=10742695

<p>A better understanding of groundwater flow through bedrock fractures is critical to applications involving heat and solute transport. Pumping tests performed to characterize these systems are often ill-suited because the radius of penetration quickly expands beyond the inter-well distance, gaining information beyond the well pair of interest. Periodic hydraulic tests allow the radius of penetration to be controlled by the frequency of oscillation, and testing at multiple frequencies gives parameter estimates for a range of spatial scales. Periodic pumping tests were performed at the Mirror Lake experimental fractured rock hydrology field site in New Hampshire. Results suggest a more complex, 3D network of connectivity than previously indicated by constant rate pumping tests. The relative degree of connectivity, given by diffusivity, corresponds to early-time response seen in the constant rate test. This confirms that the periodic tests investigated at a smaller penetration radius than the steady response from constant pumping.