Hydraulic Conductivity from Nuclear Magnetic Resonance Logs in Sediments with Elevated Magnetic Susceptibilities.

This study examined the application of slim-hole nuclear magnetic resonance (NMR) tools to estimate hydraulic conductivity (K ) in an unconsolidated aquifer that contains a range of grain sizes (silt to gravel) and high and variable magnetic susceptibilities (MS) (10 to 10 SI). A K calibration dataset was acquired at 1-m intervals in three fully screened wells, and compared to K estimates using the Schlumberger-Doll research (SDR) equation with published empirical constants developed from previous studies in unconsolidated sediments. While K using published constants was within an order of magnitude of K, the agreement, overprediction, or underprediction of K varied with the MS distribution in each well.