Detecting unfrozen sediments below thermokarst lakes with surface nuclear magnetic resonance

摘要: [1] A talik is a layer or body of unfrozen ground that occurs in permafrost due to an anomaly thermal, hydrological, hydrochemical conditions. Information about geometry important for understanding regional surface water and groundwater interactions as well sublacustrine methane production thermokarst lakes. Due the direct measurement content, nuclear magnetic resonance (NMR) promising geophysical method noninvasively estimating dimensions. We made NMR measurements on lakes terrestrial near Fairbanks, Alaska, confirmed our results using limited measurements. At 8 m deep lake, we observed thaw bulb at least 22 m below surface; 1.4 m detected extending between 5 6 m surface. Our study demonstrates value may have cryosphere studies lake hydrology their related role carbon cycle.