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This dataset contains surface nuclear magnetic resonance (NMR) geophysical soundings acquired on five drained lake basins and two control sites on terrestrial upland permafrost (primary surface sites) during spring fieldwork 2015 - 2016. Measurements were made using a Vista Clara GMR (Mukilteo, Washington, Unites States of America) with a circle coincident transmitter/receiver loop either 75 meters (m) or 90 m diameter. Raw data for nine soundings are provided in the proprietary format created by the instrument, and results after processing and inversion with the GMR software (Mukilteo, Washington, Unites States of America; Walsh, 2008) are included as tabular values. The purpose of this research is to identify unfrozen bodies or taliks below drained lake basins to better understand the process of permafrost aggradation after lake drainage. Surface NMR is the only non-invasive geophysical method that is able to directly detect unfrozen water as it measures the response of hydrogen protons on liquid water (Walsh, 2008). Walsh, D. O. (2008). Multi-channel surface NMR instrumentation and software for 1D/2D groundwater investigations. Journal of Applied Geophysics, 66(3–4), 140–150. https://doi.org/10.1016/j.jappgeo.2008.03.006
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Transient Electromagnetic (TEM) Soundings on Drained Permafrost Lake Basins, North Slope, Alaska, 2019
This dataset contains transient electromagnetic (TEM) geophysical soundings acquired on drained permafrost lake basins at the North Slope of Alaska during spring fieldwork in 2019. Measurements were made using an ABEM WalkTEM with a 1600 meter squared (m^2) transmitter loop, a 200 m^2 receiver loop, and a 5 m^2 receiver loop, all in a center-nested configuration. Raw data for 15 soundings are provided in the Universal Sounding Format (USF), and results after processing (smooth constraint) with SPIA (GuidelineGeo/ABEM/Aarhus Hydrogeopyhsics) inversion software are included as tabular geolocated values. A KML indicating point location of the center of each sounding is also provided.
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- Award ID(s):
- 1806213
- PAR ID:
- 10303023
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- geophysics transient electromagnetic time domain electromagnetic lakes permafrost thermokarst hydrogeophysics
- Format(s):
- Medium: X Other: text/xml
- Sponsoring Org:
- National Science Foundation
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