2020
Schmidt, Logan; Rempe, Daniella M.
Quantifying Dynamic Water Storage in Unsaturated Bedrock with Borehole Nuclear Magnetic Resonance Journal Article
In: Geophysical Research Letters, vol. 47, no. 22, pp. e2020GL089600, 2020.
Abstract | Links | BibTeX | Tags: Critical Zone, ERCZO, hydrogeophysics, neutron moderation nuclear magnetic resonance, vadose zone, water storage
@article{Schmidt2020,
title = {Quantifying Dynamic Water Storage in Unsaturated Bedrock with Borehole Nuclear Magnetic Resonance},
author = {Logan Schmidt and Daniella M. Rempe},
doi = {10.1029/2020GL089600},
year = {2020},
date = {2020-11-02},
journal = {Geophysical Research Letters},
volume = {47},
number = {22},
pages = {e2020GL089600},
abstract = {Quantifying the volume of water that is stored in the subsurface is critical to studies of water availability to ecosystems, slope stability, and water‐rock interactions. In a variety of settings, water is stored in fractured and weathered bedrock as rock moisture. However, few techniques are available to measure rock moisture in unsaturated rock, making direct estimates of water storage dynamics difficult to obtain. Here, we use borehole nuclear magnetic resonance (NMR) at two sites in seasonally dry California to quantify dynamic rock moisture storage. We show strong agreement between NMR estimates of dynamic storage and estimates derived from neutron logging and mass balance techniques. The depths of dynamic storage are up to 9 m and likely reflect the depth extent of root water uptake. To our knowledge, these data are the first to quantify the volume and depths of dynamic water storage in the bedrock vadose zone via borehole NMR.},
keywords = {Critical Zone, ERCZO, hydrogeophysics, neutron moderation nuclear magnetic resonance, vadose zone, water storage},
pubstate = {published},
tppubtype = {article}
}
Quantifying the volume of water that is stored in the subsurface is critical to studies of water availability to ecosystems, slope stability, and water‐rock interactions. In a variety of settings, water is stored in fractured and weathered bedrock as rock moisture. However, few techniques are available to measure rock moisture in unsaturated rock, making direct estimates of water storage dynamics difficult to obtain. Here, we use borehole nuclear magnetic resonance (NMR) at two sites in seasonally dry California to quantify dynamic rock moisture storage. We show strong agreement between NMR estimates of dynamic storage and estimates derived from neutron logging and mass balance techniques. The depths of dynamic storage are up to 9 m and likely reflect the depth extent of root water uptake. To our knowledge, these data are the first to quantify the volume and depths of dynamic water storage in the bedrock vadose zone via borehole NMR.