TY  - JOUR
A1  - Mohr, Christian Heinrich
A1  - Manga, Michael
A1  - Wang, Chi-yuen
A1  - Kirchner, James W.
A1  - Bronstert, Axel
T1  - Shaking water out of soil
JF  - Geology
N2  - Moderate to large earthquakes can increase the amount of water flowing in streams. Previous interpretations and models assume that the extra water originates in the saturated zone. Here we show that earthquakes may also release water from the unsaturated zone when the seismic energy is sufficient to overcome the threshold of soil water retention. Soil water may then be released into aquifers, increasing streamflow. After the M8.8 Maule, Chile, earthquake, the discharge in some headwater catchments of the Chilean coastal range increased, and the amount of extra water in the discharge was similar to the total amount of water available for release from the unsaturated zone. Assuming rapid recharge of this water to the water table, a groundwater flow model that accounts for evapotranspiration and water released from soils can reproduce the increase in discharge as well as the enhanced diurnal discharge variations observed after the earthquake. Thus the unsaturated zone may play a previously unappreciated, and potentially significant, role in shallow hydrological responses to earthquakes.
Y1  - 2015
U6  - https://doi.org/10.1130/G36261.1
SN  - 0091-7613
SN  - 1943-2682
VL  - 43
IS  - 3
SP  - 207
EP  - 210
PB  - American Institute of Physics
CY  - Boulder
ER  -