TY  - JOUR
A1  - Ziebarth, Malte J.
A1  - von Specht, Sebastian
A1  - Heidbach, Oliver
A1  - Cotton, Fabrice
A1  - Anderson, John G.
T1  - Applying Conservation of Energy to Estimate Earthquake Frequencies from Strain Rates and Stresses
Y1  - 2020
VL  - 125
IS  - 8
JF  - Journal of Geophysical Research: Solid Earth
DO  - 10.1029/2020JB020186
DO  - 10.23689/fidgeo-4941
N2  - Estimating earthquake occurrence rates from the accumulation rate of seismic moment is an established tool of seismic hazard analysis. We propose an alternative, fault-agnostic approach based on the conservation of energy: the Energy-Conserving Seismicity Framework (ENCOS). Working in energy space has the advantage that the radiated energy is a better predictor of the damage potential of earthquake waves than the seismic moment release. In a region, ENCOS balances the stationary power available to cause earthquakes with the long-term seismic energy release represented by the energy-frequency distribution's first moment. Accumulation and release are connected through the average seismic efficiency, by which we mean the fraction of released energy that is converted into seismic waves. Besides measuring earthquakes in energy, ENCOS differs from moment balance essentially in that the energy accumulation rate depends on the total stress in addition to the strain rate tensor. To validate ENCOS, we exemplarily model the energy-frequency distribution around Southern California. We estimate the energy accumulation rate due to tectonic loading assuming poroelasticity and hydrostasis. Using data from the World Stress Map and assuming the frictional limit to estimate the stress tensor, we obtain a power of 0.8 GW. The uncertainty range, 0.3–2.0 GW, originates mainly from the thickness of the seismogenic crust, the friction coefficient on preexisting faults, and models of Global Positioning System (GPS) derived strain rates. Based on a Gutenberg-Richter magnitude-frequency distribution, this power can be distributed over a range of energies consistent with historical earthquake rates and reasonable bounds on the seismic efficiency.
UR  - http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/9287
ER  -