Seismogeodetic P-wave Amplitude: No Evidence for Strong Determinism
D E Goldberg1,2, D Melgar2, Y Bock1
1Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography University of California San Diego San Diego California USA.
Abstract:
Whether the final properties of large earthquakes can be inferred from initial observations of rupture (deterministic rupture) is valuable for understanding earthquake source processes and is critical for operational earthquake and tsunami early warning. Initial (P-wave) characteristics of small to moderate earthquakes scale with magnitude, yet observations of large to great earthquakes saturate, resulting in magnitude underestimation. Whether saturation is inherent to earthquake dynamics or rather is due to unreliable observation of long-period signals with inertial seismic instrumentation is unclear. Seismogeodetic methods are better suited for broadband observation of large events in the near-field. In this study, we investigate the deterministic potential of seismogeodetically derived P-wave amplitude using a dataset of 14 medium-to-great earthquakes around Japan. Our results indicate that seismogeodetic P-wave amplitude is not a reliable predictor of magnitude, opposing the notion of strong determinism in the first few seconds of rupture.
Related Concept Videos
Variation in Acceleration due to Gravity near the Earth's Surface
The difference between the true and apparent weights is proportional to the square of the Earth's...
Measuring Acceleration Due to Gravity
A simple pendulum can be described as a point mass and a string. Meanwhile, a physical pendulum is any object whose oscillations are similar to a simple pendulum, but cannot be modeled as a point mass on a string because its mass is distributed over a larger area. The behavior of a physical pendulum can be modeled using the principles of...
The Principle of Superposition and the Gravitational Field
Standing Waves
Physical Pendulum
When dealing with complicated systems, the mass moment of inertia is an important parameter, as it...
Sound as Pressure Waves
The pressure fluctuation depends on the difference in displacements between the successive points in the...


