Physics‐Based Model Reconciles Caldera Collapse Induced Static and Dynamic Ground Motion: Application to Kīlauea 2018

Inflationary deformation and very long period (VLP) earthquakes frequently accompany basaltic caldera collapses, yet current interpretations do not reflect physically consistent mechanisms. We present a lumped parameter model accounting for block/magma momentum change, magma chamber pressurization, ring fault (assumed vertical) shear stress drop. Pressurization of the underlying is represented by tri-axial expansion source, combined change vertical single force. The applied to Kīlauea 2018 collapse events, accurately predicting near field static/dynamic ground motions. In addition force contributes significantly VLP waveforms. For an average event with fully developed fault, Bayesian inversion constrains drop ∼0.4 MPa pressure increase ∼1.9 MPa. That predictions fit both geodetic seismic observations confirms that captures dominant