Analytical modeling of gravity changes and crustal deformation at volcanoes: The Long Valley caldera, California, case study

摘要: Abstract Joint measurements of ground deformation and micro-gravity changes are an indispensable component for any volcano monitoring strategy. A number analytical mathematical models available in the literature that can be used to fit geodetic data infer source location, depth density. Bootstrap statistical methods allow estimations range inferred parameters. Although often assume crust is elastic, homogenous isotropic, they take into account different geometries, influence topography, gravity background noise. The careful use models, together with high quality sets, produce valuable insights nature deformation/gravity source. Here we present a review various modeling methods, historical unrest at Long Valley caldera (California) from 1982 1999 illustrate practical application bootstrap constrain unrest. key question whether since late 1970s explained without calling upon intrusion magma. answer, apparently, no. Our indicates inflation slightly tilted prolate ellipsoid (dip angle between 91° 105°) 6.5 7.9 km beneath resurgent dome aspect ratio 0.44 0.60, volume change 0.161 0.173 km 3 density 1241 2093 kg/m . larger uncertainty estimate reflects higher noise measurements. These results consistent silicic magma significant amount volatiles dome.