Inversion modeling of multiple geophysical data sets for geothermal exploration: application to Roosevelt Hot Springs area. Final report

Abstract

Contours of observed g r a v i t y data i n t e r-Gravity data, low-pass f i l t e r e d w i t h a Gravity data, low-pass filtered, decimated Gravity data but zero-meaned and detrended Model g r i d , seismic staeions and earthquake Trade-off curves f o r travel-time inversion Contour map of velocity perturbations i n Layer 1 (0-1 km) of the f i n a l j o i n t Layer 2 (1-2 km) of j o i n t inversion model Layer 3 (2. 0-3. 5 km) of j o i n t inversion model f o r NDF = 7 4 .

Joint inversion of gravity and traveltime data using a level-set-based structural parameterization

“…Since density contrast generates gravity anomalies and slowness affects formation of seismic traveltimes, it is essential to establish relationship between these two different properties so that gravity data and traveltime data can complement each other in interpretations. An explicit approach, when applicable, is to specify a simple analytic formula between the values of density and slowness (Birch, 1961;Gardner et al, 1974;Savino et al, 1982;Nielsen and Jacobsen, 2000;Afnimar et al, 2002). For instance, Nielsen and Jacobsen (2000) apply a linear relation with S −1 = bρ + a and Afnimar et al (2002) derive a log-linear formula with ρ = a ln S + b, where ρ denotes density, S denotes slowness, and a and b are empirical parameters with different values in different formulas.…”