DI11B-2591
Migration, Storage and Seismic Signatures of Melting at the Lithosphere-Asthenosphere Boundary
Monday, 14 December 2015
Poster Hall (Moscone South)
Zhengyu Cai1, Saswata Hier-Majumder2, Howard Elman2, Michael Stevens3, Nicholas C Schmerr1 and Vedran Lekic1, (1)University of Maryland College Park, College Park, MD, United States, (2)University of Maryland, College Park, MD, United States, (3)Royal Holloway University of London, Egham, TW20, United Kingdom
Abstract:
In this work we investigate the role of past and current episodes of partial melting at the Lithosphere-Asthenosphere Boundary (LAB) by combining geodynamic models of two-phase magma flow with a rock physics-based toolbox MuMaP (Multiphase Material Properties). The two-phase magma/mantle, time-dependent flow is modeled by conservational laws of fluid and solid matrix. Resulting coupled Stokes equations and Darcy's law are solved using finite-element method for a geologically relevant time, thus predicts the melt evolution within the upper mantle in terms of porosity distribution in 3-D space. Then we implement MuMap to forward calculate and visualize the seismic velocities of the two-phase mixture, resulting from variations in temperature, bulk composition and melt/frozen-in melt distribution. By exploring a broad parameter space, our work provides a framework to model and identify the most likely causes of the seismic anomalies at LAB and within the Lithosphere.
