Is the Isabella anomaly a fossil slab or the foundered lithospheric root of the Sierra Nevada batholith?

Charles R. Hoots1, Brandon Schmandt2, Robert W Clayton3, Steven M Hansen1 and Sara L Dougherty4, (1)University of New Mexico Main Campus, Albuquerque, NM, United States, (2)Rice University, Earth, Environmental, and Planetary Sciences, Houston, TX, United States, (3)California Institute of Technology, Seismological Laboratory, Pasadena, United States, (4)California Institute of Technology, Pasadena, CA, United States