The main goal of the ELSAF project is to image the crust and upper mantle surrounding the Cholame-Parkfield segment of the SAF between the Pacific coast and the Great Valley in Central California, including the source region of non-volcaninc Tremors (NVT) recently observed near Cholame (Nadeau and Dolenc, 2005). Along-strike variations of the conductivity structure between the source region of the NVTs near Cholame and the SAFOD near Parkfield may be directly related to the transition zone between the locked and the creeping segments of the SAF. ELSAF continues our previous efforts in Central California in the scope of the projects DeepRoot and TremorMT.