Files
Abstract
Using Global Phase Seismic Interferometry (GloPSI) and methods originally formulated for active-source experiments, we develop a workflow for passive reflection profiling using PKIKP (range: 120 degrees -180 degrees) as a virtual seismic source. Instead of autocorrelation, we use estimates of the source-time function to deconvolve records for each earthquake prior to stacking. Array recordings for a given earthquake are windowed into overlapping subsets of traces and slant stacked to aid in the removal of PKP and PKiKP arrivals that interfere with PKIKP-generated reflections in the 140 degrees - 160 degrees range. This greatly expands the inventory of events that can be used to construct a subsurface image. Coherency-filtered slant stacks for each spatial window then are migrated and the partial images stacked to construct a migrated section. Tests with single earthquakes recorded by the Southeastern Suture of the Appalachian Margin Experiment (SESAME) array show coherent reflections from the Moho (depths: 30-40 km) and sub crustal lithosphere (80-100 km).