Seismological Analysis of the Mohorovičić and Mantle Discontinuities Below Cape Verde using Receiver Functions

Abstract

The Cape Verde Islands are a volcanically active archipelago with a long history of magmatic activity originating from a mantle plume. Current understanding of the depth origin of the Cape Verde Islands hotspot is limited and the exact seismic properties of the Mohorovičić discontinuity (Moho) and the mantle transition zone (MTZ) thickness are disputed. Until recently, there have been few seismometers on the islands in order to compile earthquake event data and few studies have used permanent station data. Using 18 years of data from station SACV and a supplementary year of data from station SVMA, we seek to better understand the crustal structure and MTZ below the Cape Verde archipelago with P-to-S receiver functions. It was discovered that the crust is at approximately 15-17 km thickness below stations SACV and SVMA, which matches up with the approximated thickness from LITHO1.0 data. The Moho is shallower due to Cape Verde being largely formed by thinner oceanic crust. Both the 410 km and 660 km discontinuities are deeper than average, implying a warmer than ambient conditions MTZ below Cape Verde.