Abstract
Data from the GRSN and SPICED array are used to investigate lower mantle structure beneath the North Atlantic Ocean just south of Nova Scotia. We study S waves in an attempt to determine whether a D ′′ discontinuity can be observed in this region. The reflected phase SdS cannot be observed unambiguously, so we cross-correlate the traces with synthetic seismograms generated using a number of different 1D Earth models that incorporate positive and negative velocity discontinuities and gradients, as well as thin, high-velocity lamellae. The cross-correlation shows that a discontinuity with an S-wave velocity increase of magnitude 1–3% exists, which exhibits significant topography between 86 and 286 km above the CMB. The study area is located on the edge of a region of anomalously high seismic velocity identified by tomographic modelling, which fits with our observation of a high-velocity discontinuity.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
