T11A-2867
New crustal thickness estimates of the Australian Continent using virtual deep seismic soundings
Monday, 14 December 2015
Poster Hall (Moscone South)
David A Thompson, University of Aberdeen, Aberdeen, United Kingdom, Nicholas Rawlinson, Australian National University, Canberra, Australia and Hrvoje Tkalcic, Australian National University, Canberra, ACT, Australia
Abstract:
Australia is a complex amalgamation of both Precambrian and Phanerozoic crustal terranes. Archean blocks in the west are separated by Proterozoic orogeny, and central Australia also exhibits accretion of a number of Proterozoic domains through EW-trending suture zones. A number of seismic initiatives have been instigated across the continent to better understand the detailed connection at depth between these contrasting geological regions. Here, we present new crustal thickness estimates using the virtual deep seismic sounding (VDSS) method for broadband station WRAB (Warramunga) and the NS-oriented BILBY network. The large data volume afforded by WRAB shows a high signal-to-noise ratio SsPmp phase across the 30°-50° epicentral distance range, along with other prominent direct and reverberated crustal phases. Crustal thickness estimated from the VDSS data are in the region of 43km, in good agreement with previous estimates. Results from the 25 station BILBY transect also see distinct crustal thickness variations between adjacent terranes.
