Eastern Indonesia is one of the least well-understood geological domains of our planet, and yet the region provides a truly remarkable location for unraveling some of the major puzzles of plate tectonics. The recent collision of the Australian continent with the active volcanic arc in the Banda region effectively captures the initiation of continental mountain building and the cessation of island arc volcanism, offering a rare glimpse into a set of processes that have shaped Earth’s evolution over geologic time.  Since oceanic subduction and subsequent continental collision have occurred in different stages along the Banda arc, we plan to use the region to study and assess the spatio-temporal evolution of this transition using a variety of methods: seismology, geodyanmics, tectonics, low-temperature geochemistry, and geomorphology.  We have installed 30 broadband seismometers, including the first ever seismometer on Timor Leste, across the archipelago of eastern Indonesia (NTT) in 2014.   The award is co-funded by the NSF Geophysics and Tectonics Programs, and the Office of International Science and Engineering (OISE) – Global Venture Fund (GVF).

This project is led by myself in collaboration with Profs. Becker and West at USC.

For more details about the broadband seismology experiment check out our blog!  bandaarc.blogspot.com

banda_topo_stns_eq_volcs_mar15

Red triangles are broadband seismometers deployed in Timor-Leste and white triangles are stations deployed in Indonesia.  The colored dots represent earthquake hypocenters (Das, 2002).

Initial Results:

Porritt, R.W., Miller, M.S., O’Driscoll, L.J.,Harris, C.W., Roosmawati, N., and Teofilo de Costa, L.  (2016), Continent–arc collision in the Banda Arc imaged by ambient noise tomography, Earth and Planetary Science Letters, 449, 246-258, doi:10.1016/j.epsl.2016.06.011.

Miller, M.S., O’Driscoll, L.J., Roosmawati, N., Harris, C.W., *Porritt, R.W., Teofilo de Costa, L., Soares, E., Widiyantoro, S., Becker, T.W., and West, A.J. (2016), The Banda Arc experiment: Transitions in the Banda Arc – Australian continent collision, Seismological Research Letters, in press.