The IGUANA Project

Imaging Galapagos Upwelling and Neotectonics of the Archipelago



  • University of Oregon
  • Carnegie Institution of Washington
  • Instituto Geofisico, Escuela Politecnica Nacional, Quito, Ecuardo


Villagómez, D. R., D. R. Toomey, E. E. E. Hooft, and S. C. Solomon (2007), Upper mantle structure beneath the Galápagos Archipelago from surface wave tomography, J. Geophys. Res., 112, B07303, doi:10.1029/2006JB004672.

Fontaine, F. R., E. E. E. Hooft, P. G. Burkett, D. R. Toomey, S. C. Solomon, P. G. Silver, Shear-wave splitting beneath the Galápagos archipelago, Geophys. Res. Lett., 32, L21308, doi:10.1029/2005GL024014, 2005.

Hooft, E. E. E., D. R. Toomey and S. C. Solomon, Anomalously Thin Transition Zone Beneath the Galápagos Hotspot, Earth and Planet. Sci. Lett., 216, 55-64, 2003.

Project Summary

Topographic map of the Galapagos Archipelago and the Galapagos Spreading Center
(generated by Bill Chadwick, OSU)

The Galápagos hotspot and Galápagos Spreading Center system is a particularly promising environment for developing a comprehensive model of hotspot magmatism and the dynamics of hotspot-ridge interactions. There have been a wide range of studies at the Galápagos, including geochemical and petrological work, geophysical analyses, and experimental and numerical modeling.  Despite these efforts, the pattern of mantle upwelling and the form of interaction between the Galápagos hotspot and the nearby Galápagos Spreading Center system remain largely unknown.  Outstanding questions are:

  • Is the Galápagos hotspot associated with a plume-like feature in the upper mantle?
  • Where is the center of the Galápagos hotspot/plume located?
  • What are the approximate lateral dimensions of the hotspot/plume?
  • How does the hotspot interact with oceanic lithosphere?

To address these questions, the University of Oregon, the Carnegie Institution of Washington, and the Instituto Geofisico, Escuela Politecnica Nacional, Quito, Ecuador conducted a multi-year passive seismic experiment at the Galápagos Islands. Our experiment, designed to be a reconnaissance study of the region, recorded high-quality three-component broadband seismic data. We are currently analyzing the data for crustal and upper mantle structure.

Volcanic Galapagos

Enter Volcanic Galapagos: A web site of background information about the Galapagos Islands and photos from our field work

Crustal Imaging

Upper Mantle Imaging

Scientific Personnel


Toomey's Site

DEPARTMENT OF Geological Sciences, University of Oregon