New Google Earth data set: Galapagos "hotspot" dates: present & restored.
Ar/Ar and K/Ar dates from Galapagos "hotspot" region.
Two renderings: (1) Present day sample locations and (2) restored locations. (Vertical dimension: Age (Ma) multiplied by 5000 m.)
Restored locations: Rotated back to Hawaiian hotspot reference frame for inferred crystallization age. Hawaiian-Pacific model: Raymond et al. (2000, corrected). Relative plate reconstructions: Pilger (2007 compilation). Interpolated using splined pseudovectors (method of Pilger, 2003). For dates older than 9 Ma from Malpelo Ridge and offshore Panama east of 82 degrees W longitude, it was assumed that they formed on the Cocos plate and were transferred from the Cocos to the Nazca plate at 9 Ma.
Note that oldest dates from Cocos, Carnegie, and Malpelo Ridges cluster in a circle with diameter on the order of 500-600 km.
Sources: White et al (1993), O'Connor et al (2007).
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