Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6441104 | Lithos | 2011 | 18 Pages |
Abstract
⺠We report a migration of back-arc alkaline volcanism towards the north-northwest of 40 mm/yr., consistent with arc-parallel mantle flow models. ⺠In the opposite direction we report and age migration 35 mm/yr. in the adakites tracking the southwest migration of the triple junction where the Panama Fracture Zone intersects the Middle America Trench. ⺠The alkaline magmas are restricted to areas that have no seismic evidence of a subducting slab with a geochemistry controlled by mantle upwelling. ⺠Mantle potential temperatures (TP) of the alkaline basalt primary magmas increased from expected ambient mantle TP~ 1380-1410ËC in the Pliocene to TP's higher than ambient mantle (TP max = 1450ËC) in the younger units.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Geochemistry and Petrology
Authors
Esteban Gazel, Kaj Hoernle, Michael J. Carr, Claude Herzberg, Ian Saginor, Paul van den Bogaard, Folkmar Hauff, Mark Feigenson, Carl III,