Evidence for petit-spot volcanism in the Puerto Rico Trench

Nicholas Harmon; William W. Danforth; Uri S. ten Brink; J. Pablo Canales; Shuoshuo Han; Elizabeth Vanacore; Jose-Luis Granja-Bruna; Wayne E. Baldwin; Seth D. Ackerman; Liam Moser; Elisaveta Sokolkova

doi:10.1029/2024gl114362

USGS · 70271336

Evidence for petit-spot volcanism in the Puerto Rico Trench

Nicholas Harmon·William W. Danforth·Uri S. ten Brink·J. Pablo Canales·Shuoshuo Han·Elizabeth Vanacore·Jose-Luis Granja-Bruna·Wayne E. Baldwin·Seth D. Ackerman·Liam Moser·Elisaveta Sokolkova

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Abstract

Petit-spot volcanism occurs in intraplate settings along the outer rise of subducting plates. Here we present evidence for petit-spot type of volcanism from multibeam bathymetry and backscatter data from the Puerto Rico Trench (PRT). It is the first report of such volcanism in the Atlantic basin. Up to 34 possible petit-spot volcanic cones are mapped in the eastern section of the PRT, with an average diameter of 950 m and a mean height of 92 m. The seamounts are in a region of the PRT that has the longest and highest bending faults, up to 50.6 km long and 1.49 km high. Some of the volcanic cones are associated with fault scarps. The larger bending fault scarps in the region of the volcanic cones suggest the stress state in the eastern PRT is favorable for allowing asthenospheric melt to escape to the surface.

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Geophysical Research Letters Article

Source-reported bounding extent: 18.36287066782539° to 19.249247418941295° latitude; -67.21055429066269° to -65.10592830934482° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Nicholas Harmon, William W. Danforth, Uri S. ten Brink, J. Pablo Canales, Shuoshuo Han, Elizabeth Vanacore, Jose-Luis Granja-Bruna, Wayne E. Baldwin, Seth D. Ackerman, Liam Moser, Elisaveta Sokolkova. 2025-05-26. Evidence for petit-spot volcanism in the Puerto Rico Trench. https://doi.org/10.1029/2024gl114362

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