This side-viewing sonar image shows two 45 x 90 m craters on the NW flank of Don Joao de Castro Bank in the Azores taken by U.S. Navy submarine NR-1. The younger left crater displays a floor consisting of a chilled lava lake with polygonal surface fractures. The right crater is much less distinct because its surface is obscured by tephra deposits. The line at the right is the center track line of the sonar image.

U. S. Navy image courtesy of Rick Wunderman, 2003 (Smithsonian Institution).

This image is made available under the Public Domain Dedication CC0 license, but proper attribution is appreciated.

Keywords: remote sensing | submarine volcano

Don Joao de Castro Bank