Global Volcanism Program | Image GVP-05830
The flat, grooved surface of this lava block was sandblasted by high-velocity pyroclastic surges during an eruption in 1775. The pyroclastic surges accompanied formation of the 700-m-wide Tolire Jaha maar on the NW flank of Gamalama.
Photo by Jack Lockwood, 1980 (U.S. Geological Survey).
This image is made available under the Creative Commons BY-NC 4.0 license terms.