Global Volcanism Program | Image GVP-00997
The unconsolidated pyroclastic flow and ash deposits emplaced during the June 1991 eruption of Pinatubo were remobilized by rain water as lahars for years after activity ceased. This photo shows erosion patterns in the deposits along the Maraunot River valley NW of Pinatubo on 27 November 1991.
Photo by Chris Newhall, 1991 (U.S. Geological Survey).
This image is made available as a Public Domain Work, but proper attribution is appreciated.