Volcano Watch: Chemical analyses shed light on possible origins of island ash deposits

  • USGS photo by Z. Tamashiro USGS Hawaiian Volcano Observatory scientists examine an outcrop of reddish-brown Hilo ash during a recent study to investigate the origins of volcanic ash deposits on the Island of Hawaii. Age dates of lava flows above and below the Hilo ash deposit indicate that the ash was erupted between 3,000 and 14,000 years ago.

The origin(s) of volcanic ash deposits on the Island of Hawaii have been an enigma, especially those found on and between Kilauea and Mauna Loa. We know that ash is from explosive eruptions, but the question has been “from which volcano?”