May 29, 2025 — Kīlauea summit fieldwork after episode 23

A USGS Hawaiian Volcano Observatory geologist collects high-precision ground positions using a kinematic GPS instrument that measures its vertical and horizontal position. Once processed, these measurements will help scientists determine the thickness of the tephra deposit downwind of the ongoing Halema‘uma‘u eruption at Kīlauea summit. The tephra has primarily been falling in a closed area of Hawai‘i Volcanoes National Park, an area that HVO scientists access with permission from, and in coordination with, the National Park Service. USGS photo taken on May 29, 2025, by L. DeSmither.