July 29, 2026 — Sulfur Cone gas monitoring maintenance, Mauna Loa
Detailed Description
This photograph shows the inside of the USGS Hawaiian Volcano Observatory (HVO) Multi-Gas site at Sulfur Cone high up on Mauna Loa's Southwest Rift Zone. Volcanic gas (Sulfur Dioxide, Hydrogen Sulfide, Carbon Dioxide, and Water vapor) concentrations are measured then telemetered back to HVO to be monitored and analyzed by HVO gas scientists. USGS photo by C. Sealing.
Sources/Usage
Public Domain.