2025 Annual Campaign GPS measurements in progress
Detailed Description
A benchmark on the northwest side of Mauna Loa's summit being surveyed by GPS campaign instruments. The metal disk on the ground beneath the tripod is the benchmark, which is cemented to the lava flow surface so that the specific spot can be measured each year. Mauna Kea is visible in the background. USGS photo by A. Ellis.
Sources/Usage
Public Domain.