Santa Ana

Thermal activity at the surface of a volcano is evidence of volcanic heat below. The fumarolic activity seen here produces vigorous steam plumes along the sulfur-encrusted wall of the summit crater at El Salvador's Santa Ana volcano. Thermal activity is common during non-eruptive periods at many volcanoes and may persist for many thousands of years. In addition to the fumarolic activity in this photo, the interaction of high-temperature volcanic fluids and gases with groundwater in hydrothermal fields can produce geysers, hot-spring pools, and mudpots.

Type/Process: Geothermal Activity
Volcanic Status: Historical
Image Number: 040-047
Photographer: Kristal Dorion, 1994 (U.S. Geological Survey)
Summit Elevation: 2381 meters
Latitude/Longitude: 13.853 N / 89.630 W
Timeframe: Last known eruption 1900-1963
Region: Mexico and Central America