Geologic Background:
Huila, the highest active volcano in Colombia,
consists of an elongated N-S-trending volcanic chain
mantled by a glacier icecap. The volcano was constructed
within a 10-km-wide caldera. Volcanism at Huila has
produced six volcanic cones whose ages in general
migrated from south to north. Two glacier-free lava domes
lie at the southern end of the Huila volcanic complex.
The three main peaks are named Pico Norte, Pico Central
and Pico Sur. Pico Central is the highest summit in the
Cordillera Central, is composed of interbedded tephra and
steep-sided lava flows located inside an old caldera. The
volcano has 13.4 square kilometers of glacial cover.
Historic Activity:
- Huila's only known eruption was an explosion which
took place in 1555.
Recent Activity:
- Two persistent steam columns rise from the central
peak, and hot springs are also present.
- A regional earthquake (M 6.4 at 2.9°N,
76.2° W) caused a catastrophic release of
gravitationally unstable rock, snow, and ice down the
volcano's slopes resulting in mudflows on June 6, 1994.
Tremor pulses have been recorded since the
earthquake.
- Earthquake swarms in Feb and May 2000.
Data Sources
- Smithsonian's SEAN Bulletin (V. 8, No. 3 to V. 14,
No. 12)
- Global Volcanism Network (V. 15, No. 1 to V. 23, No.
2).
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