The Cayambe volcano, 70 kilometers northeast of Quito, is showing a slight but steady increase in seismic activity in recent weeks. A favorite with mountain climbers, the 5,800 meter (19,000 ft.) mountain has been dormant for 230 years.
Ecuador’s Geophysical Institute said it has been monitoring Cayambe closely since September when the recent increase of activity was first noted. Earthquakes of 3.3 and 3.6 magnitude under the mountain were recorded in November and geologists say the mountain is experiencing an internal “fracturing of rock that deserves close attention.”
The institute says that the new activity could eventually lead to an eruption but said it is too early to know the danger threat.
Although a number of mountain climbing websites list Cayambe is extinct, the institute says that this is not the case and that the volcano is “very much alive.” There was a large eruption in 1785 – 1786 but recent studies show the volcano has shown frequent eruptive activity over the past 4,000 years and appears to be on a 200-year eruptive cycle.
Cayambe has two lava domes near the summit, about 1.5 km apart. Several other lava domes are located on the upper flanks and have been the source of pyroclastic flows down the lower volcano flanks in the past.
The volcano, which is notable for being the only place on earth where the equator passes through a glacier, is 15 miles to the west of the town of Cayambe, population 15,000.