Isla Isabella, Galapagos Island
Click on image for larger annotated version
This image of the Galapagos Islands captures two large shield volcanoes on Isla Isabella, the largest and least inhabited island in the Galapagos chain. The northern volcano is Darwin and the southern, Alcedo. Isla Fernandina and Isla San Salvador are just visible on either side of Isla Isabella.
The western Galapagos Islands, which lie about 750 miles west of Ecuador in the eastern Pacific, have six active volcanoes similar to the volcanoes found in Hawaii. These are shield volcanoes shaped like flattened dome, broad and low, built by flows of very fluid lava. These volcanoes reflect the volcanic processes that occur when the ocean floor is created. The islands are largely desolate lava piles with little vegetation along the coastlines. However, the high volcanic mountains generate rains that have mantled the summits with dense jungle. The islands are famous not only for their volcanic associations but also for the peculiar flora and fauna that result from isolation from any continental mainland.
Since the time of Charles Darwin's visit to the area in1835, there have been over 60 recorded eruptions on these volcanoes. Unlike Hawaii, these volcanoes are infrequently studied due to their inaccessibility and delicate ecology. In addition, the rugged terrain and lack of water and field support make these volcanoes difficult to map and study. A major eruption on Fernandina Island in 1974 went unnoticed on the ground until observed by astronauts aboard the Skylab 4.
This image was taken from the Space Shuttle on February 17, 2000. <!--Image, geographic, and position and camera information can be viewed on the ISS EarthKAM meta data page.-->