Ascensión Island Volcano - John Seach


South Atlantic Ocean

 7.95 S, 14.37 W
summit elevation 859 m

Ascensión Island is located in South Atlantic, 80-100 km west of the median valley of the Mid-Atlantic Ridge. base covers approximately 2000 km 2 of the ocean floor about 3000 m below sea-level. The island contains 44 dormant craters, and covers an area of 98 sq km. The climate on Ascensión Island is subtropical.

The volcano erupted from a hot spot, presently located 225 km southeast of Ascension Island.

Ascension Island is a British Overseas Territory which, together with St Helena and Tristan da Cunha, forms a single territorial grouping. The island was discovered by the Portuguese sailor Joao da Nova Castelia in 1501.

Ascensión Island lies west of the Mid-Atlantic Ridge. Much of the island is covered by basalt lava flows and cinder cones, with 44 distinct craters visible.

Green mountain is the island summit. The island is home to Green Turtles, sooty tern, boobies, Ascension frigate birds, Boatswain birds, petrels and noddies.

Eruptions of Ascension Island
The youngest volcanic activity, vented principally hawaiite from areas to the north, northwest, and south of Sisters Peak. Lava flows in the Sisters Peak area erupted from several different locations at about the same time. Mapping shows that these events were controlled by northwest trending faults.

A second major young vent area is located on the southeast side of South Gannet Hill, near the Wideawake Airfield. This flow is approximately the same age as the flows in the Sisters Peak area. Petrologically the South Gannet Hill flow is quite similar to the flows around Sisters Peak.

Hummock Point is located on the northeast side of the island, and was the site of young eruptions. The eruption was controlled by a N-S trending fracture zone that projects into the Devil's Cauldron area.

An eruptive center is located at about 595 m elevation southeast of The
Peak on Green Mountain. This is the main vent of a volcano that formed lava flows and ash deposits covering the southeast of the island. Products of this
eruptive center include a hawaiite flow exposed in the wall of Cricket Valley, and a flow 1 km SW of Castle Hill.

Ascensión Island Volcano Eruptions

Eruptions about 600 years ago.