![]() Products of thisĮruptive center include a hawaiite flow exposed in the wall of Cricket Valley, and a flow 1 km SW of Castle Hill. Ascension is one of the most interesting volcanic islands in the world, home to vast nesting turtle populations, migrating land crabs, large seabird colonies. This is the main vent of a volcano that formed lavaįlows and ash deposits covering the southeast of the island. Tristan da Cunha island, the largest and northernmost of the group, is roughly circular, with a coastline of 21 miles (34 km) and a central volcanic cone (6,760 feet 2,060 metres) that is usually cloud-covered. The eruption was controlled by a N-S trending fracture zone that projects into the Devil's Cauldron area.Īn eruptive center is located at about 595 m elevation southeast of The Hummock Point is located on the northeast side of the island, and was the site of young eruptions. ![]() Petrologically the South Gannet Hill flow is quite similar to the flows around Sisters Peak. This flow is approximately the same age as the flows in the Sisters Peak area. Mapping shows that these events were controlled by northwest trending faults.Ī second major young vent area is located on the southeast side of South Gannet Hill, near the Wideawake Airfield. Lava flows in the Sisters Peak area erupted from several different locations at about the same time. The youngest volcanic activity, vented principally hawaiite from areas to the north, northwest, and south of Sisters Peak. The island is home to Green Turtles, sooty tern, boobies, Ascension frigate birds, Boatswain birds, petrels and noddies. It is part of the British Overseas Territory of Saint Helena, Ascension and Tristan da Cunha, of which the main island is St Helena. The Ascension Island is named after the day of its recorded discovery, Ascension Day. Much of the island is covered by basalt lava flows and cinder cones, with 44 distinct craters visible. The nearest land is Saint Helena, 1,296 km (805 mi) to the south-east. The island was discovered by the Portuguese sailor Joao da Nova Castelia in 1501.Īscensión Island lies west of the Mid-Atlantic Ridge. The volcano erupted from a hot spot, presently located 225 km southeast of Ascension Island.Īscension Island is a British Overseas Territory which, together with St Helena and Tristan da Cunha, forms a single territorial grouping. The climate on Ascensión Island is subtropical. The island contains 44 dormant craters, and covers an area of 98 sq km. base covers approximately 2000 km 2 of the ocean floor about 3000 m below sea-level. Ascensión Island is located in South Atlantic, 80-100 km west of the median valley of the Mid-Atlantic Ridge.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |