Ascension Island, located just west of the Mid-Atlantic Ridge, was discovered on Ascension Day in 1501 by the Portuguese navigator Joao da Nova. It is the broad emergent summit of a massive stratovolcano that rises 3,000 m above the sea floor. The isolated island has more than 100 youthful cones and lava domes, many aligned along two fissures. Basaltic rocks dominate on the island, but trachytic lava domes are also present, mostly on the eastern side. Although no eruptive activity has occurred since its discovery, many volcanic features have a very youthful appearance. Two of the youngest lava flows were erupted from flank vents and reached the sea on the N and S coasts. Argon-Argon dating by Preece and others (2018) identified three eruptions within the past 2,000 years.
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The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography.
Bell J D, Atkins F B, Baker P E, Smith D G W, 1972. Notes on the petrology and age of Ascension Island, south Atlantic (abs).
Eos, Trans Amer Geophys Union
, 53: 168.
Daly, Reginald A., 1925. The Geology of Ascension Island.
Proceedings of the American Academy of Arts and Sciences
, 60: 3-80.
Harris C, 1983. The petrology of lavas and associated plutonic inclusions of Ascension Island.
J Petr
, 24: 424-470.
IAVCEI, 1973-80. Post-Miocene Volcanoes of the World.
IAVCEI Data Sheets, Rome: Internatl Assoc Volc Chemistry Earth's Interior
.
Mitchell-Thome R C, 1970.
Geology of the South Atlantic islands
. Berlin: Gebruder Borntraeger, 350 p.
Preece K, Mark D F, Barclay J, Cohen B E, Chamberlain K J, Jowitt C, Vye-Brown C, Brown R J, Hamilton S, 2018. Bridging the gap: 40Ar/39Ar dating of volcanic eruptions from the 'Age of Discovery'.
Geology
, v. 46, p. 1035-1038.
https://doi.org/10.1130/G45415.1
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