Signatur:
ZSP-164-27
In:
The Geology of the South Shetland Islands
Beschreibung / Inhaltsverzeichnis:
Decption Island is a caldera formed by the subsidence of a group of overlapping volcanoes along arcuate and radial faults. Three volcanic episodes occured after the formation of the caldera and the location of those post-caldera volcanoes is controlled by the fault pattern which limits the caldera. Although it is possible to establish the relative ages of the four volcanic episodes, there is little information as to their absolute ages. It is probable that the latest eruptions occurred in historic times. Petrographically the Deception Island suite is a local alkaline deviation from the normal andesite-rhyolite association of the South Shetland Islands. Its lavas are characterized by an unusually high soda content. The sequence of crystallization is analogous to that of melts of certain composition in the system MgO-FeO-SiO2 crystallizing under conditions of strong fractionation. The geochemistry of the Deception Island volcanic rocks is reviewed and four new chemical analyses are presented.
Materialart:
Schriftenreihen ausleihbar
Seiten:
43 S. : Ill., graph. Darst., Kt. + 2 Kt.-Beil.
Serie:
27
URL:
http://www.antarctica.ac.uk/about_bas/publications/scientific_reports/index.php
Zweigbibliothek:
AWI Bibliothek
