1.60 Ga felsic volcanic blocks in the moraines of the Terre Adélie Craton, Antarctica: Comparisons with the Gawler Range Volcanics, South Australia

Autor: J.J. Peucat, Christopher Fanning, L Testut, L Pecora, René-Pierre Ménot, R Capdevila
Rok vydání: 2002
Předmět:
Zdroj: Australian Journal of Earth Sciences. 49:831-845
ISSN: 1440-0952
0812-0099
DOI: 10.1046/j.1440-0952.2002.00956.x
Popis: Rhyodacite and rhyolite blocks found in numerous moraines on the Terre Adelie Craton in Antarctica are samples of a high-temperature high-K calc-alkaline to alkali-calcic igneous suite emplaced at ca 1.60 Ga. They comprise lavas and pyroclastic rocks, including ignimbritic varieties, chemically representative of anorogenic and post-orogenic igneous suites. The eruptive centres are probably close to the coast according to radar satellite images that show the trace of the ice streams. The volcanic suite is similar in age, petrography and chemical composition (major and trace elements as well as Nd isotopes) to the Gawler Range Volcanics from the Gawler Craton of South Australia. These similarities strengthen correlations previously established between the Gawler Craton and the Terre Adelie Craton (Mawson Continent). Moreover, the present petrological, geochemical and geochronological data give a new insight into the last major thermal event affecting the Mawson Continent. The results also highlight the useful contribution of moraines to our knowledge of Antarctic geology.
Databáze: OpenAIRE