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Geological position and age of Argentine Islands mafic dykes, West Antarctica
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, 17th International Conference on Geoinformatics - Theoretical and Applied Aspects, May 2018, Volume 2018, p.1 - 4
Abstract
Based on the recent field geological research combined with previous isotopic datings, it is shown that numerous mafic dykes, occuring among the Mesozoic-Cenozoic igneous rocks of the Argentine Islands and the adjacent territory, are formed during at least two stages. The Mesozoic stage of dykes formation is represented by the Cretaceous dykes of porphyritic microgabbros and microdiorites, which intrude the orogenic formations of the UJVG. Although, it is impossible to exclude the presence of even more ancient dykes genetically associated with UJVG. The Cenozoic stage, apparently, includes the dykes of several age groups. Among them, a significant place is occupied by the youngest dykes, which intrude the Cretaceous-Paleogene granitoids massifs after their final exhumation. The presence of such dykes indicates that magmatic activity in the region did not ceased in the Neogene, and possibly in the Quaternary. The subvolcanic features of these dykes allows to raise the question of finding coeval volcanic formations with the same age.