Geological Research During 22-th Ukrainian Antarctic Expedition, February – April 2017: Argentine Islands of the Wilhelm Archipelago, Graham Coast

Summary In 2017, the authors began large-scale geological survey on the Argentine Islands where the Ukrainian research station is located. It was found that various manifestations of the Antarctic Peninsula arc magmatism are exposed on the Argentine Islands. They include volcanic, subvolcanic, hypabyssal and plutonic rocks. Most of the exposed area is composed by metamorphosed volcanic strata. Its pyroclastic rocks and andesite lavas are correlated with Antarctic Peninsula Volcanic Group. Their age is preliminary determined in the time interval from Jurassic to Cretaceous but it needs clarification. Additional study is also needed for silllike microdiorite intrusions in the volcanites. The extended outcrops of the Paleocene granitoids on the west of the Argentine Islands are the flank of a larger pluton. The latter is a part of Antarctic Peninsula Batholith and its youngest representative. Small mafic and intermediate dykes are represented by at least two age groups. Numerous Mesozoic dykes intrude exclusively volcanic strata. Less numerous Cenozoic dykes intrude both volcanites and Paleocene granitoids. Modern glacial and coastal marine sediments are slightly distributed on the exposed part of the islands. Some eratic boulders and glacial striations are evidences of a more ancient glaciation and they are deserved close attention.