A large porphyritic dyke exposed at Porphyry Ridge, Paradise Harbour, Danco Coast (northern Antarctic Peninsula, West Antarctica), consists of albitized andesite. Together with other hypabyssal intrusions (dyke swarm) and plutonic intrusions (granite-granodiorite-gabbro - mainly sills), it belongs to the Late Cretaceous Andean Intrusive Suite (AIS) which post-dates a monotonous, some 2000 m thick, Early Cretaceous basaltic-andesitic volcanic pile (Antarctic Peninsula Volcanic Group - APVG). The volcanic effusions (APVG) and the successive plutonic and hypabyssal intrusions (AIS) had formed in response to subduction of the SE Pacific oceanic crust under continental crust of Antarctic Peninsula.
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