Recent hydrovolcanic deposits with evidence of magmatic immiscibility on Deception Island, Antarctica

• Language: unknown
• Published: 2004
• Subjects: Antarctica; Deception Island; Historical eruptions; Hydrovolcanism; immiscibility; magma; volcanic eruption; Arctic and Antarctic; South Shetland Islands; World; Antarctic; Arctic; Argentina; Antarc*
• Online Access: https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00044822_v59_n3_p495_Caselli; https://hdl.handle.net/20.500.12110/paper_00044822_v59_n3_p495_Caselli

Outcrops of hydro-volcanic deposits on Deception Island are stratigraphically re-classified. The sequence was assigned to a pre-caldera phase, but it has very different compositional and consolidation characteristics, enabling it to be differentiated and redefined as a new unit. In this paper, it is stratigraphically relocated as a historical eruption, on the basis of its compositional similarity to ash-falls in Bransfield Basin. The studied deposits are bimodal (basaltic/rhyolitic) implying a relationship with magma immiscibility. The occurrence of more acidic periods would allow relatively more explosive vents with greater particle dispersion to take place. © 2004 Asociación Geológica Argentina.