Evolución desde el Mioceno del margen pacífico de la Península Antártica frente a la Isla Adelaida: un ejemplo de margen pasivo glacialun ejemplo de margen pasivo glacial

Resumen

The analysis of the morphology and stratigraphy of the Antarctic Peninsula Pacific margin offshore from Adelaide Island shows 3 main evolutionary intervals, from the Late Miocene to the recent which clearly represent the growth phase of the margin under glacial influence. The oldest, transitional stage (SU4, Late Miocene-Early Pliocene), represents the first progradational unit over the shelf and slope, above the Base of the Glacial Margin Sequences. This unit contains drift facies on the rise and it represents an important change in the depositional style. The middle, progradational glacially-influenced margin stage contains two units (SU 3 & 2, Early to Late Pliocene) SU3 is composed of 3 progradational wedges (a, b & c) although the youngest one (a) is the thickest and represents the most important progradational stage of the margin. SU2 includes both progradational and aggradational deposits and it recorded a significant change in the margin growth pattern. The youngest aggradational glacially-influenced margin interval (SU I, Quaternary), recorded the last change in the depositional style of the margin, with a relatively thick upward and outward sediment wedge