Estudio del margen oriental de la Península Antártica aplicando deconvolución de Euler

Resumo

The Antarctic Peninsula, part of the Mesozoic-Cenozoic Andean orogenic belt, is composed of igneous and metamorphic rocks and separates from South America during the opening of the Drake Passage from the Oligocene. The eastern margin is poorly known due to its inaccessibility and is described as a continental passive margin gradually in transition to the Weddell Sea ocean floor. The modelling of 3 magnetic and gravimetric profiles (Rey-Moral et al., 2020) shows [1] that the eastern margin of the Antarctic Peninsula depicts a progressively thinning of the upper crust towards the SE, [2] changes in the sedi- ment thickness and [3] basaltic dikes related to the western edge of the Weddell Sea. Moreover, the 3D Euler deconvolution analysis, allowed estimating the anomaly source locations. Some well-focussed set of solutions has been determined by using structural index 1, to obtain results from vertical contacts and a 20x20 km window size to reach crustal structures. In: [1] the Antarctic Peninsula depth sources less than 10 km related to the Pacific Margin Anomaly batholiths and [2] the Bransfield Strait between 10 and 12 km depth discontinuities associated to intrusions. At the eastern Antarctic Peninsula margin, a group of solutions follows an outstanding N-S trend close to 55°W, probably related to the boundary where continental crust thins and the oceanic crust originates.