J.P. Ormazabal

Lago Yehuin, a WNW-ESE elongated basin located in the outer fold-and-thrust belt of the Fuegian Andes, occupies a compartmented structural depression originated along a segment of the left-lateral Lago Deseado fault system. This paper describes the first geophysical survey performed within the lake. New acquired high-resolution single-channel seismic data, integrated with geological information in the surroundings of the Lago Yehuin, allowed to: (i) produce a complete bathymetric map of the lake, (ii) reconstruct the basement surface of the lake, and (iii) analyze the geometry, distribution, and thickness of the sedimentary infill. Two sub-basins were recognized within Lago Yehuin: A western sub-basin, 7.5 km long, with a maximum depth of 118 m; an eastern sub-basin, 7.2 km long with a maximum depth of 80 m. Both sub-basins are limited by a set of normal faults which overprint NE-verging thrusts. Three seismo-stratigraphic units have been identified in the seismic records: (1) a lower unit with wedged geometry interpreted as a mass flow deposits; (2) a thick (up to 120 m) intermediate unit of glacio-lacustrine nature and irregularly distributed in the Yehuin basin; (3) a thin (generally

Geophysical survey

Basement

Tierra

10.5027/andgeov45n3-3085

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Citations (16)

Structure of the wedge-top and foredeep of the Magallanes-Malvinas basins between 62° W and 67° W (SW Atlantic Ocean)

Journal of South American Earth Sciences (2019)

J.P. Ormazabal Alejandro Tassone Federico Esteban J.I. Isola Lubín Eric Cayo

Wedge (geometry)

10.1016/j.jsames.2019.04.016

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Citations (7)

Geomorphology and sedimentary processes on the Sloggett Canyon, Northwestern Scotia Sea, Argentina

Journal of South American Earth Sciences (2020)

F. Palma Graziella Bozzano S. Principi J.I. Isola J.P. Ormazabal

Submarine canyon

Continental Margin

Contourite

Mass wasting

10.1016/j.jsames.2020.103136

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Citations (9)

Neotectonics on the Namuncurá (Burdwood) Bank: unveiling seafloor strike-slip processes along the North Scotia Ridge

Journal of the Geological Society (2024)

J.P. Ormazabal S. Principi F. Palma Donaldo M. Bran J.I. Isola

The North Scotia Ridge is the offshore morphostructural expression of the left-lateral transcurrent South America–Scotia plate boundary. Several blocks make up the ridge, including the scarcely studied Namuncurá Bank (also known as the Burdwood Bank). We present the first detailed study of active structures on the seafloor of the western Namuncurá Bank from a database of 3D and 2D seismic data, multibeam bathymetry and sub-bottom profiles. This work assesses the architecture, style of deformation and Cenozoic evolution of Namuncurá Bank, where several groups of faults and en echelon folding affect the seabed and shallow sub-bottom. These features compound the northernmost structures associated with a releasing bend, fitting well with a left-lateral Riedel shear model oriented at N74°E, slightly rotated with respect to the present day plate boundary stress regime. The current tectonic scenario started with a main deformational phase in the Neogene, partially distributed by the Malvinas fold–thrust belt, while modern deformation continues to be conditioned by pre-existing structures. This study allows a better understanding of the tectonics of the North Scotia Ridge, a morphostructure that influences the circulation of the Antarctic Circumpolar Current, thus impacting the global climate.

Seafloor Spreading

Neogene

10.1144/jgs2023-215

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Citations (1)

Echo-characterization of the Sloggett Canyon and the interfluve with Valentín Canyon, Tierra del Fuego Continental Margin, Argentina

Deep Sea Research Part I Oceanographic Research Papers (2024)

F. Palma S. Principi J.P. Ormazabal Luana Acosta J.I. Isola

Tierra

Echo (communications protocol)

Continental Margin

Margin (machine learning)