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Preliminary palaeomagnetic results from the Paleozoic volcanic units along the Gondwana margin in Argentina are presented. Even though we are still working on the palaeomagnetic data of the sampled section, these data are consistent with data from former studies carried out in the area. More than 90 specimens were measured from the Sierra Chica locality (37°52′S; 65°27′W) computed in 11 sites (Sc1-Sc11). These rocks are carriers of a characteristic remanence magnetization with reverse polarity, acquired during the Early Permian and assigned to the Kiaman Superchron. The resulting palaeomagnetic pole (PP) is Lat.: 64°S; Long.: 017°E, A95 = 15°, K = 12, N = 10. Others interpretations are also possible if the directions of two sites (SC9 and SC10) are considered to have a different magnetic field record, In that case, the PP calculated for sites Sc1-Sc7 is Lat.: 65°S; Long.: 44°E, A95 = 8°, K = 54, N = 7, and the virtual geomagnetic pole (VGP) calculated for sites Sc9 and Sc10 is Lat.: 48.5°S; Long.: 315°E, A95 = 8°, N = 2. The last possibility to consider Sc9 and Sc10 after structural correction, and the resulting PP position is Lat.: 66.5°S; Long.: 034°E, A95 = 8°, K = 41, N = 9. This deformation episode could be related to the San Rafaelic orogenic phase, found for the first time in La Pampa province, but previously observed in other neighboring areas during Permian time. However, more detailed palaeomagnetic sampling, rock magnetism studies, and age dating are necessary to complete the palaeomagnetic study of this area. Copyright © The Society of Geomagnetism and Earth, Planetary and Space Sciences (SGEPSS); The Seismological Society of Japan; The Volcanological Society of Japan; The Geodetic Society of Japan; The Japanese Society for Planetary Sciences; TERRAPUB.


Documento: Artículo
Título:New palaeomagnetic results from Late Paleozoic volcanic units along the western Gondwana margin in La Pampa, Argentina
Autor:Tomezzoli, R.N.; Saint Pierre, T.; Valenzuela, C.
Filiación:Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
Departamento de Ciencias Geológicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, 1428 Pabellón II, Ciudad Universita, Buenos Aires, Argentina
Palabras clave:Choiyoi volcanism; Gondwana; Late Paleozoic; Palaeomagnetism; South America; deformation; geomagnetism; Gondwana; magnetic field; magnetic reversal; paleomagnetism; Paleozoic; Permian; remanent magnetization; volcanism; Argentina; La Pampa; South America
Página de inicio:183
Página de fin:189
Título revista:Earth, Planets and Space
Título revista abreviado:Earth Planets Space


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---------- APA ----------
Tomezzoli, R.N., Saint Pierre, T. & Valenzuela, C. (2009) . New palaeomagnetic results from Late Paleozoic volcanic units along the western Gondwana margin in La Pampa, Argentina. Earth, Planets and Space, 61(1), 183-189.
---------- CHICAGO ----------
Tomezzoli, R.N., Saint Pierre, T., Valenzuela, C. "New palaeomagnetic results from Late Paleozoic volcanic units along the western Gondwana margin in La Pampa, Argentina" . Earth, Planets and Space 61, no. 1 (2009) : 183-189.
---------- MLA ----------
Tomezzoli, R.N., Saint Pierre, T., Valenzuela, C. "New palaeomagnetic results from Late Paleozoic volcanic units along the western Gondwana margin in La Pampa, Argentina" . Earth, Planets and Space, vol. 61, no. 1, 2009, pp. 183-189.
---------- VANCOUVER ----------
Tomezzoli, R.N., Saint Pierre, T., Valenzuela, C. New palaeomagnetic results from Late Paleozoic volcanic units along the western Gondwana margin in La Pampa, Argentina. Earth Planets Space. 2009;61(1):183-189.