Abstract
The dominant geomorphological unit of the Northern Patagonian Massif landscape is a regional planation surface, eroded across the crystalline basement (plutonic and metamorphic rocks), eruptive rocks of the Gondwana cycle (Early to Middle Carboniferous), and Jurassic volcanic rocks.
The most important active climate during the genesis of this surface had a very significant role, developing intense chemical weathering extending to variable depths with the corresponding degradation of the rocky material exposed at the surface. Remnants of the weathering profiles, both outcropping and fossilized by burial, are identified and described. Such a particular mega-landform was developed in a cratonic environment, mainly as a product of deep weathering, and it is interpreted as a denuded surface, an etchplain formed by corrosion followed by erosion.
The analysis of the relationships between relief, saprolite, and rock cover throughout time suggests that the most important factor for the classification of the present landscape is the duration of exposure of the crystalline basement at the surface, from the end of the Paleozoic and during the entire Mesozoic. This conclusion has essential relevance for the evaluation of the effects of Mesozoic tectonics and the powerful weathering under certain climatic conditions.
It is estimated that this paleosurface would have initiated its development towards the end of the Paleozoic, but later modifying also the Jurassic volcanic rocks that preceded the rifting processes that lead to the opening of the Southern Atlantic Ocean. Finally, the tectonic activity during the early Tertiary produced the exhumation of the planation surface, which was buried by its own regolith, reactivating erosion surfaces and small drainage basins. However, it is possible that some areas of the planation surface had never been covered by other rocks, other than its own overlying weathering products.
Our results suggest that the landscape features should not be assigned to Quaternary morphogenesis, but instead, they have evolved over a very long time, perhaps 100 Ma or even more. These observations refer to Mesozoic times, and therefore the time scale used for the discussion of the geomorphology of the Northern Patagonian Massif should be enlarged to properly analyze the evolution of the ancient landscapes of this cratonic region.
This chapter contributes to the analysis of comparative studies of global geomorphology of cratonic areas, where planation surfaces record very long periods in which the speed of crustal deformation is highly compensated by planation processes.
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References
Aguilera EY (2006a) Identificación y distribución de distintas superficies geomorfológicas de escaso relieve local, por medio de sensores remotos en el área del Macizo Nordpatagónico, Provincia de Río Negro. Unpublished doctoral Thesis, Facultad de Ciencias Naturales y Museo de La Plata, Universidad Nacional de La Plata, Argentina, 285 pp
Aguilera EY (2006b) Superficie de planación Gondwánica en el Macizo Nordpatagónico. III Congreso Argentino de Cuaternario y Geomorfología, Abstracts, Córdoba, Argentina
Aguilera EY (2007) Teledetección y SIG aplicados a la regionalización geomorfológica en el Macizo Nordpatagónico. In: SIMPÓSIO BRASILEIRO DE SENSORIAMENTO REMOTO, 13, (SBSR), 2007, Florianópolis. Anais. São José dos Campos, INPE, pp 1935–1942. CD-ROM, On-line. ISBN 978-85-17-00031-7
Aguilera EY, Rabassa J (2010) Origin of the Northern Patagonian Massif regional paleosurface. Geociências 29(4):467–478. São Paulo, UNESP
Aguilera EY, Aragón E, Carretero S (2010) The paleosurface on the Paso del Sapo volcanic rocks, Chubut, Argentina. Geociências 29:479–486. São Paulo, UNESP, Brazil
Aragón E, Carroll AR, Aguilera EY, Cavarozzi CE (2005) Ancient Gondwana landforms in Patagonia. Gondwana, 12, “Geological and Biological Heritage of Gondwana” Abstracts, Academia Nacional de Ciencias, Mendoza, p 46
Arrondo OG, Artabe AE, Morel EM, Petriella B (1984) Floras fósiles Mesozoicas. IX Congreso Geológico Argentino (San Carlos de Bariloche). Relatorio 2(1):367–372
Cicciarelli MI (1989) Análisis estructural del sector oriental del Macizo Nordpatagónico y su significado metalogénico. Unpublished doctoral thesis, Facultad de Ciencias Naturales y Museo de La Plata, Universidad Nacional de La Plata, Argentina, 179 pp
Derrau M (1970) Geomorfología. Editorial Ariel, Barcelona, 442 pp
Giacosa R, Lema H, Bosteros A, Zubia M, Cucchi R, Di Tomasso (2007) Estructura del Triásico de la región norte del Macizo Nordpatagónico (40°–41°S, 67°30′–69°45′O), Río Negro. Revista Asociación Geológica Argentina [online] 62(3):355–365. ISSN 1851–8249
Groeber PF (1929) Líneas fundamentales de la geología del Neuquén, Dir. Gral. Minas, Geol., Hidrol., Buenos Aires, Publ. 58. Min. de agric. de la Nación, Buenos Aires
Hinojosa LF, Villagrán C (2005) Did South American Mixed Paleofloras evolve under thermal equability or in the absence of an effective Andean barrier during the Cenozoic? Palaeogeogr Palaeoclimatol Palaeoecol 217(1–2):1–23
Kay SM, Ardolino A, Franchi M, Ramos V (1993) Origen de la Meseta de Somún Cura: distribución y geoquímica de sus rocas volcánicas máficas. 12º Congreso Geológico Argentino and 2º Congreso de Exploración de Hidrocarburos, Actas, 4, pp 236–248
Llambías EJ (2001) Geología de los Cuerpos Ígneos. In: Serie de Correlación Geológica 15, Instituto Superior de Correlación Geológica, INSUGEO, San Miguel de Tucumán, 232 pp
Llambías EJ, Rapela CW (1984) Geología de los complejos eruptivos de La Esperanza, provincia de Río Negro. Revista de la Asociación Geológica Argentina 39(3–4):220–243
Ollier C (1984) Weathering, 2nd edn. Longman, Essex
Ollier CD (1991) Ancient landforms. Belhaven, London
Pothe de Baldis ED (1984) Microfloras fósiles Mesozoicas. 9° Congreso Geológico Argentino (San Carlos de Bariloche). Relatorio 2(4):393–411
Rabassa J (1974) Geología superficial en la región de Pilcaniyeu-Comallo, provincia de Río Negro. Unpublished doctoral thesis, Universidad Nacional de La Plata
Rabassa J (1975) Geología de la región de Pilcaniyeu-Comallo, provincia de Río Negro, Argentina. Fundación Bariloche, Publicaciones del Departamento de Recursos Naturales y Energía, N° 17, San Carlos de Bariloche
Rabassa J (1978a) Paleorrelieves cenozoicos en la región de Pilcaniyeu-Comallo, provincia de Río Negro, Argentina. Actas 7° Congreso Geológico Argentino, Neuquén, pp 77–87
Rabassa J (1978b) Estratigrafía de la región de Pilcaniyeu-Comallo, provincia de Río Negro, Argentina. Actas 7° Congreso Geológico Argentino, Neuquén
Rabassa J, Carignano C, Cioccale M (2010) Gondwana paleolandscapes of Argentina: an introduction. Geociências 29(4):439–466. São Paulo, UNESP
Rabassa J, Carignano C, Cioccale M (2014) A general overview of Gondwana landscapes in Argentina. In: Rabassa J, Ollier C (eds) Gondwana landscapes in southern South America. Springer, Dordrecht, pp 201–245
Ramos V (1999) Las Provincias Geológicas del Territorio Argentino. Instituto de Geología y Recursos Minerales. Geología Argentina. Anales 29(3):41–96. Buenos Aires
Ramos V, Cortés JM (1984) Estructura e interpretación tectónica. IX Congreso Geológico Argentino (San Carlos de Bariloche). Relatorio 1(12):317–346
Rapela CW, Alonso G (1991) Composición litológica y geoquímica del batolito de la Patagonia central. VI Congreso Geológico Chileno, Actas, 1, Viña del Mar, pp 236–240
Romero EJ, Dibbern MC (1984) Floras fósiles Cenozoicas. 9° Congreso Geológico Argentino (San Carlos de Bariloche). Relatorio 2(2):373–382
Thomas MF (1978) The study of inselbergs. Zeitschrift für Geomorphologie. N. F., Suppl. Bd. 31:1–41. Berlin
Twidale CR (1982) Granite landforms. Elsevier, Amsterdam. Pub. Com, 372 p
Twidale CR (1985) Old land surfaces and their implications for models of landscape evolution. Revue Géomorphologie Dynamique 34:131–147
Twidale CR (1987) Etch and intracutaneous forms and their implications. Aust J Earth Sci 34:367–386
Twidale CR (1989) La iniciación subsuperficial de las formas graníticas y sus implicaciones en las teorías generales de la evolución del paisaje. Cuadernos Laboratorio Xeologico de Laxe, 13, Coruña, Spain, pp 49–68
Twidale CR (1990) The origin and implications of some erosional landforms. J Geol 98:343–364
Vidal Romaní JR (1989) Granite geomorphology in Galicia, (NW Spain). Cuadernos Laboratio Xeologico de Laxe, 13, Coruña, Spain, pp 89–163
Vidal Romaní JR, Twidale CR (1998) Formas y paisajes graníticos. Universidade da Coruña, A Coruña, Spain, 411 pp
Volkheimer W (1984) Microfloras fósiles Mesozoicas. IX Congreso Geológico Argentino (San Carlos de Bariloche). Relatorio 2(3):383–391
Wayland EJ (1934) Peneplains and some erosional platforms, Geological survey of Uganda, Annual report and bulletin. Protectorate of Uganda Geological Survey, Department of Mines, Kampala, pp 77–79
Acknowledgments
The authors want to express their deepest gratitude to Professor Cliff Ollier for his valued comments and observations, both in the field in 2001 and on a preliminary version of this manuscript.
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Aguilera, E.Y., Rabassa, J., Aragón, E. (2014). Paleo-landscapes of the Northern Patagonian Massif, Argentina. In: Rabassa, J., Ollier, C. (eds) Gondwana Landscapes in southern South America. Springer Earth System Sciences. Springer, Dordrecht. https://doi.org/10.1007/978-94-007-7702-6_15
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