New microscopic evidences of the autochthony of the ferralliticpedological mantle in the Misiones Province, Argentina

Autores/as

  • Lucas M. Moretti INTA-CIRN, Instituto de Suelos. N. Repetto y Los Reseros S/N (1712) Castelar, Buenos Aires, Argentina
  • Héctor J. M. Morras INTA-CIRN, Instituto de Suelos. N. Repetto y Los Reseros S/N (1712) Castelar, Buenos Aires, Argentina

Palabras clave:

Soils, Microscopy, Weathering, Basalt, Misiones Province.

Resumen

The Misiones province is characterized by a pedological mantle with Ultisols, Oxisols and Alfisols. This ferrallitic clayey material frequently shows one or more siliceous or ferruginous nodular “stony horizons” close to the saprolitized basalt, which are generally associated with “structured horizons”. The autochthonous or allochthonous origin of the materials composing these complex profiles has been controversially discussed. In this work, we present the results of new microscopic analyses of thin sections and of sand and silt fractions from several profiles of this pedological mantle. The results show that the “nodular horizons” are formed in the massive basalts by weathering and segregation of saprolitized fragments, which become progressively rounded, ferruginized and indurated. Concurrently, the groundmass in- between the nodules is enriched in clay and iron oxides, developing blocky peds, which gives rise to the “structured horizons”. On the other hand, the vesicular porosity fossilized by chalcedony in the solum of a profile demonstrates the residual origin of the soil parent material, developed by the weathering of a vesicular- amygdaloidal basalt bearing hydrothermal quartz veins. In turn, the morphology and the surface texture of quartz grains from the sand and silt fractions analyzed by optical microscopy and by scanning electron microscopy reveal processes of silica dissolution and precipitation and show no signals of eolian transport. In accordance with previous studies, these microscopic results provide clear evidence that the parent material of soils in the Misiones province and the “stony horizons” usually included in these profiles are the result of in situ weathering of the diverse basaltic flows outcropping in the region.

Citas

Causevic, H., H. Morrás, A. Mijovilovich and C. Saragovi, 2004. Evidences of the stability of magnetite in a soil from northeastern Argentina by Mössbauer spectroscopy and magnetization measurements. Physica B: Physics of Condensed Matter 354:373-376.

Ciccioli, S., L. Garrido and J. Gómez, 2005. Aspectos mineralógicos de los basaltos de Eldorado, Provincia de Misiones, orientados a su posible utilización en la industria cerámica. XVI Congreso Geológico Argentino Actas I:855-862, La Plata.

Delvigne, J., 1998. Atlas of micromorphology of mineral alteration and weathering. The Canadian Mineralogist-ORSTOM. Special publication 3, 494 pp.

Eswaran H. and G. Stoops, 1979. Surface texture of quartz in tropical soils. Science Society of America Journal 43:420-424.

Fedoroff, N., M.A. Courty and Z. Guo, 2010. Paleosols and Relict soils. In G. Stoops, V. Marcelino and F. Mees (Eds.), Interpretations of Micromorphological Features of Soils and

Regoliths, Elsevier, Amsterdam: 623-662.

Iriondo, M. and D. Kröhling, 1997. The tropical loess. In A. Zhisheng and Z. Weijian (Eds.), Proceedings 30th International Geological Congress 21:61-77.

Iriondo, M. and D. Kröhling, 2004. The parent material as the dominant factor in Holocene pedogenesis in the Uruguay River basin. Revista Mexicana de Ciencias Geológicas 21:175- 184.

Krinsley, D. and J. Doornkamp, 1973. Atlas of sand quartz surface textures. Cambridge University Press, 91 pp.

Kröhling, D. and M. Iriondo, 2010. Comment on “Genesis of subtropical soils with stony horizons in NE Argentina: Autochthony and polygenesis” by Morrás et al. Quaternary International 227:190-192.

Lagorio, S. and P. Leal, 2005. Caracterización geoquímica de vulcanitas tholeíiticas de la Formación Serra Geral en laprovincia de Misiones. XVI Congreso Geológico ArgentinoActas I:605-610, La Plata.

Le Ribault, L., 1977. L´exoscopie des quartz. Collection: Techniques et méthodessédimentologiques. Masson, Paris, 150 pp.

Marengo, H. and Y. Palma, 2005. Diques y coladas en los basaltos de Serra Geral, área de San Ignacio, Misiones. XVI Congreso Geológico Argentino Actas I:487-492, La Plata.

Marengo, H., Y. Palma, P. Tchilingurian, F. Helms, W. Kruck and D. Roverano, 2005. Geología del área de San Ignacio, Provincia de Misiones. XVI Congreso Geológico Argentino Actas I:141-148, La Plata.

Márquez, R., J. Martín-García, G. Delgado, J. Bech and R. Delgado, 2010. Genesis of the quartz in Spanish Mediterranean soils. An advance. 19th World Congress of Soil Science Abstracts S02.4.1:69-72, Brisbane, Australia.

Márquez, R., J. Bech, J. Martín-García, G. Delgado and R. Delgado, 2012. Crystalline idiomorfism like neoformation sign of quartz grains in mediterranean soils. 4th International Congress of the European Confederation of Soil Science Societies Abstracts S02.01-P-5, Bari, Italia.

Mijovilovich, A., H. Morrás, C. Saragovi, G. Santana and J. Fabris, 1998. Magnetic fraction of an Ultisol from Misiones, Argentina. Hyperfine Interactions C3:332-335.

Moretti, L., H. Morrás, W. Zech and G. Píccolo, 2006. Origen y evolución paleoambiental del manto ferralítico de la provincia de Misiones. III Congreso Argentino de Cuaternario y Geomorfología Actas II:753-762, Córdoba.

Morrás, H., L. Moretti, G. Píccolo and W. Zech, 2005. Nueva hipótesis acerca del origen de las líneas de piedras y horizontes estructurados subsuperficiales en los suelos ferralíticos de Misiones, Argentina. XVI Congreso Geológico Argentino Actas V:97-102, La Plata.

Morrás, H., L. Moretti, G. Píccolo and W. Zech, 2006. Stone lines and weathering profiles of ferrallitic soils in northeastern Argentina. In D. Langouche and E. Van Ranst (Eds.), New Waves in Physical Land Resources. International Centre for Physical Land Resources, Rijksuniversiteit Gent, Belgium: 269-280.

Morrás, H., L. Moretti, G. Píccolo and W. Zech, 2009. Genesis of subtropical soils with stony horizons in NE Argentina: Autochthony and polygenesis. Quaternary International 196:137-159.

Morrás, H., L. Moretti, G. Píccolo and W. Zech, 2010. A reply to D. Kröhling and M. Iriondo´s comment on “Genesis of subtropical soils with stony horizons in NE Argentina: Autochthony and polygenesis” by Morrás et al. Quaternary International 227:193-195.

Rabassa, J., C. Carignano and M. Cioccale, 2010. Gondwanapaleosurfaces in Argentina: An introduction. Geociências 29:439-466.

Riggi, J. and N. Riggi, 1964. Meteorización de basaltos en Misiones.Revista de la Asociación Geológica Argentina XIX:57-70.

Sanesi, G., 1965. I souli di Misiones. Academia Italiana di ScienzeForestali, 343 pp.

Ségalen, P., 1994. Les solsferrallitiques et leurrépartitiongeógraphique. ORSTOM Éditions, Office de la RechercheScientifique et Techniqued’Outre-Mer, Paris, Tome1, 198 pp. Stoops, G., 1967. Le profild´alteration au Bas-Congo (Kinshasa).Sa description et sagenèse. Pédologie XVII:60-105.

Stoops, G., 2003. Guidelines for analysis and description of soil and regolith thin sections. Soil Science Society of America,

Madison, Wisconsin, USA, 184 pp.

Teruggi, M., 1955. Los basaltos tholeíiticos de Misiones. Notas Museo de La Plata XVIII, Geol. N° 70:259-278.

Zech, M., R. Zech, H. Morrás, L. Moretti and B. Glaser, 2009. LateQuaternary environmental changes in Misiones, subtropical NE Argentina, deduced from multi-proxy geochemical analyses in a palaeosol-sediment sequence. Quaternary International 196:121-136.

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Publicado

2021-03-31

Cómo citar

Moretti, L. M. ., & Morras, H. J. M. . (2021). New microscopic evidences of the autochthony of the ferralliticpedological mantle in the Misiones Province, Argentina. Latin American Journal of Sedimentology and Basin Analysis, 20(2), 129-142. Recuperado a partir de https://lajsba.sedimentologia.org.ar/index.php/lajsba/article/view/148

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