1887
Volume 72, Issue 3
  • E-ISSN: 1365-2478

Abstract

Abstract

The Ordovician–Devonian Sierra Grande Formation, Río Negro Province, Argentina contains three quarzitic members with two iron horizons. Its South Deposit includes both iron horizons. However, the East Deposit is relatively unknown, lacking information about geometry, depth and reserves. To answer these questions, we apply geophysical methods for the rapid evaluation of the East Deposit, using gravity and magnetic measures. The processing of these data allows the suggestion of two 2D models for calculating thicknesses, angles and depth of the iron horizons. The adjustments between the calculated and the observed curve are less than 6%. One model proposes the existence of the Alfaro iron horizon, and the other one proposes the presence of the Rosales iron horizon at depth. The Bouguer anomaly gravimetric maps allow us to calculate the mineral mass, resulting in 125 million iron tons. Thus, this study allowed us to calculate the thicknesses, angles and depth of both iron horizons, and to adjust and evaluate the mineral reserves with the maximum reliability that potential methods allow when applied to mineral prospecting. These results provide new and valuable information for future mining prospects.

Loading

Article metrics loading...

/content/journals/10.1111/1365-2478.13458
2024-02-21
2025-01-20
Loading full text...

Full text loading...

References

  1. Ávila, J.C. (1980) Estructura geológica del Yacimiento Sur de Sierra Grande, provincia de Río Negro. Acta Geológica Lilloana xv, (2), 85–102, Tucumán.
    [Google Scholar]
  2. Ávila, J.C. (1982) Problemas geológicos estructurales en la explotación minera de Sierra Grande, provincia de Río Negro. Revista del lnstituto de Ciencias Geológicas, 5, 141‐169, Jujuy.
    [Google Scholar]
  3. Bahía, M.E., Longo, L.M., Ravazzoli, C.L., Scivetti, N., Benedini, L., Marcos, P. et al. (2021) Modeling and structural inversion from gravimetric data of the San Jorge Gulf Basin, Argentina. Journal of South American Earth Sciences, 112, 103606.
    [Google Scholar]
  4. Baranov, V. (1957) A new method for interpretation of aeromagnetic maps: pseudo‐gravimetric anomalies. Geophysics, 22(2), 359–382.
    [Google Scholar]
  5. Buggisch, W. (1987) Stratigraphy and very low‐grade metamorphism of the Sierras Australes de la Provincia de Buenos Aires (Argentina) and implications in Gondwana correlation. Zentralbatt für Geologie Paläontologie, 5(1), 819–837.
    [Google Scholar]
  6. Busteros, A., Giacosa, R., Lema, H. & Zubía, M. (1998) Hoja Geológica 4166‐IV, Sierra Grande: Vol. 241 Buenos Aires, Provincia de Río Negro. Servicio Geológico Minero Argentino (SEGEMAR). Boletín, p. 75.
  7. Caminos, R., and Llambías, E. J. (1984) El basamento cristalino. In: Geología y Recursos Naturales de la provincia de Río Negro. Buenos Aires, IX Congreso Geológico Argentino, Relatorio, I(2), 37–63.
  8. Cortés, M. (1979) Primeros afloramientos de la Formación Sierra Grande en la provincia del Chubut. In: VII Congreso Geológico Argentino, Actas, vol. 1. Buenos Aires, pp. 481–487.
  9. Cortés, J.M. (1981) El sustrato precretácico del extremo nordeste de la provincia del Chubut. Revista de la Asociación Geológica Argentina, 36(3), 217–235.
    [Google Scholar]
  10. Cortés, J. M., Caminos, R. & Leanza, H. (1984) La cobertura sedimentaria eopaleozoica. In Ramos, V. (Ed.) Geología y Recursos Naturales de la Provincia de Río Negro, vol. I‐3. pp. 65–84, Buenos Aires.
    [Google Scholar]
  11. de Alba, E. (1964) Descripción Geológica de la Hoja 41j, Sierra Grande [Boletín No. 97]. Buenos Aires: Dirección Nacional de Geología y Minería. p. 67.
    [Google Scholar]
  12. DEMAG . (1963) Estudio geológico de los yacimientos Norte, Sur y Este de Sierra Grande, Rio Negro [HIPASAM, informe inédito]. Buenos Aires: HIPASAM.
    [Google Scholar]
  13. Fanton, G., Martínez, P. & Giménez, M. (2014) Procesamiento y analisis cualitativo de datos aeromagneticos con vistas a la exploración de yacimientos hidrotermales tipo lode gold‐provincia de La rioja, Argentina. Geoacta, 39(1), 30–50.
    [Google Scholar]
  14. Gelós, E.M. (1977) Metamorfismo de contacto en el Yacimiento Sur de Sierra Grande, provincia de Río Negro. Revista de la Asociación Geológica Argentina, 32(2), 99–110.
    [Google Scholar]
  15. Giacosa, R. & Paredes, J. M. (2001) Estructura de las metamorfitas del Paleozoico temprano en el Arroyo. Salado. Macizo Nordpatagónico, Río Negro. Revista de la Asociación Geológica Argentina, 56(2), 141–149.
    [Google Scholar]
  16. González, P., Varela, R., Sato, A., Campos, H., Greco, G., Naipauer, M. et al. (2008) Metamorfismo regional ordovícico y estructura de la ectinita El Jagüelito al SO de Sierra Grande, Río Negro. In: XVIICongreso Geológico Argentino, San Salvador de Jujuy. Vol. 2. pp. 849–850.
  17. González, P.D., Tortello, M.F. & Damborenea, S.E. (2011) Early Cambrian archaeocyathan limestone blocks in low‐grade meta‐conglomerate from El Jagüelito Formation (Sierra Grande, Río Negro, Argentina). Geologica Acta, 9(2), 159–173.
    [Google Scholar]
  18. Goussev, S. (2022) Gravity and magnetic encyclopedic dictionary. Houston: Society of Exploration Geophysicists, pp. 362.
    [Google Scholar]
  19. Gregori, D.A., Kostadinoff, J., Strazzere, L. & Raniolo, A. (2008) Tectonic significance and consequences of the Gondwanide orogeny in northern Patagonia, Argentina. Gondwana Research, 14(3), 429–450.
    [Google Scholar]
  20. Gregori, D.A., Kostadinoff, J., Alvarez, G., Raniolo, A., Strazzere, L., Martínez, J.C. et al. (2013) Preandean geological configuration of the eastern North Patagonian Massif, Argentina. Geoscience Frontiers, 4(6), 693–708.
    [Google Scholar]
  21. Hinze, W.J., von Frese, R.R., von Frese, R. & Saad, A. H. (2013) Gravity and magnetic exploration: principles, practices, and applications. Cambridge, UK: Cambridge University Press.
    [Google Scholar]
  22. Keidel, J. (1916) La geología de las sierras de la Provincia de Buenos Aires y sus relaciones con las montañas de Sudáfrica y los Andes.Ministerio de Agricultura de La Nación, Sección Geología. Mineralogía y Minería, Anales v. XI(3),1–78.
    [Google Scholar]
  23. Macmillan, S. & Maus, S. (2005) International Geomagnetic Reference Field—the tenth generation. Earth, Planets and Space, 57(12), 1135–1140.
    [Google Scholar]
  24. Marson, I. & Klingele, E.E. (1993) Advantages of using the vertical gradient of gravity for 3‐D interpretation. Geophysics, 58(11), 1588–1595.
    [Google Scholar]
  25. Massabie, A.C. & Rossello, E.A. (1984) La discordancia pre‐formación Sauce Grande y su entorno estratigráfico, Sierras Australes de la Provincia de Buenos Aires. 9°Congreso Geológico Argentino, Actas 1: 337–352, San Carlos de Bariloche.
  26. Miller, H.G. & Singh, V. (1994) Potential field tilt—a new concept for location of potential field sources. Journal of Applied Geophysics, 32(2–3), 213–217.
    [Google Scholar]
  27. Milligan, P. R. & Gunn, P. J. (1997) Enhancement and presentation of airborne geophysical data. AGSO Journal of Australian Geology and Geophysics, 17(2), 63–75.
    [Google Scholar]
  28. Müller, H. (1965) Zur Altersfrage der Eisenerzlagerstätte Sierra Grande/Río Negro in Nordpatagonien Aufgrund Neuer Fossilfunde. Geologische Rundschau, 54(2), 715–732.
    [Google Scholar]
  29. Nabighian, M.N. (1972) The analytic signal of two‐dimensional magnetic bodies with polygonal cross‐section: its properties and use for automated anomaly interpretation. Geophysics, 37(3), 507–517.
    [Google Scholar]
  30. Nettleton, L.L. (1976) Gravity and magnetics in oil prospecting. New York: McGraw Hill, pp. 212–215.
    [Google Scholar]
  31. Núñez, E., Bachmann, E., Ravazzoli, I., Britos, A., Franchi, M., Lizuain, A. et al. (1975) Rasgos geológicos del sector oriental del macizo de Somuncurá, Provincia de Río Negro, República Argentina. In: Congreso Iberoamericano de Geología Económica, vol. 2. pp. 247–266.
  32. Pankhurst, R.J., Rapela, C.W., Fanning, C.M. & Márquez, M. (2006) Gondwanide continental collision and the origin of Patagonia. Earth‐Science Reviews, 76(3–4), 235–257.
    [Google Scholar]
  33. Pavón Pivetta, C., Gregori, D., Benedini, L., Garrido, M., Strazzere, L., Geraldes, M., et al. (2020) Contrasting tectonic settings in Northern Chon Aike Igneous Province of Patagonia: subduction and mantle plume‐related volcanism in the Marifil formation. International Geology Review, 62(15), 1904–1930.
    [Google Scholar]
  34. Ramos, V.A. (1975) Geología del Sector Oriental del Macizo Nordpatagónico entre Aguada Capitán y la Mina Gonzalito, Provincia de Río Negro. Revista de la Asociación Geológica Argentina, 30(3), 274–285. Buenos Aires.
    [Google Scholar]
  35. Reid, A., FitzGerald, D. & McInerny, P. (2003) Euler deconvolution of gravity data. In: SEG Technical Program Expanded Abstracts 2003. Houston, TX: Society of Exploration Geophysicists, pp. 580–583.
    [Google Scholar]
  36. Roest, W.R., Verhoef, J. & Pilkington, M. (1992) Magnetic interpretation using the 3‐D analytic signal. Geophysics, 57(1), 116–125.
    [Google Scholar]
  37. Roy, L., Agarwal, B.N.P. & Shaw, R.K. (2000) A new concept in Euler deconvolution of isolated gravity anomalies. Geophysical Prospecting, 48(3), 559–576.
    [Google Scholar]
  38. Sharma, P.V. (1986) Geophysical methods in geology, Englewood Cliffs, NJ: P.T.R. Prentice Hall, pp. 133–134.
    [Google Scholar]
  39. Sheriff, R.E. (2002) Encyclopedic dictionary of applied geophysics. Houston: Society of Exploration Geophysicists, p. 442.
    [Google Scholar]
  40. Stavrev, P.Y. (1997) Euler deconvolution using differential similarity transformations of gravity or magnetic anomalies. Geophysical Prospecting, 45(2), 207–246.
    [Google Scholar]
  41. Stipanicic, P.N., Rodrigo, F.E.L.I.X., Baulies, O.L. & Martínez, C.G. (1968) Las formaciones presenonianas en el denominado Macizo Nordpatagónico y regiones adyacentes. Revista de la Asociación Geológica Argentina, 23(2), 67–98.
    [Google Scholar]
  42. Strazzere, L., Gregori, D.A., Benedini, L., Marcos, P., Barros, M.V., Geraldes, M.C. et al. (2019) The Puesto Piris formation: evidence of basin‐development in the North Patagonian Massif during crustal extension associated with Gondwana breakup. Geoscience Frontiers, 10(1), 299–314.
    [Google Scholar]
  43. Strazzere, L., Pavon Pivetta, C., Gregori, D.A., Benedini, L., Geraldes, M.C. & Barros, M.V. (2022) The Marifil Volcanic Complex at Sierra de Pailemán: implications for the Early Jurassic magmatic evolution of the Eastern North Patagonian Region. International Geology Review, 64(6), 844–866.
    [Google Scholar]
  44. Talwani, M., and Heirtzler, J.R. (1964) Computation of magnetic anomalies caused by two‐dimensional bodies of arbitrary shape. In: Parks, G.A. (Ed.) Computers in the mineral industries, Part 1, vol. 9. Stanford: Geological Sciences, Stanford Univ. Publ., pp. 464–480.
    [Google Scholar]
  45. Tankard, A., Welsink, H., Aukes, P., Newton, R. & Stettler, E. (2009) Tectonic evolution of the Cape and Karoo basins of South Africa. Marine and Petroleum Geology, 26(8), 1379–1412.
    [Google Scholar]
  46. Telford, W.M., Telford, W.M., Geldart, L. & Sheriff, R.E. (1990) Applied geophysics, vol. 1. Cambridge: Cambridge University Press.
    [Google Scholar]
  47. Thurston, J.B. & Smith, R.S. (1997) Automatic conversion of magnetic data to depth, dip, and susceptibility contrast using the SPI (TM) method. Geophysics, 62(3), 807–813.
    [Google Scholar]
  48. Vacquier, V., Steenland, N.C., Henderson, R.G. & Zietz, I. (1951). Interpretation of aeromagnetic maps. Memoir of the Geological Society of America 47. Boulder, CO: Geological Society of America
    [Google Scholar]
  49. Valvano, J.A. (1954) Génesis de los yacimientos de Hierro de Sierra Grande. Revista de la Asociación Geológica Argentina, 9(4), 193–209.
    [Google Scholar]
  50. Varela, R., Cingolani, C., Sato, A., Dalla Salda, L., Brito Neves, B.B., Basei, M.A.S. et al. (1997) Proterozoic and paleozoic evolution of Atlantic area of North‐Patagonian Massif, Argentine. San Pablo (Brasil), I South American Symposium on Isotope Geology, Acta, 326–329.
  51. Varela, R., Basei, M.A.S., Sato, A.M., Siga, O., Cingolani, C.A. & Sato, K. (1998) Edades isotopicas Rb/Sr y U/Pb en rocas de Mina Gonzalito y Arroyo Salado. Macizo Norpatagonico Atlantico, Rio Negro, Argentina. Buenos Aires,X Congreso Latinoamericano de Geología y VI Congreso Nacional de Geología Económica, I(Actas), 71–76.
  52. Verduzco, B., Fairhead, J.D., Green, C.M. & MacKenzie, C. (2004) New insights into magnetic derivatives for structural mapping. The Leading Edge, 23(2), 116–119.
    [Google Scholar]
  53. von Gosen, W. (2002). Polyphase structural evolution in the northeastern segment of the North Patagonian Massif (southern Argentina). Journal of South American Earth Sciences, 15(6), 591–623.
    [Google Scholar]
  54. von Gosen, W. (2003) Thrust tectonics in the North Patagonian Massif (Argentina): implications for a Patagonia plate. Tectonics, 22(1).
    [Google Scholar]
  55. Wichmann, R. (1919) Contribución a la geología de la Región comprendida entre el Rio Negro y Arroyo Valcheta. In: Anales del Ministerio de Agricultura de la Nación (SEC. Geología, mineralogía y minería, XIII), vol. 4. Houston: Society of Exploration Geophysicists, pp. 1–44.
    [Google Scholar]
  56. Zanettini, J.C. (1981) La formación Sierra Grande (provincia de Río Negro). Revista de la Asociación Geológica Argentina, 36(2), 160–179.
    [Google Scholar]
  57. Zanettini, J.C.M. (1999) Los depósitos ferríferos de Sierra Grande, Río Negro. In: ZappettiniE.O. (Ed.) Recursos Minerales de la República Argentina, vol. 35. Buenos Aires: Instituto de Geología y Recursos Minerales, Servicio Geológico Minero Argentino, Anales. pp. 745–762.
    [Google Scholar]
/content/journals/10.1111/1365-2478.13458
Loading
/content/journals/10.1111/1365-2478.13458
Loading

Data & Media loading...

  • Article Type: Research Article
Keyword(s): gravity; magnetics; modelling; potential field

Most Cited This Month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error