Analysis of the Aeromagnetic Anomalies of the Auca Mahuida Volcano, Patagonia, Argentina

  • L. M. Longo
  • R. RitisEmail author
  • G. Ventura
  • M. Chiappini
Part of the Pageoph Topical Volumes book series (PTV)


We present the analysis of the subsurface structure of the Auca Mahuida volcano based on high-resolution aeromagnetic data integrated with the available geological information. Most of the detected magnetic anomalies have a dipolar structure opposite to that of the present geomagnetic field. According to the available geochronological data and paleomagnetic measurements, the source bodies of Auca Mahuida mainly emplaced in the Matuyama reverse polarity chron. The Reduction-to-the-Pole map confirms that the magnetization direction is mainly reverse with only few anomalies normally magnetized. Two opposite, coexisting polarities do not allow to fully remove the dipolar character of the field in the Reduction-to-the-Pole transformation. Therefore, we model the measured anomaly field by applying analytical techniques that are independent of the magnetization direction. The obtained anomaly strikes and source geometries indicate an emplacement of intrusive bodies controlled by the regional faults affecting the Auca Mahuida basement and the sedimentary successions of the Neuquén basin. Magma upraised along these faults and fractures feeding the volcanic activity and subsequently crystallized. The averaged power spectrum and Euler Deconvolution indicate source depths consistent with those of the intrusions recognized in wells. Borehole data highlight the widespread presence of intrusive bodies below the Auca Mahuida central crater and the peripheral sectors at depth of 2 km below sea level. These bodies have played a major role in the thermal maturation of hydrocarbons and in the subsequent accumulation of oil below the volcano. The obtained results shed light on the Auca Mahuida feeding system and on the intrusions geometry, also pointing out the effectiveness of the magnetic prospecting in the oil industry even in presence of strong remanent magnetization.


Magnetic anomalies aeromagnetic data oil fields and volcanoes reverse polarity Auca Mahuida volcano 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Atchuta Rao, D., Ram Babu, H.V., and Sanker Narayan, P.V., 1981, Interpretation of magnetic anomalies due to dikes: the complex gradient method. Geophysics, 46, 1572–1578.CrossRefGoogle Scholar
  2. Barbosa V., Silva J. and Mediros, W., 1999, Stability analysis improvement of structural index estimation in Euler Deconvolution. Geophysics, 64, 48–60.CrossRefGoogle Scholar
  3. Barbosa V., Silva J. and Mediros, W., 2000, Making Euler Deconvolution applicable to small ground magnetic surveys. Journal of Applied Geophysics, 43, 55–68.CrossRefGoogle Scholar
  4. Blakely, R.J., and Grauch, V.J.S., 1983. Magnetic models of crystalline terrane: accounting for the effect of topography. Geophysics, 48, 1551–1557.CrossRefGoogle Scholar
  5. Blanco-Montenegro I., l Torta J. M., García A., Araña V., 2003, Analysis and modeling of the aeromagnetic anomalies of Gran Canaria (Canary Islands). Earth and PlanetaryScienceLetters, 206, 601–616.CrossRefGoogle Scholar
  6. Blanco-Montenegro, I., De Ritis, R., & Chiappini M., 2006. Imaging and modeling the subsurface structure of volcanic calderas with high-resolution aeromagnetic data at Vulcano (Aeolian islands, Italy), B. Volcanol., 69 (6), p. 643–659, doi: 10.1007/s00445-006-0100-7.CrossRefGoogle Scholar
  7. Bermúdez, A., Delpino, D., 1998, Estudio de testigos corona de rocas ígneas intrusivas reservorios de hidrocarburos y de las secuencias del Volcán Auca Mahuida. Repsol YPF. Unpublished report.Google Scholar
  8. Blakely, R. J. Potential Theory in Gravity and Magnetic Applications (Cambridge University Press, New York, 1995)Google Scholar
  9. Brisson, I., and Veiga, V., 1999, YPF internal report.Google Scholar
  10. Carson Aereogravity, 2001,VolcánAucaMahuida and Señal Cerro Bayo Exploration Lots (March 28, 2001 - June 10, 2001). For YPF S.A., Argentina. Data Processing Report.Google Scholar
  11. Cristallini, E.O., Bottesi, G., Gavarrino, A., Rodriguez, L., Tomezzoli, R., Comeron, R., 2006, Synrift geometry of the Neuquén Basin in the northeastern Neuquén Province, Argentina, InEvolution of the Andean margin: a tectonic and magmatic view from the Andes to the Neuquén Basin (35◦–39◦ 422 latitude): Geological Society of America. eds. Kay, S. M. and Ramos, V. A.). Special Paper 407, pp. 147–161.Google Scholar
  12. De Ritis, R., Blanco-Montenegro, I., Ventura, G., Chiappini, M., 2005, Aeromagnetic data provide new insights on the volcanism and tectonics of Vulcano Island and offshore (Southern Tyrrhenian Sea, Italy), Geophysical Research Letters, 32, L15305, doi: 10.1029/2005GL023465.
  13. Finn, C., Sisson, T. W. & Deszcz-Pan, M., 2001. Aerogeophysical measurements of collapse-phrone hydrothermally altered zones at Mount Rainer volcano, Nature, 409, 600–603.CrossRefGoogle Scholar
  14. Gunn P.J., 1997, Quantitative methods for interpreting aeromagnetic data: a subjective review. AGSO Journal of Australian Geology & Geophysics, 17(2), 105–113.Google Scholar
  15. Hsu, S., 2002, Imaging magnetic sources using Euler´s equation. Geophysical Prospecting, 50, 15–25.CrossRefGoogle Scholar
  16. Kay, S.M., and Ramos, V.A., 2006, Evolution of an Andean Margin: A tectonic and magmatic view from the Andes to the Neuquén Basin (35°–39°S): Geological Society of America, Special Papers, v. 407, 19–60,  10.1130/2006.2407(02).
  17. Longo, L.M., Ravazzoli, C.L.,Chiappini, M., 2008, Proyecto de interpretación de datos aerogravimétricos y magnéticos en el Volcán Auca Mahuida. Cuarto encuentro ciéntifico del ICES (E-ICES4), Malargüe, Mendoza, Argentina.Google Scholar
  18. MacLeod, I.N, Jones, K., Fan Dai, D., 1993, 3-D analytic signal in the interpretation of total magnetic field data at low magnetic latitudes. Explor. Geophys., 24, 679-688.Google Scholar
  19. MacLeod, I.N., Ellis, R.G., Magnetic Vector Inversion, a simple approach to challenge of varying direction of rock magnetization.23 rd International Geophysical conference and exhibition, 11–14 August 2013. ASEG-PESA 2013Melbourne, Australia.Google Scholar
  20. Mosquera, A. and Ramos, V.A., 2006, Intraplate deformation in the Neuquén Basin, In: Kay S.M. and Ramos, V.A., eds. Evolution of an Andean margin: a tectonic and magmatic view from the Andes to the Neuquén Basin (35◦–39◦S latitude). Geological Society of America Special Paper, 407, 97–124.Google Scholar
  21. Mushayandebvu, M.,Van Driel, P., Reid, A. and Fairhead, J., 2001, Magnetic source parameters of two-dimensional structures using extended Euler Deconvolution. Geophysics, 66, 814-823.CrossRefGoogle Scholar
  22. Nabighian, N.M., 1972, The analytic signal of two-dimensional magnetic bodies with polygonal cross section: its properties and used for automated anomaly interpretation. Geophysics 37, 507-517.CrossRefGoogle Scholar
  23. Nabighian, N.M., 1984, Toward a three-dimensional automatic interpretation of potential field data via generalized Hilbert transforms: fundamental relations, Geophysics 49, 780-786.CrossRefGoogle Scholar
  24. Pángaro, F., Villar, H., Vottero, A., Bojarski, G., Rodríguez Arias, L., 2004, Eventos volcánicos y sistemas petroleros: El caso del Volcán Auca Mahuida, Cuenca Neuquina, Argentina. IX Congreso Latino americano de Geoquímica orgánica, México, 23-27.Google Scholar
  25. Ramos, V.A. and Folguera, A., 2010, Payenia volcanic province in the Southern Andes: an appraisal of an exceptional Quaternary tectonic setting: Journal of Volcanology and Geothermal Research, v. 201, 53–64, doi: 10.1016/j.jvolgeores.2010.09.008.CrossRefGoogle Scholar
  26. Reid, A., Allsop, J. Granser, H., Millet, A. and Somerton, I., 1990, Magnetic interpretation in three dimensions using Euler Deconvolution. Geophysics, 55, 80-91.CrossRefGoogle Scholar
  27. Reynolds J. M., An Introduction to Applied and Environmental Geophysics (John Wiley & Sons, 2011-2nd Edition)Google Scholar
  28. Roest, W.R Verhoeff, J. Pilkington, M., 1992. Magnetic interpretation using the 3-D analytic signal. Geophysics 57, 116–125.CrossRefGoogle Scholar
  29. Rossello, E.A., Cobbold, P.R., Diraison, M., and Arnaud. N., 2002, Aucamahuida (Neuquén basin, Argentina): A Quaternary shield volcano on a hydrocarbon-producing substrate, in 6th International Symposium on Andean Geodynamics (ISAG 2002). Extended Abstracts, Barcelona, Univ. De Barcelona: Instituto Geologico y Minero de España, 549–552.Google Scholar
  30. Sigismondi, M. and Ramos, V., 2008,El flujo de calor de la cuenca Neuquina, Argentina. VII Congreso Exploración y Desarrollo (Simposio de La Geofísica: Integradora del conocimiento del subsuelo).Google Scholar
  31. Spector, A. and Grant, F.S., 1970, Statistical models for interpreting aeromagnetic data, Geophysics, 35, 293–302.CrossRefGoogle Scholar
  32. Thompson, D., 1982, EULDPH: A new technique for making computer-assisted depth estimates form magnetic data. Geophysics, 47, 31–37.CrossRefGoogle Scholar
  33. Vela R., Sancho V., Fasola M., 2006, Integración de datos geoquímicos en el desarrollo del yacimiento volcán Auca Mahuida. III Workshop de Geoquimica de Sistemas Petroleros, Quito, Ecuador, Abril 2006.Google Scholar
  34. Ventura, G., De Ritis, R., Longo, M., Chiappini, M., 2012, Terrain characterization and structural control of the Auca Mahuida volcanism (Neuquén Basin, Argentina): International Journal of Geographical Information Science, v. 27, 1469-1480, doi: 10.1080/13658816.2012.741241.CrossRefGoogle Scholar
  35. Vottero, A., Rodríguez, L., Vela, R., 2005, Trampas de hidrocarburos en el centro este de la Cuenca Neuquina. VI Congreso de Exploración y Desarrollo de Hidrocarburos- Las trampas de hidrocarburos en las cuencas productivas de Argentina, 189–208.Google Scholar

Copyright information

© Springer Basel 2015

Authors and Affiliations

  • L. M. Longo
    • 1
    • 2
  • R. Ritis
    • 3
    Email author
  • G. Ventura
    • 3
    • 4
  • M. Chiappini
    • 3
  1. 1.YPF, Gerencia de GeofísicaBuenos AiresArgentina
  2. 2.Facultad de Ciencias Astronómicas y GeofísicasUniversidad Nacional de La PlataLa PlataArgentina
  3. 3.Istituto Nazionale di Geofisica e VulcanologiaRomeItaly
  4. 4.Istituto Ambiente Marino CostieroConsiglio Nazionale delle RicercheNaplesItaly

Personalised recommendations