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Plio-Quaternary volcanism in Ecuador

Published online by Cambridge University Press:  01 May 2009

F. Barberi ,
M. Coltelli ,
G. Ferrara ,
F. Innocenti ,
J. M. Navarro  and
R. Santacroce
F. Barberi
Affiliation:
Dipartimento di Scienze della Terra, University of Pisa, via S. Maria 53, 56100 Pisa, Italy
M. Coltelli
Affiliation:
Dipartimento di Scienze della Terra, University of Pisa, via S. Maria 53, 56100 Pisa, Italy
G. Ferrara
Affiliation:
Dipartimento di Scienze della Terra, University of Pisa, via S. Maria 53, 56100 Pisa, Italy
F. Innocenti
Affiliation:
Dipartimento di Scienze della Terra, University of Pisa, via S. Maria 53, 56100 Pisa, Italy
J. M. Navarro
Affiliation:
Dipartimento di Scienze della Terra, University of Pisa, via S. Maria 53, 56100 Pisa, Italy
R. Santacroce
Affiliation:
Dipartimento di Scienze della Terra, University of Pisa, via S. Maria 53, 56100 Pisa, Italy
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Abstract

Extensive sampling, major element chemistry on over 300 samples and K-Ar radiometric dating have been carried out on the Ecuadorian Upper Tertiary–Quaternary volcanoes. The results show important space–time variations of the volcanic activity, between Late Miocene time and the present. In Late Miocene time a continuous volcanic belt, located approximately along the present volcanic front (VF), affected the whole country from the Cuenca basin to the south, up to Colombia to the north. Major changes occurred at about 5 Ma: volcanic activity stopped south of the Guayaquil fault belt and never resumed; to the north the active volcanic axis shifted eastward to the Cordillera Real (CR) area with a simultaneous relative decrease in intensity. Since Early Quaternary time the volcanic belt widened westward to the Western Cordillera where the volcanism resumed at about 1.5–1.0 Ma, giving rise to the very wide active volcanic zone of Ecuador.

The Plio-Quaternary products show significant longitudinal and latitudinal chemical and mineralogical changes. Volcanics of the VF and Interandean Depression contain amphibole and define a calc-alkaline trend with a K2O content lower than that of the CR products, which are characterized by a mostly anhydrous phenocryst assemblage. In both areas andesites dominate, but extreme compositions (basaltic andesites and rhyolites) are more diffuse in the CR than the VF. No significant transverse zoning has been detected in the northern region (north of the Chota-Mira transverse tectonic line). The observed temporal and spatial variations are interpreted as a result of the subduction of the Carnegie Ridge anomalous oceanic crust, underthrusting of which began approximately 6 Ma ago.

Type
Articles
Information
Geological Magazine , Volume 125 , Issue 1 , January 1988 , pp. 1 - 14
Copyright
Copyright © Cambridge University Press 1988

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References

Almeida, E., Aguilera, E., Barberi, F., Coltelli, M., Innocenti, F., Navarro, J. M. & Santacroce, R. (In prep.). Petrochemical data of Plio-quaternary volcanic rocks from Ecuador.Google Scholar
Baldock, J. W. 1983. Geología del Ecuador (Boletín de la Explication del Mapa Geológico de la República del Ecuador, escala 1:1000000, 1982). Quito: Dirección General de Geología y Minas.Google Scholar
Baldock, J. W. 1985. The Northern Andes: a review of the Ecuadorian Pacific margin. In The Ocean Basins and Margins, The Pacific Ocean, Vol. 7A (ed. Nairn, A. E. M., Stehli, F. G., Uyeda, S.), pp. 181–217. New York, London: Plenum Press.Google Scholar
Barazangi, M. & Isacks, B. L. 1976. Spatial distribution of earthquakes and subduction of the Nazca plate beneath South America. Geology 4, 686–92.Google Scholar
Barazangi, M. & Isacks, B. L. 1979. Subduction of the Nazca plate beneath Peru: evidence from spatial distribution of earthquakes. Geophysical Journal of the Royal Astronomical Society 57, 537–55.Google Scholar
Bristow, C. R. & Hoffstetter, R. 1977. Lexique Stratigraphique International: Ecuador, Vol. 5, 2nd edn. Paris: Centre National de la Recherche Scientifique.Google Scholar
Campbell, C. J. 1974. Ecuadorian Andes. In Mesozoic-Cenozoic Orogenic Belts, Data for Orogenic Studies (ed. Spencer, A. M.), pp. 725–32. London: The Geological Society.Google Scholar
Colony, R. J. & Sinclair, J. H. 1928. The lavas of the volcano Sumaco, Eastern Ecuador, South America. American Journal of Science 16, 299–312.CrossRefGoogle Scholar
Condie, K. C. 1973. Archean magmatism and crustal thickening. Geological Society of America Bulletin 84, 2981–92.Google Scholar
DGGM 1982. Mapa Geológico National de la República del Ecuador, escala 1:1000000. Quito: Dirección General de Geología y Minas.Google Scholar
Dickinson, W. R. 1975. Potash-depth (K-h) relations in continental margin and intra-oceanic magmatic arcs. Geology 3, 53–6.2.0.CO;2>CrossRefGoogle Scholar
Ewart, A. 1982. The mineralogy and petrology of Tertiary–Recent orogenic volcanic rocks: with special reference to the andesitic-basaltic compositional range. In Andesites (ed. Thorpe, R. S.), pp. 25–95. Chichester: John Wiley.Google Scholar
Faucher, B. & Savoyat, E. 1973. Esquisse géologique des Andes de I'Ecuateur. Revue de Géographie Physique et de Géologie Dynamique 15, 115–42.Google Scholar
Feininger, T. 1982. The metamorfic basement of Ecuador. Geological Society of America Bulletin 93, 87–92.2.0.CO;2>CrossRefGoogle Scholar
Feininger, T. & Seguin, M. K. 1983. Simple Bouguer Gravity anomaly field and the inferred crustal structures of continental Ecuador. Geologoy 11, 40–44.Google Scholar
Franzini, M., Leoni, L. & Saitta, M. 1972. A simple method to evaluate the matrix effects in X-ray fluorescence analysis. X-Ray Spectrometry 1, 151–4.Google Scholar
Gill, J. B. 1981. Orogenic Andesite and Plate Tectonics. Berlin, Heidelberg: Springer-Verlag.Google Scholar
Goossens, P. J. & Rose, W. I. Jr 1973. Chemical composition and age determination of tholeiitic rocks in the Basic Igneous Complex, Ecuador. Geological Society of America Bulletin 84, 1043–52.2.0.CO;2>CrossRefGoogle Scholar
Hall, M. L. & Calle, J. 1982. Geochronological control for the main tectonic–magmatic events of Ecuador. Earth-Science Reviews 18, 215–39.CrossRefGoogle Scholar
Hall, M. L. & Wood, C. A. 1985. Volcano-tectonic segmentation of Northern Andes. Geology 13, 203–7.2.0.CO;2>CrossRefGoogle Scholar
Hekinian, R. 1982. Petrology of the Ocean Floor. Elsevier oceanography series, Vol. 33. Amsterdam: Elsevier.Google Scholar
Henderson, W. G. 1979. Cretaceous to Eocene volcanic are activity in the Andes of Northern Ecuador. Journal of the Geological Society of London 136, 367–78.Google Scholar
Hey, R. 1977. Tectonic evolution of the Cocos-Nazca spreading center. Geological Society of America Bulletin 88, 1404–20.Google Scholar
Hormann, P. K. & Pichler, H. 1982. Geochemistry, petrology, and origin of the Cainozoic volcanic rocks of the Northern Andes in Ecuador. Journal of Volcanology and Geothermal Research 12, 259–82.CrossRefGoogle Scholar
Irvine, T. N. & Baragar, W. R. W. 1971. A guide to the chemical classification of the common volcanic rocks. Canadian Journal of Earth Sciences 8, 523–48.CrossRefGoogle Scholar
Kennerley, J. B. 1980. Outline of geology of Ecuador. Overseas Geological & Mineralogical Research 55, 1–17.Google Scholar
Lebrat, M., Megard, F., Juteau, T. & Calle, J. 1985. Preorogenic volcanic assemblage and structure in the Western Cordillera of Ecuador between 1 40'S and 2 20'S. Geologische Rundschau 74/ 2, 343–51.CrossRefGoogle Scholar
Lonsdale, P. 1978. Ecuadorian subduction system. American Association of Petroleum Geologists Bulletin 62, 2454–77.Google Scholar
Marriner, G. F. & Millward, D. 1984. The petrology and geochemistry of Cretaceous to Recent volcanism in Colombia: the magmatic history of an accretionary plate margin. Journal of the Geological Society of London 141, 473–86.Google Scholar
McGeary, S., Nur, A. & Ben-Avraham, Z. 1985. Spatial gap in arc volcanism: the effect of collision or subduction of oceanic plateaus. Tectonophysics 119, 195–221.Google Scholar
Miyashiro, A. 1974. Volcanic rock series in island arcs and active continental margins. American Journal of Science 274, 321–55.CrossRefGoogle Scholar
Nur, A. & Ben-Avraham, Z. 1981. Volcanic gaps and the consumption of aseismic ridges in South America. Geological Society of America Memoirs 154, 729–40.Google Scholar
Olade, , 1980. Informe geo-volcanológico: proyecto de investigation geotermica de la República del Ecuador. Organizatión Latinoamericana de Energía, Quito.Google Scholar
Peccerillo, A. & Taylor, S. R. 1976. Geochemistry of Eocene calc-alkaline volcanic rocks from the Kastamonu Area, Northern Turkey. Contributions to Mineralogy and Petrology 58, 63–81.CrossRefGoogle Scholar
Pennington, W. D. 1981. Subduction of the Eastern Panama Basin and seismotectonics of northwestern South America. Journal of Geophysical Research 86, 10753–70.Google Scholar
Pilger, R. H. Jr 1981. Plate reconstructions, aseismic ridges, and low-angle subduction beneath the Andes. Geological Society of America Bulletin 92, 448–56.2.0.CO;2>CrossRefGoogle Scholar
Pilger, R. H. Jr 1984. Cenozoic plate kinematics, subduction and magmatism: South America Andes. Journal of the Geological Society of London 141, 793–802.Google Scholar
Plate Tectonic Map of the Circum-Pacific Region. 1981. Circum-Pacific Council for Energy and Mineral Resources. American Association of Petroleum Geologists.Google Scholar
Sacks, I. S. 1983. The subduction of young lithosphere. Journal of Geophysical Research 88, 3355–66.CrossRefGoogle Scholar
Simkin, T., Siebert, L., McClell, L., Bridge, D., Newhall, C. & Latter, J. H. 1981. Volcanoes of the World. Smithsonian Institution. Pennsylvania: Hutchinson Ross.Google Scholar
Stauder, W. 1975. Subduction of the Nazca plate under Peru as evidenced by focal mechanisms and by seismicity. Journal of Geophysical Research 80, 1053–64.Google Scholar
Steiger, R. H. & Jäger, E. 1977. Subcomission on geochronology: convention on the use of decay constants in geo- and cosmochronology. Earth and Planetary Science Letters 36, 359–62.Google Scholar
Suarez, G., Molnar, P. & Burchfield, B. C. 1983. Seismicity, fault plane solution, depth of faulting, and active tectonics of the Andes of Peru, Ecuador, and southern Colombia. Journal of Geophysical Research 88, 10403–28.Google Scholar
Thorpe, R. S. & Francis, P. W. 1979. Variations in Andean andesite compositions and their petrogenetic significance. Tectonophysics 57, 53–70.Google Scholar
Thorpe, R. S., Francis, P. W. & O'Callaghan, L. 1984. Relative roles of source composition, fractional crystallization and crustal contamination in the petrogenesis of Andean volcanic rocks. Philosophical Transactions of the Royal Society of London A 310, 675–92.Google Scholar
Thorpe, R. S., Francis, P. W., Hammill, M. & Baker, M. C. W. 1982. The Andes. In Andesites (ed. Thorpe, R. S.), pp. 187–205. Chichester: John Wiley.Google Scholar
Tschopp, H. J. 1953. Oil explorations in the Oriente of Ecuador, 1938–1950. American Association of Petroleum Geologists Bulletin 37, 2303–47.Google Scholar
Zeil, W. 1979. The Andes, a Geological Review. Berlin: Gebrüder Borntraeger.Google Scholar