Abstract
This study aims to determine the central Andean geothermal structure by downward continuation of the surfcace temperature field. The heat flow density values along a trans-Andean profile show a minimum of 40 mW/m2 in the region of the Coastal Cordillera and Chaco and a maximum of 80 mW/m2 in the Western Cordillera and the western Altipiano. The necessary structural data are provided by deep seismic sounding measurements. The petrophysical parameters used for this study are taken from the literature. Steady state and one-dimensional conditions and pure conductive heat transport are assumed. For the region with heat flow values between 40 and 50 mW/m2 the temperature at the base of the crust does not exceed 700 °C. But in the zones with high heat flow density values of 60–80 mW/m2 the temperature in the lower crust reaches values exceeding 1000 °C. Such high temperatures seem to be unrealistic. In order to lower the temperature gradient an additional advective heat transfer is postulated. For the advecting material (fluids and volatiles) a Darcy velocity of about 1 mm/year results. For comparison the amount of upstreaming fluids and volatiles released by the downgoing oceanic crust is determined. This rough estimation yields the amount of fluids pervading the hanging lithosphere and is in the order of 0.3 mm/year. Because most parameters used for these calculations are only estimates the result may vary by a factor of 0.2–5 Finally the rheological response has been determined as the maximum possible stress as a function of depth for the different heat flux locations and a strain rate of 710-15 s-1.
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References
Anderson RN, DeLong SE, Schwarz WM (1978) Thermal model for subduction with dehydration in the downgoing slab. J Geol 86: 731–739
Andrews DJ, Sleep NH (1974) Numerical modelling of tectonic flow behind island arcs. Geophys J R Astr Soc 38: 237 257
Cermak V, Bodri L (1986) Two-dimensional temperature modelling along five East-European geotraverses. J Geodyn 5: 133–163
Fowler CMR (1990) The solid earth, an introduction to global geophysics. Cambridge University Press, Cambridge, 472 pp
Fyfe WS, Lonsdale P (1981) Ocean floor hydrothermal activity. In: Emiliani C (ed) The oceanic lithosphere, the sea 7. Wiley, New York, pp 589–638
Henry SG (1981) Terrestrial heat flow overlying the Andean subduction zone. PhD Thesis, The University of Michigan, 194 pp
Henry SG, Pollack HN (1988) Terrestrial heat flow above the Andean subduction zone in Bolivia and Peru. J Geophys Res 93 (12): 15153–15162
Park RG (1988) Geological structures and moving plates. Blackie, Glasgow, 337 pp
Peacock SM (1987) Thermal effects of metamorphic fluids in subduction zones. Geology 15: 1057–1060
Peacock SM (1989) Thermal modelling of metamorphic pressure-temperarture-time paths: A forward approach. In: Spear S S, Peacock S M (eds) Metamorphic pressure-temperature-time paths. Short Course Presented at the 28th Int Geol Congr, American Geophys Union, Washington DC, pp 57–102
Shi Y, Wang CY (1987) Two-dimensional modeling of the P-T-t paths of regional metamorphism in simple overthrust terrains. Geology 15: 1048–1051
Toksöz MN, Minear JW, Julian BR (1971) Temperature field and geophysical effects of a downgoing slab. J Geophys Res 76: 1113–1138
Uyeda S, Watanabe T (1982) Terrestrial heat flow in Western South America. In: Gupta ML (ed) Terrestrial heat flow. Tectonophysics 83: 63–70
Vitorello I, Hamza VM, Pollack HN (1980) Terrestrial heat flow in the Brazilian highlands. J Geophys 85 (B7): 3778–3788
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© 1994 Springer-Verlag Berlin Heidelberg
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Giese, P. (1994). Geothermal Structure of the Central Andean Crust — Implications for Heat Transport and Rheology. In: Reutter, KJ., Scheuber, E., Wigger, P.J. (eds) Tectonics of the Southern Central Andes. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-77353-2_4
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DOI: https://doi.org/10.1007/978-3-642-77353-2_4
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