Geothermal models of the crust and uppermost mantle of the Fennoscandian Shield in South Norway and the Danish Embayment
Article Sidebar
Vols. 1-18 (1924-1944), ISSN 0044-2801
Main Article Content
Abstract
A narrow heat flow transition zone between the Fennoscandian Shield and the North Sea Basin has been investigated along a profile from the Precambrian of South Norway to the Danish Embayment in North Jylland. Along this profile the surface heat flow varies from about 42 mWm-2 (measured) in South Norway to 60–70 mWm-2 (estimated) in Denmark. Geothermal, seismic, gravity and other geophysical and geological data have formed the basis for construction of heat production and thermal conductivity models in the depth interval 0–50 km. The related steady-state temperatures and heat flow distributions are calculated by a numerical solution of the heat conduction equation in two dimensions. Three models are presented, a preferred model and two others which yield temperatures assumed to be close to the lowest and highest possible values. The preferred model gives temperatures of about 350 °C at the crust-mantle boundary in the Shield and approximately 700 °C beneath the Danish Embayment. These differences are associated with considerable variations in the heat flow from the mantle. In the main model variations from 16-17 mWm-2 in the shield region to about 40 mWm-2 in the Danish Embayment have been found. Some geophysical and petrological implications are discussed. In the sedimentary basin partial melting in the lower crust and at shallow depth in the uppermost mantle seems to be likely.
ARK: https://n2t.net/ark:/88439/y020204
Permalink: https://geophysicsjournal.com/article/254
Article Details
References
Barth, T.F.W., Dons, J.A. (1960) Precambrian of Southern Norway. In: Holtedal, O. (Ed.) Geology of Norway, Norges geol. Unders. 208:6-67
Birch, F., Clark, H. (1940) The thermal conductivity of rocks and its dependence upon temperature and composition. Am. J. Sci. 238, 529-558 and 613-635
Bridgman, P.W. (1924) Thermal conductivity and compressibility of several rocks under high pressures. Am. J. Sci. Ser. 5(7):81-102
Buntebarth, G. (1973) Modellberechnungen zur Temperatur-Tiefen-Yerteilung im Bereich der Alpcn und des Alpenvorlandes. J. Geophys. 39:97-107
Casten, U., Hirschleber, H. (1971) Seismic measurements in Jutland 1969. J. Geophys. 37:47-69
Čermak, Y. (1975) Temperature-depth profiles in Czechoslovakia and some adjacent areas derived from heat-flow measurements, deep seismic sounding and other geophysical data. Tectonophysics 26:103-119
Čermak, V., Jessop, A.M. (1971) Heat flow, heat generation and crustal temperature in the Kapuskasing area of the Canadian Shield. Tectonophysics 11:287-303
Clark, S.P. (1957) Radiative transfer in the Earth's mantle. Trans. Am. Geophys. Union 38:931-938
Clark, S.P. (1969) Heat conductivity in the mantle. In: Hart, P.J. (Ed.) The Earth's crust and upper mantle, Am. Geophys. Un. Geophys. Mon. 13:622-626
Evans, T.R., Coleman, N.C. (1974) North Sea geothermal gradients. Nature 247:28-30
Falkum, T. (1966) Structural and petrological investigations of the Precambrian metamorphic and igneous charnockite and migmatite complex in the Flekkefjord area. Southern Norway. Norges geol. Unders. 242:19-25
Falkum. T. (1972) On large-scale tectonic structures in the Agder-Rogaland region, Southern Norway. Norsk geol. Tidsskr. 52:371-376
Fujisawa. H., Fujii, N., Mizutani. H., Kanamori. H., Akimoto, S. (1968) Thermal diffusivity of Mg2SiO4, Fe2SiO4, and NaCl at high pressures and temperatures. J. Geophys. Res. 73:4727-4733
Fukao, Y. (1969) On the radiative heat transfer and the thermal conductivity in the upper mantle. Bull. Earthquake Res. Inst. 47:549-569
Fukao, Y., Mizutani, H., Uyeda. S. (1968) Optical absorption spectra at high temperatures and radiative thermal conductivity of olivines. Phys. Earth Planet. Interiors l:57-62
Green, T.H. (1967) An experimental investigation of sub-solidus assemblages formed at high pressure in high-alumina basalt, kyanit eclogite and grosspydite compositions. Contr. Mineral. Petrol. 16:
84-114
Green, D.H. (1973) Contrasted melting relations in a pyrolite upper mantle under mid-oceanic ridge. stable crust and island arc environments. In: Wyllie, P.J. (Ed.) Experimental petrology and global tectonics, Tectonophysics 17:285-297
Green, D.H., Ringwood, A.E. (1967) An experimental investigation of the gabbro to eclogite transformation and its petrological applications. Geochim. Cosmochim. Acta 31:767-833
Green, D.H., Ringwood, A.E. (1972) A comparison of recent experimental data on the gab bro-garnet granulite-eclogite transition. J. Geol. 80:277-288
Gregersen, S. (1971) The Trans-Scandinavian seismic profile of 1969, profile section 4-5. In: Vogel, A. (Ed.) Deep seismic sounding in Northern Europe, Swedish Nat. Sci. Res. Council, 92-95
Haenel, R. (1971) Heat flow measurements and a first heat flow map of Germany. J. Geophys. 37:975-992
Hacncl. R., Gronlie, G., Heier, K.S. (1974) Terrestrial heat flow determinations from lakes in Southern Norway. Norsk. geol. Tidsskr. 54:423-428
Heier, K.S., Adams, J.A.S. (1965) Concentration of radioactive elements in deep crustal material. Geochim. Cosmochim. Acta 29:53-61
llirschleber, H., Hjelme, J., SellevolL M.A. (1966) A refraction profile through the Northern Jutland. Geodret. Inst. Medd. Kobenhavn 41:35
Horai. K., Simmons, G. (1969) Thermal conductivity of rock-forming minerals. Earth Planet. Sci. Lett. 6:359-368
Hurtig, E., Brugger, H. (1970) Warmeleitfahigkeitsmessungen unter einaxialem Druck. Tectonophysics 10:67-77
Ito, K., Kennedy. G.C. (1970) The fine structure of the basalt-eclogite transition. Mineral. Soc. Am. Spec. Paper 3:77-83
Ito, K., Kennedy, G.C. (1971) An experimental study of the basalt-garnet granulite-eclogite transition. In: Haecock, J.G. (Ed.) The structure and physical properties of the Earth's crust, Am. Geophys. Un. Geophys. Mon. 14:303-314
Kanestrom, R., Haugland, K. (1971) Crustal structure in southeastern Norway from seismic refraction measurements. Scientific Report No. 5. Seismological Observatory, University of Bergen. Norway, 72 p.
Kappelmeyer, O., Haenel, R. (1974) Geothermics with Special Reference to Application. Geoexpl. Monogr. Ser. I, No. 4:238
Kawada, K. (1964) Variation of the thermal conductivity of rocks. part I. Bull. Earthquake Res. Inst. 42:631-647
Kawada, K. (1966) Variation of the thermal conductivity of rocks. part 2. Bull. Earthquake Res. Inst. 44:1071-1091
Kennedy, G.C., Ito. K. (1972) Comments on: "A comparison of recent experimental data on the gabbrogarnet granulite-eclogite transition". J. Geol. 80:289-292
Killeen, P.G., Heier. K.S. (1974) Radioelement variation in the Levang granite-gneiss, Bambie region, South Norway. Contrib. Mineral. Petrol. 48:171-177
Killeen, P.G., Heier, K.S. (1975a) A uranium and thorium enriched province of the Fennoscandian shield in Southern Norway. Geochim. Cosmochim. Acta 39:1515-1524
Killeen, P.G., Heier. K.S. (1975b) Radioelement distribution and heat production in Precambrian granitic rocks, Southern Norway. Skr. Norske Videnskaps-Akad. I. Mat.-Naturv. kl. 35:32
Lachenbruch, A.H. (1970) Crustal temperature and heat production: Implications of the linear heat-flow relation. J. Geophys. Res. 75:3291-3300
Lambert, L.B., Heier, K.S. (1967) The vertical distribution of uranium, thorium and potassium in the continental crust. Geochim. Cosmochim. Acta 31:377-390
Larsen, G. (1966) Rhaetic-Jurassic-Lower Cretaceous Sediments in the Danish Embayment. Dan marks geol. Unders. II, 91
Larsen, O. (1971) K/Ar age determinations from the Precambrian of Denmark. Dan marks geol. Unders. II. 97:37
Larsen. O. (1972) Kalium/Argon datering af prover fra danskc dybdeboringer. Dansk geol. Foren. Arsskrift for 1971:9I-94
Madsen, L. (1975) Approximate geothermal gradients in Denmark and the Danish North Sea sector. Danmarks geol. Unders. Arbog 1974:5-16
Majorowicz, J.A. (1973) Heat flow data from Poland. Nat. Phys. Sci. 241:16-17
Masse. R.P. (1975) Baltic Shield crustal velocity distribution. Bull. Seismol. Soc. Am. 65:885-897
Parasnis, D.S. (1975) Temperature phenomena and heat flow estimates in two Precambrian ore-bearing areas in North Sweden. Geophys. J. 43:531-554
Puranen, M., Jarvimaki, P., Hamalainen, U., Lehtinen, S. (1968) Terrestrial heat flow in Finland. Geoexploration 6:151-162
Rasmussen, L.B. (1972) Oversigt over dybdeboringerne pa dansk landomrade 1965-68. Dansk geol. Foren .. Arsskrift for 1971:41-48
Rasmussen, L.B. (1974) Some geological results from the first five Danish exploration wells in the North Sea. Geol. Surv. Denmark III Ser. 42:46
Ringwood. A.E. (1969) Composition and evolution of the upper mantle. In: Hart, P.J. (Ed.) The Earth's crust and upper mantle, Am. Geophys. Un. Geophys. Mon. 13:1-17
Roy. R.F., Blackwell, D.D., Birch, F. (1968) Heat generation of plutonic rocks and continental heat flow provinces. Earth Planet. Sci. Lett. 5:1-12
Roy. R.F., Blackwell, D.D., Decker, E.R. (1972) Continental heat flow. In: Robertson, E.C. (Ed.) Nature of the solid Earth, pp. 506-543. McGraw-Hill, New York
Schatz, J.F., Simmons, G. (1972) Thermal conductivity of Earth materials at high temperatures. J. Geophys. Res. 77:6966-6983
Sellevoll, M.A. (1973) Mohorovičić discontinuity beneath Fenneoscandia and adjacent parts of the Norwegian Sea and the North Sea. In: Mueller, S. (Ed.) The structure of the Earth's crust, based on seismic data, Tectonophysics 20:359-366
Sellevoll, M.A., Aalstad, I. (1971) Magnetic measurements and seismic profiling in the Skagerrak. Marine Geophys. Res. 1:284-302
Sellevoll, M.A., Warrick, R.E. (1971) Refraction study of the crustal structure in Southern Norway. Bull. Seism. Soc. Am. 61:457-471
Shaw, D.M. (1967) Uranium, thorium and potassium in the Canadian Precambrian shield and possible mantle compositions. Geochim. Cosmochim. Acta 31:1111-1113
Smithson, S.B. (1965) The nature of the "granitic" layer of the crust in the southern Norwegian Precambrian. Norsk geol. Tidsskr. 45:113-133
Smithson, S.B., Decker, E.R. (1974) A continental crustal model and its geothermal implications. Earth Planet. Sci. Lett. 22:215-225
Sorgenfrei, T. (1969) Geological perspectives in the North Sea area. Bull. geol. Soc. Denmark 19:160-196
Sorgenfrei, T., Buch, A. (1964) Deep tests in Denmark 1935-1959. Dan marks geol. Unders. Ill, 36:146
Swanberg, C.A. (1972) Vertical distribution of heat generation in the Idaho batholith. J. Geophys. Res. 77:2508-2513
Swanberg, C.A., Chessman, M.D., Simmons, G., Smithson, S.B., Grnnlie, G., Heier, K.S. (1974) Heat-flowheat-generation studies in Norway. Tectonophysics 23:31-48
Walsh, J.B., Decker, E.R. (1966) Effect of pressure and saturating fluid on the thermal conductivity of compact rock. J. Geophys. Res. 71:3053-3061
Weigel, W., Hjelme, J., Sellevoll, M.A. (1970) A refraction profile through the Skagerrak from Northern Jutland to Southern Norway. Geodret. Inst. Medd. K0benhavn 45:27
Wenk, H.-R., Wenk, E. (1969) Physical constants of alpine rocks (density, porosity, specific heat, thermal diffusivity and conductivity). Schweiz. Min. Petr. Mitt. 49:343-357
Wesierska, M. (1973) A study of terrestrial heat flux density in Poland. Publ. Inst. Geoph. Pol. Ac. Sci. 60:135-144
Winkler, H.G.F. (1974) Petrogenesis of Metamorphic Rocks. 3rd ed., 320 p. Springer, Berlin-Heidelberg-New York