Abstract
THE past decade has seen a rapid advance in our understanding of the deep structure of the continental crust, especially in Europe1–3, Australia4 and North America5, where seismic profiling has revealed a highly reflective layer in the lower crust. On many profiles, the reflective layer is associated with regions of extension6,7, suggesting that the reflectors originate by some form of ductile flow or magmatic intrusion during rifting8,9. To test this hypothesis, we have examined geophysical and geological data from the Valencia trough, a rift basin10–12 of Late Oligocene/Early Miocene age. From a comparison of profiles in different parts of the trough, and independent constraints on the initial crustal thickness, we argue that the reflective layer in this basin was probably already in the crust before rifting, and that a mid-Tertiary extensional event is not required to explain it.
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References
BIRPS & ECORS J. geol. Soc. Land. 143, 45–52 (1986).
DEKORP Research Group J. Geophys. 57, 137–163 (1985).
DEKORP Research Group Tectonophysics 173, 199–206 (1990).
Mathur, S. P. Tectonophysics 100, 163–173 (1983).
Allmendinger, R., Hauge, T., Hausser, E., Potter, C. & Oliver, J. Spec. Publ. geol. Soc. Lond. 28, 223–246 (1987).
Mathews D. H. & Cheadle M. in Reflection Seismology Geodyn. Ser. Vol. 13, 5–20 (American Geophysical Union, Washington, DC, 1986).
Reston, T. J. Tectonics 7, 929–945 (1988).
Meissner, R. & Kusznir, N. J. Ann. Geophys. B5, 365–374 (1987).
Mathews, D. H. & BIRPS Geophys. J. R. astr. Soc. 89, 209–215 (1987).
Julivert, M., Fontbote, J. M., Ribeiro, A. & Conde, L. N. Memoria Explicativa del Mapa tectónico de la Peninsula Ibérica y Baleares (Institute Geologico y Minero de Espan̄a, Madrid. 1972).
Mauffret, A. Mém. Soc. géol. France 132, 1–96 (1977).
Banda, E., Ansorge, J., Boloix, M. & Cordoba, D. Earth planet Sci. Lett. 49, 219–230 (1980).
Torné, M. & Banda, E. II Congreso Geológico de España (Proc.) Vol. 2, 219–222 (Sociedad Geologica de España, Granada, 1988).
Stoffa, P. L. & Buhl, P. J. geophys. Res. 84, 7645–7663 (1979).
Contribution de la exploracion petrolifera al cononcimiento de la Geologia de España (Instituto Geológico y Minero de España, Madrid, 1987).
Bois, C., Pinet, B. & Roure, F. in Properties and Processes of Earth's Lower Crust Vol. 6, 17–31 (Am. geophys. Un., Washington, DC, 1989).
Hobbs, R. W., Peddy, C. & BIRPS group Geophys. J. R. astr. Soc. 89, 239–242 (1987).
Chadwick, R. A., Pharon, T. C. & Smith, N. J. P. J. geol. Soc. Lond. 146, 617–630 (1989).
Marillier, F., Tomassino, A., Patriat, P. & Pinet, B. Mar. Petrol. Geol. 5, 65–74 (1988).
Blundell, D. J. The Potential of Deep Seismic Profiling for Hydrocarbon Exploration (eds Pinet, B. & Bois, C.), 317–334 (Technip, Paris, 1990).
Mooney, W. D. & Brocher, T. M. Geophys. J. R. astr. Soc. 89, 1–6 (1987).
Zeyen, H. J., Banda, E., Gallart, J. & Ansorge, J. Earth planet. Sci. Lett. 75, 393–402 (1985).
Peddy, C. et al. J. geol. Soc. Lond. 146, 427–437 (1989).
Torné, M. et al. Terra Abstr. 2, 119 (1990).
Cox, K. G. J. Petrol. 21, 621–650 (1980).
Watts, A. B. & Ryan W. F. Tectonophysics 36, 25–44 (1976).
Sawyer, D. J. J. geophys. Res. 90, 7751–7769 (1985).
McKenzie, D. P. Earth planet. Sci. Lett. 40, 25–32 (1978).
Jarvis G. T. & McKenzie, D. P. Earth planet. Sci. Lett. 48, 42–52 (1980).
Cochran, J. R. Earth planet. Sci. Lett. 66, 289–302 (1983).
Hsu, K. I., Cita, M. B. & Ryan W. B. F. Init. Rep. DSDP Leg 42, 943–949 (1977).
Dañobeitia, Ju. J., Alonso, B. & Maldonado, A. Mar. Geol. (in the press).
Long, R. E. & Backhouse, R. W. Geophys. J. R. astr. Soc. 44, 677–688 (1976).
Woollard, G. P. Bur. Gravimetrique Int. Bull. d'Inform. 36, 106–110 (1975).
LASE study group. Mar. Petrol Geol. 3, 234–242 (1986).
White, R. S. et al. Geophys. J. R. astr. Soc. 89, 265–272 (1987).
ECORS Pyrenees Team Nature 331, 508–511 (1988).
Marti, J., Grachev, A., Mitjavila, J., Aparicio, A. & Roca, E. Terra Abstr. 2, 114 (1990).
International Bathymetric Chart of the Mediterranean (Intergovernmental Oceanographic Commission).
Stoffa, P. L., Diebold, J. B. & Buhl, P. Geophys. Prosp. 30, 25–57 (1982).
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Watts, A., Torné, M., Buhl, P. et al. Evidence for reflectors in the lower continental crust before rifting in the Valencia trough. Nature 348, 631–635 (1990). https://doi.org/10.1038/348631a0
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DOI: https://doi.org/10.1038/348631a0
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