Structure of the Marathon basin (NE Attica, Greece) based on gravity measurements


S. Chailas
A. Tzanis
E. Lagios
Résumé

This work presents the results of a high resolution gravity survey conducted in the area of Marathon Basin to asses the structure of the basement. A total of 120 gravity stations were measured. Standard data reduction procedures were followed, albeit based on modern, high precision techniques. The inversion of the Bouguer anomaly map provided a rather detailed image of the basement topography completing the information available from surface geological and morphological surveys. The major structural features of the Marathon Basin appear to be controlled by a system of NE-SW neotectonic faults causing stepwise NW-SE deepening of the basement to a maximum detectable depth of~450m. These faults, together with a system of NW-SE major, and a host of minor faulting features, lend to the Basin characteristics of a Riedel structure formed by a predominantly N-S extensional field effecting clockwise block rotation. This mode of deformation may also have facilitated the formation of local anticlinal/ synclinal structures, which endow the area with its rather complicated morphology. Finally, the multiple intersecting faults appear to form a permeable network, presumably responsible for the salination of the local aquifer system; the NE-SW major normal faults may the most significant contributor to this effect.

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  • Rubrique
  • Geophysics and Seismology
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Références
Boetechtel, J., and Papadeas, G., 1968. Tectonic aereal interpretation in the Mediterranean region exemplified by the metamorphic series at eastern Greece, near Marathon, Photogrammetria, 26, 201-210.
Bott, M.H.P., 1960. The use of rapid digital computing methods for direct gravity interpretation of sedimentary basins, Geoph. J.R. astr. Soc, 38(4), 253-264.
Cartwright, D.E., and Edden, A.C., 1973. Corrected tables of tidal harmonics, Geoph. J.R. astr. Soc, 33,253-264.
Cartwright, D.E., and Tayler, R.J., 1971. New computations of the tide-generating potential, Geoph. J.R. astr. Soc., 23, 45-74.
Featherstone, W. E., and Dentith, M. C, 1997. A geodetic approach to gravity data reduction for geophysics, Computers & Geosciences, 23(10), 1063-1070.
Featherstone, W. E., 1995. The Global Positioning System and its use in geophysical exploration, Exploration Geophysics, 26(1), 1-18
Goumas, G., 2006. Exploring the structure of Thriasion Plain with geophysical methods, MSc Thesis, Faculty of Geology and Geoenvironment, University of Athens.
Hammer, S., 1939. Terrain corrections for gravimeter stations, Geophysics, 4, 184-194.
Lagios, E., 1979. Gravity and other geophysical studies relating to the crustal structure of southeast Scotland, PhD Thesis, Edinburgh University, 309pp.
Lagios, E., Chailas, S., and Hipkin, R.G., 1996. Newly Compiled Gravity and Topographic Data Banks of Greece, Geoph. J. Intern. 126, 287-290.
Lozios, S., 1991. Microtectonic observations in the metamorphic system of the Varnavas – Ramnounta area, NE Attica, Bull. Geol. Soc. Greece, 25(1), 439-453. (in Greek)
Lozios, S., 1993. Tectonic analysis of the metamorphic formations of NE Attica, PHD Thesis, University of Athens, 299pp. (in Greek)
Makris, J., and Stavrou, Α., 1984. Compilation of gravity maps of Greece, Technical Report, Institute of Geological and Mining Exploration, Athens.
Margonis, S., Syridis, G., Psilovikos, A.R., Trontsios, G. Steinhauer, G., Vouvalidis, Κ., and Mouzouris, G, 2002. The evolution of the natural environment in the area of Schinias wetlands, Marathon, from the ancient era to date, Proceedings, 6th Panhellenic Geographical Congress, Thessaloniki, October 2002, 159-165. (in Greek)
Margonis, S., 2006. Investigation of the environmental processes of the evolution of the Marathon Plain wetlands during the Holocene using Geographical Information Systems (G.I.S.), PhD Thesis, Aristotle University of Thessaloniki, 164pp. (in Greek)
Maroukian, H., Zamani, Α., and Pavlopoulos, K., 1993. Coastal retreat in the Plain of Marathon (east Attica), Greece: cause and effects, Geologica Balcanica, 23, 67-71.
Melissaris, P., and Stavropoulos, X., 1999. HydrogeologicaI Study of the Marathon Plain, Attica, Department of Geology - Hydrogeology, Ministry of Agricultural Development, (in Greek)
Mettos, Α., 1992. Geological and Palaeogeographical study of the Terrestrial Neogene and Quartenary formations of NE Attica and SE Beotea, PhD Thesis, University of Athens, 259pp. (in Greek)
Morelli, C., Gantar, C, Honkasalo, T., McConnell. R. K., Tanner, J. G., Szabo, B., Uotila, U., and Whalen, C.T., 1974. The international gravity standardisation net (I.G.S.N. 71), IAG Specia 1 Publication No. 4, 194pp.
Pavlopoulos, K., Karkanas, P., Triantaphyllou, M., Karymbalis, E., Tsourou, Th., and Palyvos, N., 2006. Paleoenvironmental Evolution of the Coastal Plain of Marathon, Greece, during the Late Holocene: Depositional Environment, Climate, and Sea Level Changes, Journal of Coastal Research, 22 (2), 424-438.
Radhakrishna Murthy, I.V., Rama Rao, P., and Jagannardha Rao, S., 1990. The density difference and generalized programms for two and three-dimensional gravity modeling., Computers & Geosciences, 16(3), 277-287.
Radhakrishna Murthy, I.V., Rama Rao, P., and Ramakrishna, P., 1989. Gravity Anomalies of Three-dimensional Bodies with Variable Density Contrast, PAGEOPH, 130(4), 711-719.
Seni, A, Kapsimalis V, and Pavlopoulos, K., 2004. Determination of recent géomorphologie changes in the Marathonas coastal plain (Attica, Greece), using geographical information systems, 6th Panhellenic Geographical Congress, Mytilini, Greece, October 2004. (in Greek, available at http://www.ath.aegean.gr/srcosmos)
Stavropoulos, X., and Tzima, M., 2001. Investigation related to the salt intrusion mechanisms of Kato Souli springs, Marathonas, Attiki, Bull. Geol. Soc. Greece, XXXIV/5, 1967-1972.
Swain, C.J., and Khan, M.A., 1977. A catalogue of gravity data in Kenya, Leicester University Publications.
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