Abstract
Areas which are geodynamically different have different behaviors both in their thermal regime and seismic activity. A stable area has a geotherm which can be considered as standard, extensional and compressional areas have, respectively, high and low temperature gradients. The Italian region includes different geodynamical areas and all such situations are present. We consider the Apulian platform as an example of a stable area and the Tuscany-Latium as an example of an extensional area. For both of them the present geotherms are calculated, taking into account, for the Tuscany-Latium, its thermal history. Assuming that each region is subject to a constant strain rate, the stresses are calculated as functions of depth and time. The rheological behavior is assumed to be linear viscoelastic, with viscosity dependent on temperature and elastic parameters dependent on lithology. The geothermal profile and the rheological structure of the lithosphere remarkably affect the processes of stress accumulation which control the distribution of seismic activity. The abrupt decrease of the temperature gradient at the Moho produces considerably higher stress values with respect to the case of uniform gradient, thus favoring subcrustal seismicity. In the case of a standard temperature gradient, subcrustal seismicity is predicted and a gap in seismicity, indicating a soft intracrustal layer, exists if there is a discontinuity in rheology. By contrast, in the case of a high-temperature gradient, subcrustal seismicity is not to be expected, even in the presence of a discontinuity in rheology, since subcrustal temperatures are already too high to permit a sufficient stress accumluation.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Baldi, P., Bertini, G., Cameli, G. M., Decandia, F. A., Dini, I., Lazzarotto, A., andLiotta, D. La tettonica distensiva post-collisionale nell'area geotermica di Larderello (Toscana meridionale). InStudi Geologici Camerti, Volume speciale 1994/1 (eds. Lazzarotto, A., and Liotta, D.) (Università di Camerino, Italy, 1994) pp. 183–193.
Calcagnile, G., andPanza, G. F. (1980),The Main Characteristics of the Lithosphere-asthenosphere System in Italy and Surrounding Regions, Pure and Appl. Geophys.119, 865–879.
Cameli, G. M., Dini, I., andLiotta, D. (1993),Upper Crustal Structure of the Larderello Geothermal Field as a Feature of Post-collisional Extensional Tectonics (Southern Tuscany, Italy), Tectonophysics224, 413–423.
Caputo, M., Panza, G. F., andPostpischl, D. (1970),Deep Structure of the Mediterranean Basin, J. Geophys. Res.75, 4919–4923.
Cermak, V. andRybach, L. L.,Thermal conductivity and specific heat of minerals and rocks. InNumerical Data and Functional Relationships in Science and Technology (ed. Landolt-Börnstein), Physical Properties of Rocks (Springer-Verlag, Berlin 1982) pp. 305–341.
Chen, W. P., andMolnar, P. (1983),Focal Depth of Intracontinental and Intraplate Earthquakes and their Implications for the Thermal and Mechanical Properties of the Lithosphere, J. Geophys. Res.88, 4183–4214.
Christensen, R. M.,Theory of Viscoelasticity: An Introduction (Academic Press, New York 1971) 245 pp.
Console, R., Di Giovanbattista, R., Favali, P., andSmriglio, G. (1989),Lower Adriatic Sea Seismic Sequence (January 1986): Spatial Definition of the Seismogenic Structure, Tectonophysics166, 235–246.
Doglioni, C. (1991),A Proposal of Kinematic Modelling for W-dipping Subductions-possible Applications to the Tyrrhenian-Apennines System, Terra Nova3, 423–434.
Doglioni, C. (1992),Main Differences between Thrust Belts, Terra Nova,4, 152–164.
Doser, D. I., andKanamori, H. (1986),Depth of Seismicity in the Imperial Valley Region (1977–1983) and its Relationship to Heat Flow, Crustal Structure and the October 15, 1979, Earthquake, J. Geophys. Res.91, 675–688.
Dragoni, M. (1988),A Model of Interseismic Stress Evolution in a Transcurrent Shear Zone, Tectonophysics.149, 265–273.
Dragoni, M. (1993),The Brittle-ductile Transition in Tectonic Boundary Zones, Annali di Geofisica36, 37–44.
Dragoni, M., Bonafede, M., andBoschi, E. (1986),Shallow Earthquakes in a Viscoelastic Shear Zone with Depth-dependent Friction and Rheology, Geophys. J. R. Astr. Soc.86, 617–633.
Dragoni, M., andPondrelli, S. (1991),Depth of the Brittle-ductile Transition in a Transcurrent Boundary Zone, Pure and Appl. Geophys.135, 447–461.
Dragoni, M., Santini, S., andTallarico, A. (1993),A Viscoelastic Shear Zone Model of Compressional and Extensional Plate Boundaries, Pure and Appl. Geophys.140, 471–491.
Favali, P., Funiciello, R., Mattietti, G., Mele, G., andSalvini, F. (1993),An Active Margin Across the Adriatic Sea (Central Mediterranean Sea), Tectonophysics219, 109–117.
Finetti, I. (1982),Structure, Stratigraphy and Evolution of Central Mediterranean, Boll. Geofis. Teor. Appl.24, 247–315.
Ghisetti, F., Scarpa, R., andVezzani, L. (1982),Seismic Activity, Deep Structures and Deformation Processes in the Calabrian Arc, Southern Italy, Earth Evol. Sci.3, 248–260.
Giardini, D., andVelonà, M. (1991),Deep Seismicity of the Tyrrhenian Sea, Terra Nova3, 57–64.
Kirby, S. H., andKronenberg, A. K. (1987),Rheology of the Lithosphere: Selected Topics, Rev. Geophys.25, 1219–1244.
Lachenbruch, A. H. (1970),Crustal Temperature and Heat Production: Implications of the Linear Heat Flow Relation, J. Geophys. Res.75, 3291–3300.
Malinverno, A., andRyan, W. B. F. (1986),Extension in the Tyrrhenian Sea and Shortening in the Apennines as a Result of Arc Migration Driven by Sinking of the Lithosphere, Tectonics5, 227–245.
McKenzie, D. (1978),Some Remarks on the Development of Sedimentary Basins, Earth Planet. Sci. Lett.40, 25–32.
Meissner, R., andStrehlau, J. (1982),Limits of Stresses in Continental Crusts and their Relations to the Depth-frequency Distribution of Shallow Earthquakes, Tectonics1, 73–89.
Mongelli, F., Loddo, M., andCalcagnile, G. (1975),Some Observations on the Apennines Gravity field, Earth Plan. Sci. Lett.24, 385–393.
Mongelli, F., Loddo, M., andTramacere, A. (1982),Thermal Conductivity, Diffusivity and Specific Heat Variation of Some Travale (Tuscany) Rocks versus Temperature, Tectonophysics83, 33–43.
Mongelli, F., Zito, G., Ciaranfi, N., andPieri, P. (1989),Interpretation of Heat Flow Density on the Apennine Chain, Italy, Tectonophysics164, 267–280.
Mongelli, F., Zito, G., Della Vedova, B., Pellis, G., Squarci, P., andTaffi, L.,Geothermal regime of Italy and surrounding seas. InExploration of the Deep Continental Crust: Terrestrial Heat Flow and the Lithosphere) (Cermak, V., and Rybach, L. L., eds), (Springer-Verlag, Berlin 1991) pp. 381–394.
Moretti, I., andRoyden, L. (1988),Deflection, Gravity Anomalies and Tectonics of a Doubly Subducted Continental Lithosphere: Adriatic and Ionian Seas, Tectonics7, 875–893.
Morgan, P., Seager, W. R., andGolombek, M. P. (1986),Cenozoic Thermal, Mechanical and Tectonic Evolution of the Rio Grande Rift, J. Geophys. Res.91, 6263–6276.
Nicolich, R., andPellis, G. (1979),Il contributo dei dati geofisici per lo studio delle strutture crostali della provincia geotermica tosco-laziale, Contributo28, Ist. Min. Geofis. Appl., Univ. Trieste.
Panza, G. F. (1984),The Deep Structure of the Mediterranea-Alpine Region and Large Shallow Earthquakes, Mem. Soc. Geol. It.29, 3–11.
Panza, G. F., Mueller, S., Calcagnile, G., andKnopoff, L. (1982),Delineation of th Central Italian Upper Mantle Anomaly, Nature296, 238–239.
Pescatore, T., andSenatore, M. R. (1986):A comparison between a present-day (Taranto Gulf) and a Miocene (Irpinia Basin) foredeep of the Southern Apennines (Italy). InForeland Basins: Spectal Publication of the International Association of Sedimentologists (Allen, P. A., and Homewood, P., eds.),8, 169–182.
Prescott, W. H., andNur, A. (1981),The Accommodation of Relative Motion at Depth on the San Andreas Fault System in California, J. Geophys. Res.86, 999–1004.
Ranalli, G.,Rheology of the Earth (Allen & Unwin, Boston 1987).
Ricchetti, G., andMongelli, F. (1980),Flessione e campo gravimetrico della micropiastra apula, Boll Soc. Geol. It.99, 431–436.
Royden, L., Patacca, E., andScandone, P. (1987),Segmentation and Configuration of Subducted Lithosphere in Italy: An Important Control on Thrust-belt and Foredeep-basin Evolution, Geology15, 714–717.
Scarascia, S., Lozej, A., andCassinis, R. (1994),Crustal Structures of the Ligurian, Tyrrhenian and Ionian Seas and Adjacent Onshore Areas Interpreted from Wide-angle Seismic Profiles, Boll. Geofis. Teor. Appl.,36, 5–19.
Selvaggi, G., andAmato, A. (1992),Subcrustal Earthquakes in the Northern Apennines (Italy): Evidence for a Still Active Subduction?, Geophys. Res. Lett.19, 2127–2130.
Serri, G. (1990),Neogene-Quaternary Magmatism of the Tyrrhenian Region: Characterization of the Magma Sources and Geodynamic Implications, Mem. Soc. Geol. It.41, 219–242.
Sibson, R. H. (1974),Frictional Constraints on Thrust, Wrench and Normal Faults, Nature249, 542–544.
Sibson, R. H. (1982),Fault Zone Models, Heat Flow and the Depth Distribution of Earthquakes in the Continental Crust of the United States, Bull. Seismol. Soc. Am.72, 151–163.
Spakman, W. (1989),Tomographic Images of the Upper Mantle below Central Europe and the Mediterranean, Terra Nova2, 542–553.
Turcotte, D. L., Liu, J. Y., andKulhawy, F. H. (1984),The Role of an Intracrustal Asthenosphere on the Behavior of Major Strike-slip Faults, J. Geophys. Res.89, 5801–5816.
Zoth, G., andHaenel, R. Appendix. InHandbook of Terrestrial Heat Flow Density Determination (Haenel, R., Rybach, L., and Stegena, L., eds.), (Kluwer Acad. Publ., Dordrecht 1988) pp. 449–453.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Dragoni, M., Doglioni, C., Mongelli, F. et al. Evaluation of stresses in two geodynamically different areas: Stable foreland and extensional backarc. PAGEOPH 146, 319–341 (1996). https://doi.org/10.1007/BF00876496
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00876496