CRUSTAL STRUCTURE BENEATH REPUBLIC OF NORTH MACEDONIA BASED ON RECEIVER FUNCTION ANALYSIS
DOI:
https://doi.org/10.46763/GEOL25392139nKeywords:
receiver function; crustal structure; Moho depthAbstract
Teleseismic waveforms recorded by Wideband Ranger WR-1 seismometers at three permanent stations of the Seismological Network of the Republic of North Macedonia: Skopje (SKO), Valandovo (VAY) and Ohrid (OHR), were analyzed using the P receiver function method, which enables identification of major seismic discontinuities within the crust and upper mantle below the seismological stations. Аnalysis of the data revealed variations in the timing of the Ps phases, indicating heterogeneity in Moho depth across the region. Specifically, Ps phases were observed between 4,0 and 4,5 seconds after the incident P arrival at the seismological station Skopje (SKO), between 3,5 and 4,5 seconds at the seismological station Valandovo (VAY), and between 5,0 and 5,5 seconds at the Ohrid (OHR) seismological station. To determine the crustal structure, an inversion of the obtained receiver functions was performed using a linearized iterative technique to derive 1-D seismic velocity models of the crust. The inversion results reveal significant variations in crustal thickness, with Moho depths ranging from approximately 34–36 km beneath the Valandovo (VAY) seismological station in the east to over 42–44 km beneath the Ohrid (OHR) seismological station in the west. At the Skopje (SKO) seismological station, the Moho depth is around 36 km. These results provide new constraints on the lithospheric structure of our country and offer valuable insights into the complex tectonic framework of the region.
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References
[1] Arsovski, M. (1997): Tectonics of Macedonia. Faculty of Mining and Geology – Štip.
[2] Ammon, C. J., Randall, G. E., Zandt, G. (1990): On the non-uniquess of receiver function inversions. J. Geophys. Res., 95 (B10), 15303–15 318. doi:10.1029/JB095iB10p15303
[3] Ammon, C. J. (1991): The isolation of receiver effects from teleseimic P waveforms. Bull. Seism. Soc. Am., 81 (6), 2504–2510. https://doi.org/10.1785/BSSA0810062504
[4] Boykova, A. (1999): Moho discontinuity in central Balkan Peninsula in the light of the geostatical structural analysis. Physics of the Earth and Panetary Interiors, 114 (1–2), 49–58. https://doi.org/10.1016/S0031-9201(99)00045-X
[5] Delipetrov, T., Blažev, K., Doneva, B., Popovski, R. (2016): Map of the Moho discontinuity of the Republic of Macedonia. (III Congress of Geologists of Republic of Macedonia). Geologica Macedonica, 4 (2), 493–496. ISSN 0352-1206.
[6] Dragašević, T., Andrić. B. (1982): O ispitivanju građe Zemljine kore primenom metode dubokog seizmičkog sondiranja na području Jugoslavije. Zbornik radova Savjetovanja Jug. komiteta za geofiziku, Skopje.
[7] Herrmann, R. B. (2002): An Overview of Synthetic Seismogram Computation, Version 3.30.
[8] Herrmann, R. and Ammon, C. (2002): Computer Programs in Seismology, Vol VI, St Louis University, MO, USA.
[9] Herrmann, R. B., Ammon, C. J. (2004): Generic Seismic Application Coding, Version 3.30.
[10] Kennett, B. L. N., Engdahl, E. R., Buland R. (1995): Constraints on seismic velocities in the Earth from travel times. Geophys J Int. 122, 108–124. https://doi.org/10.1111/j.1365-246X.1995.tb03540.x
[11] Kind, R., Vinnik, L. P. (1988): The upper mantle discontinuities undermeath the GRF array from P-to-S converted phases, J. Geophys. 62 (1), 138–147. https://journal.geophysicsjournal.com/JofG/article/view/135
[12] Kosarev, G. L., Petersen, N. V., Vinnik, L. P., and Roecker, S. W. (1993): Receiver function for the Tien Shan analog broadband network: contrast in the evolution of structure across the Talasso-Fargana fault. J. Geophys. Res., 98, 4437–4448. https://doi.org/10.1029/92JB02651
[13] Langston, C. A. (1977): Corvallis, Oregon, crustal and upper mantle receiver structure from teleseismic P and S waves, Bulletin of the Seismological Society of America, 67 (3) 713–724. https://doi.org/10.1785/BSSA0670030713
[14] Langston, C. A. (1979): Structure under Mount Rainer, Washington, inferred from teleseismic body waves. J. Geophys. Res., 84, (B9) 4749–4762. https://doi.org/10.1029/JB084iB09p04749
[15] Ormeni, R. (2009): Crustal structures beneath the seismogenic zones and lateral velocity contrasts across deep faults of Albania. Journal of the Balkan Geophysical Society, Vol. 12, No. 1, pp. 1–8. https://doi.org/10.1029/JB084iB09p04749
[16] Owens, T. J., Zandt, G. and Taylor, S. R. (1984): Seismic evidence for an ancient rift beneath the Cumberland Plateau, Tennessee: A detailed analysis of broadband teleseismic P waveforms. J. Geophys. Res., 89 (B9) 7783–7795. https://doi.org/10.1029/JB089iB09p07783
[17] Papazachos, C. B. (1998): Crustal P- and S-velocity structure of the Serbomacedonian Massif (Northern Greece) obtained by nonlinear inversion of traveltimes, Geophys. J. Int. 134, 25–39. https://doi.org/10.1046/j.1365-246x.1998.00558.x
[18] Phinney, R. A. (1964): Structure of the Earth crust from spectral behavior of long-period body waves. J. Geophys. Res., 69, 2997–3017. https://doi.org/10.1029/JZ069i014p02997
[19] Projet PNUD-UNESCO: Pour I’etude de la seismicite de la region Balkanique. Tables des temps de propagation del ondes seismicite (hodochrones) pour la region des Balkans. Prep. l’Unesco par le Bur.Centr.Internat. de Seism, 1972.
[20] Vinnik, L. P. (1977): Detection of waves coverted from P to SV in the mantle, Phys. Earth Planet. Inter., 15 (1), 39–45. https://doi.org/10.1029/GL015i007p00669
