Skip to main content


One-dimensional P-wave velocity structure in the northern Red Sea area, deduced from travel time data

Article metrics

  • 244 Accesses

  • 3 Citations


Travel time inversion of local earthquake data was used to improve a one-dimensional (1-D) P-wave velocity structure model for the northern Red Sea area, including the entrance of the Gulf of Suez and the Gulf of Aqaba. The 1-D velocity model and station corrections were obtained by using 1538 P-arrivals from 216 well-located earthquakes recorded at ten local seismic stations from August 1994 to January 1999. Earthquakes used in the present study were located in depths less than 28 km so that the upper 20 km of the 1-D velocity model was well constrained. The resulting P-velocity model indicated velocities from 5.0 to 6.0 km/sec down to a depth of 10 km, and velocities from 6.0 to 6.8 km/sec with a nearly constant gradient in a depth range from 10 to 20 km. This 1-D velocity model reduced the RMS residual by 47% from 0.21 to 0.11 sec and improved routine earthquake locations, which clearly indicated clusters of hypocenters in the southern tip of the Sinai Peninsula and the entrance of the Gulf of Suez. The resulting station corrections suggested irregular surface geology in the area. Negative and positive station corrections were obtained; the minimum value (−0.35) was observed at the station MAZR, while the maximum value (0.24) at SHRM.


  1. Ambraseys, N. N., C. P. Melville, and R. D. Adams, The Seismicity of Egypt, Arabia and the Red Sea, 173 pp., Cambridge University Press, Cambridge, 1994.

  2. Avedik, F., L. Geli, J. M. Gaulier, and J. P. le Formal, Results from three refraction profiles in the Northern Red Sea (above 25°) recorded with Ocean Bottom Vertical Seismic array, Tectonophys., 153, 89–101, 1988.

  3. Barakat, H. and P. Miller, Geology and petroleum exploration, Safaga concession, North Red Sea, Egypt, 7th E.G.P.C., Cairo, March 1984, 24 pp., 1984.

  4. Bayer, H. J., H. Hotzl, A. R. Jado, B. Rocher, and W. Voggenreiter, Sedimentary and structural evolution of northwest Arabian Red Sea margin, Tectonophys., 153, 137–151, 1988.

  5. Ben-Menahem, A. and E. Aboodi, Tectonic pattern in the northern Red Sea region, J. Geophys. Res., 76, 2674–2689, 1971.

  6. Ben-Menahem, A., A. Nur, and M. Vered, Tectonics, seismicity and structure of the Afro-Eurasian junction—the breaking of an incoherent plate, Phys. Earth Planet. Inter., 12, 1–50, 1976.

  7. Colletta, A., P. Le Quellec, J. Letouzey, and I. Moretti, Longitudinal evolution of the Suez rift structure (Egypt), Tectonophys., 153, 221–233, 1988.

  8. Daggett, P., P. Morgan, F. K. Boulos, S. F. Hennin, A. A. El-Sherif, A. A. El-Sayed, N. Z. Basta, and Y. S. Melek, Seismicity and active tectonics of the Egyptian Red Sea margin and the northern Red Sea, Tectonophys., 125, 313–324, 1986.

  9. DeMets, C., R. G. Gordon, D. F. Argus, and S. Stein, Current plate motion, Geophys. J. Int., 101, 425–478, 1990.

  10. Ellsworth, W. L., Three dimensional structure of the crust and mantel beneath the island of Hawaii, Ph.D. thesis, Mass. Inst. of Technol., Cambridge, 1977.

  11. Gaulier, J. M., X. Le Pichon, N. Lyberis, F. Avedik, L. Geli, and I. Moretti, Seismic study of the crust of the northern Red Sea and Gulf of Suez, Tectonophys., 153, 55–88, 1988.

  12. Hosney, H. M., Geophysical investigation of the Gulf of Suez-Consequence for tectonic evolution of the Northern Red Sea, 188 pp., Diss., Univ. Kiel, 1985.

  13. Hurukawa, N., H. Murakami, N. Seto, I. Marzouk, A. Megahed, and E. Ibrahim, Establishment of the Seismological Telemetric Network at the southern part of the Gulf of Suez and the northern Red Sea, Second International Scientific Conference, Faculty of Science, Al-Azhar Univ., Cairo, Egypt, 17–20, March, 1997.

  14. Hurukawa, N., N. Seto, H. Inoue, K. Nishigami, I. Marzouk, A. Megahed, E. M. Ibrahim, H. Murakami, M. Nakamura, T. Haneda, S. Sugiyama, T. Ohkura, Y. Fujii, H. M. Hussein, A. S. Megahed, H. F. Mohammed, R. Abdel-Fattah, M. Mizoue, S. Hashimoto, M. Kobayasi, and D. Suetsugu, Seismological observation in and around the southern part of the Gulf of Suez in Egypt, Bull. Seismol. Soc. Amer., 2001 (in press).

  15. Kebeasy, R. M., The Geology of Egypt, edited by R. Said, pp. 51–95, A. A. Balkema, Rotterdam, Netherlands, 1990.

  16. Kissling, E., Geotomography with local earthquake data, Rev. Geophys., 26, 659–698, 1988.

  17. Kissling, E., Velest Users Guide, Internal report, Institute of Geophysics, ETH Zurich, 26 pp., 1995.

  18. Kissling, E., W. L. Ellsworth, D. Eberhart-Phillips, and U. Kradolfer, Initial reference model in seismic tomography, J. Geophys. Res., 99, 19635–19646, 1994.

  19. Lee, W. H. K., Realtime seismic data acquisition and processing, IASPEI Software Library, Vol. 1, 2nd ed., IASPEI, 1994.

  20. Lee, W. H. K. and J. C. Lahr, HYPO71: A computer program for determining hypocenter, magnitude, and first motion pattern of local earthquakes, U. S. Geol. Surv. Open File Rep., 75, 311, 1975.

  21. Lee, W. H. K., R. E. Bennett, and K. L. Meagher, A method of estimating magnitude of local earthquakes from signal duration, Geol. Surv. Open-File Rep., 28, 1972.

  22. Maamoun, M. E., Helwan seismic magnitude scale, Bull. Helwan Observatory, No. 196, 1978.

  23. Maamoun, M. and H. M. El Khashab, Seismic studies of the Shadwan (Red Sea) earthquake, Bull. Helwan Inst. Astr. and Geophys., No. 171, 1976.

  24. Makris, J., A. Allam, T. Moktar, A. Basahel, G. A. Dehghani, and M. Bazari, Crustal structure at the northwestern region of the Arabian shield and its transition to the Red Sea, Bull. Fac. Earth Sci., K. Abdulaziz Univ., 6, 435–447, 1983.

  25. Marzouk, I., Crustal structure of Egypt deduced from deep seismic and gravity data, Ph.D. thesis, 118 pp., Univ. of Hamburg, Germany, 1988.

  26. Mckenzie, D., D. Davies, and P. Molnar, Plate tectonics of the Red Sea and East Africa, Nature, 226, 243–248, 1970.

  27. Meshref, W. M., Tectonic framework of Egypt, in The Geology of Egypt, edited by R. Said, pp. 113–155, A. A. Balkema, Rotterdam, Netherlands, 1990.

  28. Pavlis, G. L. and J. R. Booker, A study of the importance on nonlinearity in the inversion of earthquake arrival time data for velocity structure, J. Geophys. Res., 88, 5047–5055, 1983.

  29. Roecker, S. W., Seismicity and tectonics of the Pamir-Hindu Kush region of central Asia, Ph.D. thesis, Mass. Inst. of Technol., Cambridge, 1981.

  30. Said, R., The Geology of Egypt, Elsevier, Amsterdam, 377 pp., 1962.

  31. Salamon, A., A. Hofstetter, Z. Garfunkel, and H. Ron, Seismicity of eastern Mediterranean region: Perspective from the Sinai subplate, Tectonophys., 263, 293–305, 1996.

  32. Steckler, M. S., F. Berthelot, N. Lyberis, and X. Le Pichon, Subsidence in the Gulf of Suez: implications for rifting and plate kinematics, Tectonophys., 153, 249–270, 1988.

  33. Tewfik, N. and M. Ayyad, Petroleum exploration in the Red Sea Shelf of Egypt, 6th E.G.P.C, Cairo, March 1982, 30 pp., 1982.

  34. Thurber, C. H., Nonlinear earthquake location: Theory and examples, Bull. Seismol. Soc. Amer., 75, 779–790, 1985.

  35. Thurber, C. H., Hypocenter velocity structure coupling in local earthquake tomography, Phys. Earth Planet. Inter., 75, 55–62, 1992.

  36. Tramontini, C. and D. Davies, A seismic refraction survey in the Red Sea, Geophys. J. R. Astron. Soc., 17, 2225–2241, 1969.

  37. Vincent, C., A. Rolando, and T. Paul, The Sinai triple junction revisited, Tectonophys., 141, 181–190, 1987.

Download references

Author information

Correspondence to Hesham Mohamed.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Mohamed, H., Miyashita, K. One-dimensional P-wave velocity structure in the northern Red Sea area, deduced from travel time data. Earth Planet Sp 53, 695–702 (2001) doi:10.1186/BF03352397

Download citation


  • Velocity Model
  • Station Correction
  • Moho Depth
  • Arabian Plate
  • Sinai Peninsula