Abstract
A zircon study has been made on eleven samples of igneous rocks from the Saudi Arabian Craton. Ages of sized and magnetic fractions of zircon concentrates show variable degrees of discordance which seem to result from a very young disturbance that produces linear arrays in the Concordia plot. Model age calculations based on a statistically and geologically reasonable lower intercept produce very consistent internal relationships. The Pan African Orogeny, considered to be responsible for loss of radiogenic argon and strontium from minerals of many rocks, does not appear to have affected the zircon data, even though uplift had exposed the rocks of the Arabian Shield at that time.
Tonalite, granodiorite, and crosscutting leucoadamellite bodies in the southern part of the An Nimas Bathylith yield ages in the time range 820−760 Ma. A narrow time range of 660 to 665 million years was indicated for ages of widely separated and compositionally different intrusive bodies all to the east of the An Nimas Bathylith. This work suggests that the younger end of the age spectrum established from regional K-Ar and Rb-Sr measurements may be underestimated, and that magmatic activity could be more episodic than previously assumed.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Aldrich, L.T.: Geochronologic data for the Arabian Shield; Section 1 — Radiometric age determinations of some rocks from the Arabian Shield. U.S. Geol. Survey Saudi Arabian Project Report 240. (1978)
Anderson, R.E.: Geology of the Wadi Atf and Mayzola quadrangles, Kingdom of Saudi Arabia: Saudi Arabian Directorate Gen. Mineral Resources Geol. Map, scale 1∶100,000 (1978)
Brown, G.F.: Tectonic map of the Arabian Peninsula. Saudi Arabian Dir. Gen. Mineral Research Geol. Map AP 2, scale 1∶4,000,000 (1972)
Brown, G.F., Coleman, R.G.: The tectonic framework of the Arabian Peninsula. International Geol. Congress, 24th session, pt. 3, 300–305 (1972)
Brown, G.F., Hedge, C., Marvin, R.: Geochronological data for the Arabian Shield. Section 2 — Tabulation of Rb-Sr and K-Ar ages given by rocks of the Arabian Shield. U.S. Geol. Survey Saudi Arabian Project Report 240 (1978)
Brown, G.F., Jackson, R.O.: Geology of the Tihamat Ash Sham quadrangle, Kingdom of Saudi Arabia. U. S. Geol. Survey Misc. Geol. Inv. Map I-216A, scale 1∶500,000 (1958)
Brown, G.F., Jackson, R.O.: Geology of the Asir quadrangle, Kingdom of Saudi Arabia. U. S. Geol. Survey Misc. Geol. Inv. Map I-217A, scale 1∶500,000 (1959)
Brown, G.F., Jackson, R.O.: The Arabian Shield. International Geol. Congress 21st session, pt. 9, 69–77 (1960)
Brown, G.F., Jackson, R.O., Bogue, R.G., McLean, W.H.: Geologic map of the Southern Hijaz quadrangle, Kingdom of Saudi Arabia. U. S. Geol. Survey Misc. Geol. Inv. Map I–210, scale 1∶500,000 (1962)
Cameron, A.E., Smith, D.H., Walker, R.L.: Mass spectrometry of nanogram size samples of lead. Anal. Chem.41, 525–526 (1969)
Clifford, T.N.: The structural framework of Arabia. In: African magmatism and tectonics. (T.N. Clifford and I.G. Gass, eds.) Connecticut: Hafner Publishing Co. (1970)
Coleman, R.G., Brown, G.F., Keith, T.E.C.: Layered gabbros in southwest Saudi Arabia. U.S. Geol. Survey Prof. Paper800-D, 143–150 (1972)
Coleman, R.G., Ghent, E.D., Fleck, R.J., Griscom, A.: The Jabal Shayi layered gabbro in southwestern Saudi Arabia. U.S. Geol. Survey Saudi Arabian Project Open File Report159, 93 p. (1973)
Cumming, G.L.: A re-calculation of the age of the solar system. Can. J. Earth Sci.6, 719–735 (1969)
Fleck, R.J., Coleman, R.G., Cornwall, H.R., Greenwood, W.R., Hadley, D.G., Schmidt, D.L., Prinz, W.C., Ratte, J.C.: Geochronology of the Arabian Shield, western Saudi Arabia: K-Ar results. Geol. Soc. Am. Bull.87, 9–21 (1976)
Fleck, R.J., Greenwood, W.R., Hadley, D.G., Anderson, R.E., Schmidt, D.L.: Age and evolution of the southern part of the Arabian Shield. U.S. Geol. Surv. Prof. Paper (in press, 1979)
Fleck, R.J., Greenwood, W.R., Hadley, D.G., Prinz, W.C.: Age and origin of tonalite-granodiorite gneiss, western Saudi Arabia (abstr.). Eos Trans. Am. Geophys. Union54, 1226 (1973)
Gass, I.G.: Tectonic and magmatic evolution of the Afro-Arabian Dome. In: African Magmatism and Tectonics (T.N. Clifford and I.G. Gass, eds.). pp. 285–300. Connecticut: Halfner Publishing Co. 1970
Goldich, S.S., Mudrey, M.G.: Dilatancy model for discordant UPb zircon ages. In: Recent Contributions to Geochemistry and Analytical Chemistry (A.I. Tugarinov, ed.) pp. 466–470. New York: John Wiley and Sons, 1972
Greenwood, W.R., Hadley, D.G., Anderson, R.E., Fleck, R.J., Schmidt, D.L.: Proterozoic cratonization in southwestern Saudi Arabia. Phil. Trans. Roy. Soc. London, Ser. A280, 517–527 (1976)
Greenwood, W.R., Roberts, R.J., Bagdady, A.: Mineral belts in western Saudi Arabia. U.S. Geol. Survey Saudi Arabian Project Report177, p. 26 (1963)
Hadley, D.G.: Geology of the Wadi Hali quadrangle, Sheet 18/41 B, Kingdom of Saudi Arabia. Geologic map GM-21, scale 1∶100,000 (1975)
Hadley, D.G., Schmidt, D.L.: Nonglacial origin for conglomerate beds in the Wajid Sandstone of Saudi Arabia. U.S. Geol. Survey Saudi Arabian Project Open File Report 174, p. 27 (1974)
Jackson, R.O., Bogue, R.G., Brown, G.F., Gierhart, R.D.: Geologic map of the southern Najd quadrangle, Kingdom of Saudi Arabia. U.S. Geol. Survey Misc. Geol. Inv. Map 1–211 A, scale 1∶500,000 (1963)
Krough, T.E.: A low contamination method for hydrothermal decomposition of zircon and extraction of U and Pb for isotopic age determination. Geochim. Cosmochim. Acta37, 485–494 (1973)
Nicolaysen, L.O.: Solid diffusion in radioactive minerals and the measurements of absolute age. Geochim. Cosmochim. Acta11, 51–59 (1957)
Page, R.W.: Response of U-Pb zircon and Rb-Sr total rock systems to low grade regional metamorphism in Proterozoic igneous rocks, Mt. Isa, Australia. An Rp. Geophys. Lab. Carn. Inst. Wash., No. 1700, 813–821 (1976)
Page, R.W.: Response of Ub-Pb zircon and Rb-Sr total-rock and mineral systems to low-grade regional metamorphism in proterozoic igneous rocks, Mount Isa, Australia. J. Geol. Soc. Australia25, 141–164 (1978)
Prinz, W.C.: Reconnaissance Geology of the Jabal 'Aja quadrangle, sheet 18/42A, Kingdom of Saudi Arabia. Geol. Map GM-17, scale 1∶100,000 (1975)
Schmidt, D.L., Hadley, D.G., Greenwood, W.R., Gonzales, L., Coleman, R.G., Brown, G.R.: Stratigraphy and tectonism of the southern part of the Precambrian Shield of Saudi Arabia. Saudi Arabian Dir. Gen. Mineral Research Bull.8, p. 13 (1973)
Steiger, R.H., Jager, E.: Subcommission on Geochronology: Convention on the use of decay constants in geo- and cosmo-chronology. Earth Planet. Sci. Lett.36, 359–362 (1977)
Stern, T.W., Goldich, S.S., Newell, M.F.: Effects of weathering on the U-Pb ages of zircon from the Morton Gneiss, Minnesota. Earth Planet. Sci. Lett.1, 369–371 (1969)
Tilton, G.R.: Volume diffusion as a mechanism for discordant lead ages. J. Geophys. Res.65, 2933–2945 (1960)
Wasserburg, G.J.: Diffusion processes in lead-uranium systems. J. Geophys. Res.68, 4823–4846 (1963)
York, D.: Least squares fitting of a straight line with correlated errors. Earth Planet. Sci. Lett.5, 320–324 (1969)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Cooper, J.A., Stacey, J.S., Stoeser, D.G. et al. An evaluation of the zircon method of isotopic dating in the Southern Arabian Craton. Contr. Mineral. and Petrol. 68, 429–439 (1979). https://doi.org/10.1007/BF01164527
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01164527