Zusammenfassung
Die Grundgebirgsschwelle zwischen Gebel Uweinat und Bir Safsaf (Western Desert/ Ägypten) war während des Präkambriums durch vier Episoden von Deformation, Metamorphose und Anatexis gekennzeichnet. Die endgültige Kratonisierung erfolgte im Jungproterozoikum im Verlauf eines Pan-Afrikanischen Thermalereignisses. Die während des Jungproterozoikums als Folge großräumiger Intraplattentektonik entstandenen Bruchsysteme wurden während des Phanerozoikums periodisch reaktiviert. Die Platznahme anorogener Magmen erfolgte in mindestens sechs verschiedenen Zeiträumen hauptsächlich entlang dieser Bruchstrukturen.
Abstract
The Uweinat — Bir Safsaf Uplift, Western Desert/Egypt, four episodes of deformation and related metamorphism and anatexis occurred until the final cratonisation during the Late Pan-African event was completed. From that time on, probably six independent (Table 4) magmatic episodes can be recognized up to the Quaternary. This anorogenic type of magmatism is mainly related to a fracture system which originated in the Late Precambrian as a result of intraplate block faulting. Periodical reactivation of these older fracture zones throughout the Phanerozoic gave way to the different types of plutonic and volcanic rock assemblages.
Résumé
Le massif soulevé compris entre le Gebel Uweinat et Bir Safsaf, dans le Désert occidental de l'Egypte, a été le siège de 4 épisodes de déformations avec métamorphisme et anatexie jusqu'à sa cratonisation finale au cours de la Phase Pan-africaine tardive. A partir de ce moment, probablement six épisodes magmatiques indépendants peuvent être reconnus jusqu'au Quaternaire. Ce type anorogénique de magmatisme est principalement en relation avec un système de fractures qui a pris naissance au Précambrien supérieur comme le résultat d'une régime de fracturation intraplaque. La réactivation périodique des ces zones de fractures anciennes durant le Phanérozoïque a conduit à la formation de ces différents types d'associations de roches volcaniques et plutoniques.
Краткое
содержание Порог основных гор ме жду Gebei Uweinat и Bir Safsaf (западная пус тыня. Египет) претерпел во время до кембрия 4 деформации, сопровождающиеся ме таморфизмом и анатексисом. Окончат ельная кратонизация произошла только в позднем прот ерозое в течение некого панаф риканского термичес кого события. Возникшая во время по зднего протерозоя система р азломов, как следстви е крупномасштабной ме жплитовой тектоники, претерпела реактиви рование во время фане розоя. В образовавшихся в эти х структурах разломах скопились м агмы. Причем такое зам ещение происходило, по-крайн ей мере, шесть раз.
Article PDF
Avoid common mistakes on your manuscript.
References
Almond, D. C.: Younger granite complexes of Sudan. In: Al-Shanty, A. M. S. (Ed.), Evolution and Mineralization of the Arabian-Nubian shield,14, 151–164, Pergamon Press, Oxford, 1979.
Briden, J. C., Morris, W. A. &Piper, J. D. A.: Regional and global implications. In: Paleomagnetic studies in the British Caledonides - Geophys. J. R. astr. Soc.34, 107–134, 1973.
Brooks, C., Hart, S. R. &Wendt, I.: Realistic use of two-error regression treatments as applied to rubidium-strontium data - Rev. Geophys. Space Phys.,10, 551–577, 1972.
Cahen, L., Snelling, N. J., Delhal, J. &Vail, J. R. (with the collaboration ofBonhomme, M. &Ledent, D.): The geochronology and evolution of Africa - Clarendon Press, Oxford, 1983.
Fay, M. &Herrmann-Degen, W.: Mineralogy of Campanian/Maastrichtian sand deposits and a model of basin development for the Nubian group of the Dakhla basin (SW-Egypt), (in prep.).
Hunting Geology &Geophysics Ltd.: Geology of the Jabal Al Uwaynat area, Libyan Arab Republic - Unpublished Rep., Industrial Research Centre, Department of Geological Research and Mining, Tripoli, Libya, 1974.
Karche, J.-P. &Vachette, M.: Migration des complexes subvolcaniques à structure annulaire du Niger. Conséquences - C. R. Acad. Sc. Paris,282, Série D, 2033–2036, 1976.
Klerkx, J. &Rundle, C. C.: Preliminary K/Ar results on different igneous rock formations from the Jebel Uweinat region (S. E. Libya) - Mus. Roy. Afr. centr., Tervuren (Belg.), Dépt. Géol. Min., Rapp. ann. 1975, 104–111, 1976.
—: &Deutsch, S.: Résultats préliminaires obtenus par la méthode Rb/Sr sur l'age des formations precambriennes de la région d'Uweinat (Libya) - Mus. roy. Afr. centr., Ter- vuren (Belg.), Dépt. Géol. Min., Rapp. ann. 1976, 83–94, 1977.
-: Age and metamorphic evolution of the Basement complex around Jabal al Awaynat — In: Salem, M. J. and Busrewil, M. T. (Ed.), The geology of Libya,3, 901–906, 1980.
Klitzsch, E., Harms, J., Lejal-Nicol, A. List, F.: Major subdivisions and depositional environments of Nubian strata, SW Egypt - Am. Ass. Petrol. Geol. Bull.,63, No. 6, 967–974, 1979.
Kröner, A.,Stern, R. J.,Fleck, R. J.: Chronology and mechanism of Pan-African crustal accretion in northeast Africa and Arabia - Abstracts, 12th Coll. Afr. Geology, April 1983, Brussels, p. 55, 1983.
Marholz, W. W.: Geological exploration of the Kufra region, April–May, 1965. Bull. Geol. Surv. Libya,8, 76 pp., 1968.
Ries, A. C.: Geochronology and tectonic evolution of the Late Proterozoic of NE-Africa - Abstracts, 12th Coll. Afr. Geology, April 1983, Brussels, p. 84, 1983.
Rogers, J. J. W., Ghuma, M. A., Nagy, R. M., Greenberg, J. K., Fullagar, P. D.: Plutonism in Pan-African belts and the geologic evolution of northeastern Africa - Earth and Planetary Science Letters,39, 109–177, 1978.
Schandelmeier, H.,Richter, A.Franz, G. (in press): Outline of the Geology of magmatic and metamorphic units from Gebel Uweinat to Bir Safsaf (SW-Egypt/NW-Sudan) - Journal Afr. Earth Sciences.
Steiger, R. H. &Jäger, E.: Subcommission on Geochronology: Convention on the Use of Decay Constants in Geo- and Cosmochronology - Earth and Planet. Sci. Lett.,36, 359–362, 1977.
Thorweihe, U.,Sonntag, C.,Klitzsch, E. (in press): Fossil groundwater reservoirs in the Eastern Sahara: Case-history of the Dakhla basin, Egypt.
York, D.: Least squares fitting of a straight line - Can. J. Phys.,44, 1079–1086, 1966.
—: Least squares fitting of a straight line with correlated errors - Earth Planet. Sci. Letters,5, 320–324, 1969.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Schandelmeier, H., Darbyshire, F. Metamorphic an magmatic events in the Uweinat — Bir Safsaf Uplift (Western Desert/Egypt). Geol Rundsch 73, 819–831 (1984). https://doi.org/10.1007/BF01824984
Issue Date:
DOI: https://doi.org/10.1007/BF01824984