Abstract
The territory of Morocco has been used to test a model of block structure of the lithospere, in which block boundaries guide magmatism and predetermine the most favorable places for the concentration of metals. The examination of Van den Bosch’s (1971, 1981) isostatic gravity anomaly map has revealed such a block structure, with boundaries trending north-south and east-west. In Triassic and Jurassic time, these boundaries controlled, to some degree, the shape of a subsiding depression or trough, which is now reflected in the course of the High Atlas Mts. and in the changes in strike of the South Atlas fault zone.
One of the deep-seated N-S trending boundaries, following a longitude close to 7° W, extends farther south toward the northern border of the West African craton. A major concentration of gabbro-dolerite rocks of early Mesozoic age occurs near the intersection of the above N-S boundary, with an E-W trending one in the Saharan part of the Anti-Atlas, south of Foum Zguid.
Quantitative chemical analyses have revealed five differentiates of a basic magma, with two distinct types of dolerite as the prevailing rock type. Significant similarities have been found between the composition of Type-1 and Type-2 dolerite from Foum Zguid, and the “Upper contact dolerites” of the Noril’sk-Talnakh region in Siberia, USSR.
In the SW-part of the Foum Zguid region, the process of magmatic differentiation led to a highly differentiated intrusive, over which a potassic metasomatism has been superimposed. The intrusive contains “schlieren” with pyrrhotite and pentlandite, the latter containing 2–3% Co. The contact zone of the intrusive, consisting of a serpentinized limestone and hornfels, is very rich in titanium and contains a fine dissemination of a sulfide containing about 38% Ni, 17% Fe and 6% Co. The observations indicate that magmatic differentiation in the SW parts of the Foum Zguid region has reached a stage in which separation and concentration of nickel and cobalt was possible.
It is suggested that a differentiated body of gabbroic rocks with more substantial concentrations of Ni, Co and possibly Pt-group metals may occur beneath the “screen” of dolerites in the SW-parts of the Foum Zguid region, similar to that described from beneath a “screen” of the “Upper contact dolerites” of the Noril’sk-Talnakh region near the western border of the Siberian platform (Vilensky et al., in Smirnov, 1976).
This is a preview of subscription content, log in via an institution.
Buying options
Tax calculation will be finalised at checkout
Purchases are for personal use only
Learn about institutional subscriptionsPreview
Unable to display preview. Download preview PDF.
References
Bensaid, M., J. Kutina, A. Mahmood and M. Saadi, 1985, ‘Structural evolution of Morocco and new ideas on basement controls of mineralization.’ Global Tectonics and Metallogeny. v. 3, p. 59–69.
Bensaid, M., and A. Mahmood, 1987, ‘The use of Landsat imagery in structural studies of Middle Morocco.’ COSPAR conference, Toulouse, France, Proceedings. Advances in Space Research, v. 7, no. 3, p. 87–94.
Bonatti, E., 1971, ‘Ancient continental mantle beneath oceanic ridges.’ Journal of Geophysical Research, v. 76, p. 3825–3831.
Bonatti, E., 1973, ‘Origin of offsets of the Mid-Atlantic Ridge in fracture zones.’ Journal of Geology, v. 81, p. 144–156.
Bonatti, E. and J. Honnorez, 1971, ‘Nonspreading crustal blocks at the Mid-Atlantic Ridge.’ Science, v. 174, p. 1329–1331.
Carte Géologique de 1’Anti-Atlas Central et de la zone synclinal de Ouarzazate. Feuilles Ouarzazate, Alougoum et Telouet Sud. Scale 1:200,000. Published by Service Géologique du Maroc, Notes et Mémoires No. 138, 1970.
Carte Géologique des Plaines du Dra au Sud de l’Anti-Atlas Central. Agadir Tissinnt — Oued Zemoul. Published by Service Géologique du Maroc, Notes et Mémoires No. 219, 1971.
Carte des Gîtes Minéraux du Maroc. Scale 1:500,000. Ministère de l’Energie et des Mines, Direction de la Géologie, Rabat, Morocco. (Unpublished edition)
Carte Géologique du Maroc, Scale 1:1,000,000. Published by Service Géologique du Maroc, Notes et Mémoires No. 260, 1985.
Demnati, A., 1979, Carte Magnétique du Maroc. Interpretation du leve aeromagnétique. Scale 1:1,000,000. Sheet Marrakech. Published by Service Géologique du Maroc, Notes et Mémoires No. 320C.
Dodin, D.A., B.N. Batuev, G.A. Mitenkov and V.M. Izoitko, 1971, ‘Atlas of the rocks and ores of the Noril’sk copper-nickel deposits.’ (In Russian) Leningrad, publ. by Nedra, 560 p.
Favorskaya, M.A. and I.N. Tomson, 1974, ‘Interrelation between the ore-concentrating lineaments of Eurasia and the Tethys belt’ (In Russian) 4th IAGOD Symposium, Varna, Bulgaria. Abstracts, p. 337–338.
Favorskaya, M.A., I.K. Volchanskaya, E.N. Sapozhinkova, N.V. Vinogradov, A.M. Kurchavov, V.A. Baskina and N.L. Shilin, 1985, ‘Tectonics, magmatism and mineralization of deep-seated zones of fracturing.’ (transi, of ‘skvoznye sistemy narushenii’), (In Russian) Moscow, publ. by Nauka, 168 p.
Géologie des Gîtes Minéraux Marocains, Tom I, 1980, Notes et Mémoires No. 276, Service Géologique du Maroc.
Gottfried, D. and A.J. Froelich, 1988, ‘Variations of palladium and platinum contents and ratios in selected early Mesozoic tholeiitic rock associations in the Eastern United States.’ U.S. Geological Survey Bulletin No. 1776, p. 332–341.
Gottfried, D., P.J. Aruscavage and N. Rait, 1988, ‘Fractionation of palladium and platinum in a Mesozoic diabase sheet, Gettysburg, PA.’ V.M.
Goldschmidt Conference, Program and Abstracts, Baltimore, Maryland (organized by the Geochemical Society), p. 44.
Gottfried, D., A.J. Froelich, N. Rait and P.J. Aruscavage, 1989, ‘Fractionation of paladium and platinum in a Mesozoic diabase sheet, Gettysburg basin, Pennsylvania: Implications for mineral exploration.’ Journal of Geochemical Exploration, in press.
Hildenbrand, T.G., R.P. Kucks, M.F. Hamouda and A. Bellot, 1988, Bouguer gravity map and related filtered anomaly maps of Morocco. In: M. Bensaid and J. Kutina, Final Report on AID-funded Project ‘Block Structure of the Lithosphere and its Role in the Genesis and Distribution of Metallic Ore Deposits.’ Rabat. Sept. 3, 1988, p. 77–93.
Kozlovsky, Ye.A., 1986, ‘Perspectives of a complex study of the Earth’s interior for a period until the year 2000 (In Russian).’ Soviet Geology, v. 1986, no. 12, p. 3–13.
Kutina J., 1980, ‘Jasperoid Peaks, Nevada.’ Progress Report prepared for W.A. Bowes, Inc., Steamboat Springs, Colorado. (Unpublished)
Kutina J., 1981, ‘Concentration of uranium in areas where the Appalachian folded belt is intersected by major east-west trending fracture zones.’ Global Tectonics and Metallogeny, v. 1, p. 254–275.
Kutina J., 1983, ‘Global tectonics and metallogeny: deep roots of some ore controlling fracture zones. A possible relation to small-scale convective cells at the base of the lithosphere?’ In:Advances in Space Research, v. 3, no. 2, p. 201–214, Pergamon Press.
Kutina, J. and G. Fabbri, 1972, ‘Relationship of structural lineaments and mineral occurrences in the Abitibi area of the Canadian Shield.’ Geological Survey of Canada Paper No. 71–9, 36 p.
Leblanc, M., 1981, ‘Ophiolites Précambriennes et gîtes arséniés de cobalt (Bou Azzer — Maroc).’ Published by Service Géologique du Maroc, Notes et Mémoires No. 280, 306 p.
Leblanc, M., 1983, ‘Metallogenesis of the Pan-African domain of the Anti-Atlas of Morocco.’ Bulletin of the Faculty of Earth Sciences, King Abdulaziz University, v. 6, p. 603–609, Jeddah, Saudi Arabia.
Lightfoot, P.C., AJ.. Naldrett, N.S. Gorbachev, W. Doherty and V.A. Fedorenko, 1989, ‘Recent geochemical data from Noril’sk, USSR — The relative roles of the mantle and crust in the genesis of the Siberian traps and mineralized and unmineralized intrusions.’ Abstract of a paper presented at the IAGOD workshop on “The Role of the Upper Mantle in Metallogeny” at the 28th IGC, Washington, D.C. (To be published in Global Tectonics and Metallogeny).
Michard, A., 1976, ‘Eléments de Géologie Marocaine.’ Published by Service Géologique du Maroc, Notes et Mémoires No. 252, 408 p.
Montaser, A. and D.W. Golightly, 1987, ‘Inductively coupled plasmas in analytical atomic spectrometry.’ VCH Publishers, Inc., New York. 590 p.
Saadi, M., 1971, ‘Relationship between structural alignments associated with Hercynian dolerite dykes and copper deposits in Morocco.’ Mining Geological Society of Japan, Special Issue 3, p. 115–121.
Saadi, M., 1980, ‘Le Maroc géotectonique et son evolution structurale et gîologique.’ Ministère de l’Energie et des Mines, Direction de la Géologie, Rapport Service Géologique Maroc. No. 1104, 187 p.
Saadi, M., 1982a, Carte structurale du Maroc, 1:2,000,000. Published by Service Géologique du Maroc, Notes et Mémoires No. 278, And: ‘Reseau d’alignements structuraux du Maroc’ (printed on the reverse side of the Carte structurale).
Saadi, M., 1982b, Carte minière et energetique du Maroc, 1:2,000,000. Published by Service Géologique du Maroc, Notes et Mémoires. No. 279.
Saadi, M. and A. Mahmood, 1984, ‘Lineaments in Morocco and their relationship with some ore deposit occurrences.’ Global Tectonics and Metallogeny, v. 2, p. 195–211.
Skinner, N.G., F.W. Brown and F.J. Flanagan, 1981, ‘The H2O+ contents of some geochemical standards predicted by a calibration line.’ Geostandards Newsletter, v. 5, no. 1, p. 3–11.
Smirnov, V.L., ed. 1976, ‘Geology of Mineral Deposits.’ English translation, Mir Publishers, Moscow, 520 p.
Van den Bosch, J.W.H., 1971, Carte gravimetrique du Maroc au 1:500,000. Published by Service Géologique du Maroc, Notes et Mémoires No. 234.
Van den Bosch, J.W.H., 1981, Mémoire explicatif de la carte gravimetrique du Maroc (provinces du Nord) au 1:500,000. Published by Service Géologique du Maroc, Notes et Mémoires No. 234 bis, 220 p.
Zolotukhin, V.V., 1982, ‘On the process of magma differentiation in certain intrusives of the Noril’sk type.’ Geologiya i Geofizika, v. 23, no. 6, p. 54–63. (English translation in Soviet Geology and Geophysics, Allerton Press, Inc.)
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1992 Springer Science+Business Media Dordrecht
About this paper
Cite this paper
Kutina, J. et al. (1992). The Gabbro-Dolerite Magmatism of the Foum Zguid Region: Relation to Deep Structure of Morocco and Possible Potential for Cobalt, Nickel and Platinum-Group Metals. In: Mason, R. (eds) Basement Tectonics 7. Proceedings of the International Conferences on Basement Tectonics, vol 1. Springer, Dordrecht. https://doi.org/10.1007/978-94-017-0833-3_13
Download citation
DOI: https://doi.org/10.1007/978-94-017-0833-3_13
Publisher Name: Springer, Dordrecht
Print ISBN: 978-90-481-4117-3
Online ISBN: 978-94-017-0833-3
eBook Packages: Springer Book Archive