Syngenetic and Paleokarstic Copper Mineralization in the Palaeozoic Platform Sediments of West Central Sinai, Egypt
- John Parnell,
- Ye Lianjun and
- Chen Changming
Published Online: 3 APR 2009
Copyright © 1990 The International Association of Sedimentologists
Sediment-Hosted Mineral Deposits: Proceedings of a Symposium Held in Beijing, People's Republic of China, 30 July-4 August 1988
How to Cite
El Sharkawi, M. A., El Aref, M. M. and Abdel Motelib, A. (1990) Syngenetic and Paleokarstic Copper Mineralization in the Palaeozoic Platform Sediments of West Central Sinai, Egypt, in Sediment-Hosted Mineral Deposits: Proceedings of a Symposium Held in Beijing, People's Republic of China, 30 July-4 August 1988 (eds J. Parnell, Y. Lianjun and C. Changming), Blackwell Publishing Ltd., Oxford, UK. doi: 10.1002/9781444303872.ch13
Department of Geology, The Queen's University of Belfast, Belfast BT7 INN, UK
- Published Online: 3 APR 2009
- Published Print: 27 SEP 1990
Print ISBN: 9780632028818
Online ISBN: 9781444303872
- strata-bound to stratiform malachite;
- Cambro-Ordovician sediments;
- Malachite, occurring in Nasib Formation;
- Carboniferous karst profile;
- Um Bogma region
Copper in the form of carbonate, chloride, silicate, sulphate and phosphate minerals is encountered within the Palaeozoic sediments of the Um Bogma region, West Central Sinai, Egypt. They are classified into two contrasting genetic types: (1) strata-bound to stratiform malachite confined within a certain stratigraphic level of Cambro-Ordovician clastic sediments; and (2) strata-bound copper carbonate, chloride, silicate, sulphate and phosphate confined within a buried Carboniferous karst profile.
The geometric distribution patterns of the malachite of the first type represent a high degree of congruence with the primary, deformational and biogenic sedimentary structures of the enclosing rocks. The malachite was formed syngenetically during the accumulation of the host sediments in fluviodeltaic environments.
In the second type, the geometric distributions of the copper minerals and the chemistry and mineral composition of the host karst products reveal that these copper minerals are of pedogenic origin, deposited from solutions in a paleosol developed during the Carboniferous karst event. The variation in the pH and Eh conditions of the paleosol environment and the related biogenic processes are suggested to be the main factors controlling the leaching of the copper and its migration and redeposition within the subsoil and topsoil horizons of the paleokarst profile.