Economic and Environmental Geology (자원환경지질)

The Korean Society of Economic and Environmental Geology (대한자원환경지질학회)
권호 표지
DOI QR코드

DOI QR Code

Application of Multivariate Statistics and Geostatistical Techniques to Identify the Distribution Modes of the Co, Ni, As and Au-Ag ore in the Bou Azzer-East Deposits (Central Anti-Atlas Morocco)

  • Souiri, Muhammad (Moulay Ismail University, Faculty of Science, Department of Geology) ;
  • Aissa, Mohamed (Moulay Ismail University, Faculty of Science, Department of Geology) ;
  • Gois, Joaquim (Faculty of Engineering, University of Porto) ;
  • Oulgour, Rachid (Moulay Ismail University, Faculty of Science, Department of Geology) ;
  • Mezougane, Hafid (Moulay Ismail University, Faculty of Science, Department of Geology) ;
  • El Azmi, Mohammed (Moulay Ismail University, Faculty of Science, Department of Geology) ;
  • Moussaid, Azizi (Moulay Ismail University, Faculty of Science, Department of Geology)
  • Received : 2020.06.19
  • Accepted : 2020.07.24
  • Published : 2020.08.28
Download PDF
⟨ Previous Next ⟩

Abstract

The polymetallic Co, Ni, Cu, As, Au, and Ag deposits of Bou Azzer East are located in the western part of the Bou Azzer inlier in the Central Anti Atlas, Morocco. Six stages of emplacement of the mineralization have been identified. Precious metals (native gold and electrum) are present in all stages of this deposit except the early nickeliferous stage. From the Statistical analysis of the Co, As, Ni, Au, and Ag contents of a set of 501 samples, shows that the Pearson correlation coefficient between As-Co elements (0.966) is the highest followed by that of the Au-Ag couple (0.506). Principal component analysis (PCA) and hierarchical ascending classification (HAC) of the grades show, that Ni is associated with the pair (As-Co) and Cu is rather related to the pair (Au-Ag). The kriging maps show that the highest values of the Co, As and Ni appear in the contact of the serpentinite with other facies, as for those of Au and Ag, in addition to anomalous zones concordant with those of Co, Ni and As, they show anomalies at the extreme South and North of the study area. The development of the anomalous Au and Ag zones is mainly along the N40-50°E and N145°E directions.

Keywords

References

  1. Admou, H., Fekkak, A., Razin, P., Egal, E., Youbi, N., Soulaimani, A., Blein, O., Baudin, T., Chevremont and ANZAR-Conseil. (2013) Carte geologique du Maroc (1:50,000), feuille Ait Ahmane. Notes et Memoires Service Geologique du Maroc., n.533, 142p.
  2. Ahmed, A.H., Arai, S. and Ikenne, M. (2009a) Mineralogy and paragenesis of the Co-Ni arsenide ores of Bou Azzer, Anti-Atlas, Morocco. Economic Geology., v.104, p.249-266. https://doi.org/10.2113/gsecongeo.104.2.249
  3. Ait Lahna, A., Tassinari, C.G.C., Youbi, N., Admou, H., Mata, J., Bouougri, H., Latifa, C, Ernst, R.E., Boumehdi, M.A., Maacha, L., Bodinier, J.L., El Messbahi, H., Ikenne, M., Bensalah, M. and Aarab, M. (2016) U-Pb Geochronology of the Taghdout Sill (Zenaga inlier, Anti-Atlas, Morocco): Refining the stratigraphy of the Taghdout Group. Proceedings of the: Resources and Innovative Geology - RIG2016. Montpellier, France, p.31.
  4. Blein, O., Baudin, T., Chevremont, P., Soulaimani, A., Admou, H., Gasquet, P., Cocherie, A., Egal, E., Youbi, N., Razin, P., Gombert, P. and Bouabdelli, M. (2014a) Geochronological constraints on the polycyclic magmatism in the Bou Azzer-El Graara inlier (central Anti- Atlas Morocco). Journal of African Earth Sciences, v.99, p.287-306. https://doi.org/10.1016/j.jafrearsci.2014.04.021
  5. Blein, O., Baudin, T., Soulaimani, A., Cocherie, A., Ch evremont, P., Admou, H., Ouanaimi, H., Hafid, A., Razin, P., Bouabdelli, M. and Roger, J. (2014b) New geochemical, geochronological and structural constraints on the Ediacaran evolution of the south Sirwa, Agadir-Melloul and Iguerda inliers, Anti-Atlas, Morocco. Journal of Africain. Earth Sciences, v.98, p.47-71. https://doi.org/10.1016/j.jafrearsci.2014.06.019
  6. Bodinier, J.L., Dupuy, C. and Dostal, J. (1984) Geochemistry of precambrian ophiolites from Bou Azzer, Morocco. Contributions to Mineralogy and Petrology, v.87, p.43-50. https://doi.org/10.1007/BF00371401
  7. Bouabdellah, M., Maacha, L., Levresse, G. and Saddiqi, O. (2016) The Bou Azzer Co-Ni-Fe-As ($\pm$ Au, $\pm$ Ag) district of Central Anti-Atlas (Morocco): A long-lived late Hercynian to Triassic magmatic-hydrothermal to lowsulphidation epithermal system. In: Bouabdellah M and Slack JF (eds), Mineral Deposits of North Africa, Mineral Resource Reviews, Springer International Publishing, Switzerland, p.229-247.
  8. Bouougri, E.H. and Saquaque, A. (2004) Lithostratigraphic framework and correlation of the Neoproterozoic northern West African Craton passive margin sequence (Siroua- Zenaga-Bouazzer Elgraara Inliers, Central Anti-Atlas, Morocco): an integrated approach. Journal of African Earth Sciences, v.39, p.227-238. https://doi.org/10.1016/j.jafrearsci.2004.07.045
  9. Chevremont, P., Belin, O., Razin, P., Baudin. T,. Barbanson, L., Gasquet, D., Soulaimani, A., Admou, H., Youbi, N., Bouabdelli, M. and anzar-conseil. (2013) Notice explicative, carte geologique de. Maroc (1:50,000). Feuille Bou Azzer Notes et Memoires Service. Geologique. n.535 bis, 153p.
  10. Clauer, N. (1974) Utilisation de la methode rubidium-strontium pour la datation d'une schistosite de sediments peu metamorphises: application au Precambrien II de la boutonniere de Bou Azzer-El Graara (Anti-Atlas, Maroc). Earth Plan. Sci. Letters, v.22, p.404-412. https://doi.org/10.1016/0012-821X(74)90151-4
  11. Dolansky, L.M. (2007) Controls on the genesis of hydrothermal cobalt mineralization: insights from the mineralogy and geochemistry of the Bou Azzer deposits, Morocco. Unpublished Ph.D. Thesis, McGill University, Montreal, 192p.
  12. En-Naciri, A. (1995) Contribution a l'etude du district a Co, As, (Ni, Au, Ag) de Bou Azzer, Anti Atlas (Maroc), donnees mineralogiques et geochimiques; etude des inclusions fluides. Unpublished P.h.D thesis, Universite Orleans, France, 238p.
  13. Ennaciri, A., Barbanson, L. and Touray, J.C. (1995b) Mineralized hydrothermal solution cavities in the Co-As Ait Ahmane mine (Bou Azzer, Morocco). Mineralium Deposita, v.30, p.75-77. https://doi.org/10.1007/BF00208879
  14. En-Naciri, A., Barbanson, L. and Touray, J.C. (1997) Brine inclusions from the Co-As (Au) Bou Azzer district, Anti-Atlas Mountains, Morocco. Economic Geology, v.92, p.360-367. https://doi.org/10.2113/gsecongeo.92.3.360
  15. Essarraj, S., Boiron, M.C., Cathelineau, M., Banks, D.A. and Benharref, M. (2005) Penetration of surface-evaporated brines into the Proterozoic basement and deposition of Co and Ag at Bou Azzer (Morocco): Evidence from fluid inclusions. Journal of African Earth Sciences, v.41, p.25-39. https://doi.org/10.1016/j.jafrearsci.2005.03.001
  16. Gervilla, F., Fanlo, I., Colas, V. and Subias, I. (2012) Mineral compositions and phase relations of Ni-Co-Fe arsenide ores from the Aghbar mine, Bou Azzer, Morocco. The Canadian Mineralogist, v.50, p.447-470. https://doi.org/10.3749/canmin.50.2.447
  17. Hassenforder, B. (1987) La Tectonique Panafricaine et Varisque de l'Anti-Atlas dans le Massif du Kerdous (Maroc). These de doctorat Es-Sciences. Universite de Strasbourg, 220p.
  18. Ikenne, M., Soderlund, U., Ernst, R.E., Pin, C., Youbi, N., El Aouli, E.H. and Hafid, A. (2017) A c. 1710 Ma mafic sill emplaced into a quartzite and calcareous series from Ighrem, Anti-Atlas - Morocco: Evidence that the Taghdout passive margin sedimentary group is nearly 1 Ga older than previously thought. Journal of African Earth Sciences, v.127, p.62-76. https://doi.org/10.1016/j.jafrearsci.2016.08.020
  19. Kaiser, H.F. (1958) The varimax criteria for analytical rotation in factor analysis, Psychometrica, v.23, p.141-51. https://doi.org/10.1007/BF02289233
  20. Leblanc, M. (1975) Ophiolites precambriennes et gites arsenies de cobalt: Bou Azzer (Maroc). Unpublished Ph.D. thesis, Universite de Paris VI, Paris, France, p.367.
  21. Leblanc, M. (1981) The late Proterozoic ophiolites of Bou Azzer (Morocco): evidence for Pan-African plate tectonics. Developments in Precambrian Geology, v.4, p.435-451. https://doi.org/10.1016/S0166-2635(08)70022-7
  22. Leblanc, M. and Billaud, P. (1982) Cobalt arsenide ore bodies related to an upper Proterozoic ophiolite; Bou Azzer (Morocco). Economic Geology, v.77, p.162-175. https://doi.org/10.2113/gsecongeo.77.1.162
  23. Leblanc, M. and Lbouabi, M. (1988) Native silver mineralisation along a rodingite tectonic contact between serpentinite and quartz-diorite (Bou Azzer, Morocco). Economic Geology, v.83, p.1379-1391. https://doi.org/10.2113/gsecongeo.83.7.1379
  24. Maacha, L. (2013) Etudes Metallogeniques Et Geophysiques des Mineralisations Cobaltiferes et Cupriferes de Bou-Azzer El Graara Anti-Atlas Maroc: Les Mineralisations de Cobalt, Arsenic, Nickel et Or associees a la serie ophiolitique. Unpublished Ph.D. Thesis, Universite Cadi Ayyad, Marrakech, 748p.
  25. Soulaimani, A., Razin, P., Youbi, N., Barbanson, L., Admou, H., Blein, O., Gasquet, D., Bouabdelli, M. and Anzar, C. (2013) Notice explicative de la Carte geologique du Maroc (1:50,000), feuille Al Gloa. Notes et Memoires du service Geologique du Maroc, n.532bis.
  26. Souiri, M., Aissa, M., Ahmed, H.A., El Azmi., Mezougane, H., Moussaid, A. and El Basbas, A. (2020) Hydrothermal alterations of the Bou Azzer-East Co-Ni-As-Au deposits (Central Anti-Atlas, Morocco). Geosciences Journal (In review)
  27. Souiri, M., Aissa, M., Ouguir, H., El Azmi, M., El Basbas, A., Mezougane, H., Moussaid, A. and Zouhair, M. (2019) Metaux precieux (Au-Ag) dans le gisement a Co-Ni-Fe-As de Bou Azzer Est (Anti Atlas central, Maroc). Magmatisme, Metamorphisme et Mineralisations Associees (3MA-11) (Abstract), El Jadida Avril 23-24, p.52-53.
  28. Thomas, R.J., Chevallier, L.P., Gresse, P.G., Harmer, R.E., Eglington, B.M., Armstrong, R.A., de Beer, C.H., Martini, J.E.J., de Kock, G.S., Macey, P.H. and Ingram, B.A. (2002) Precambrian evolution of the Sirwa window, Anti-Atlas orogen, Morocco. Precambrian Research, v.118, p.1-57. https://doi.org/10.1016/S0301-9268(02)00075-X
  29. Webographie Johnston, K., Hoef, JMV., Krivoruchko, K. and Lucas, N. (2001). ArcGIS$^{(R)}$ 9: using ArcGIS$^{(R)}$.