Petrology, mineral chemistry and geochemistry of chloritite associated with Neoproterozoic ophiolitic ultramafics in the Eastern Desert of Egypt, Arabian-Nubian Shield

• Autorzy: Abuamarah Bassam A. , Seddiki Amany M.A , Azer Mokhles K. , Bartoli Omar , Darwish Mahmoud H.

Identyfikatory

DOI

10.24425/agp.2024.151755

• Języki publikacji: EN

Abstrakty

EN

This study presents for the first time, the field observations, petrography, mineral chemistry and geochemistry of chloritite hosted in the Al-Barramiya Neoproterozoic ophiolite of the Eastern Desert of Egypt, Arabian-Nubian Shield (ANS). The Al-Barramiya ophiolite is one of the most important ophiolitic sequences exposed in the ANS. It is affected by different types of alterations including carbonatization, listvenitization, chloritization and rodingitization. The Al-Barramiya chloritite occurs as thin layers associated with highly serpentinized peridotite. It is a fine-grained rock entirely composed of chlorite (85–95 vol.%) with minor talc and accessory minerals (epidote, rutile, titanite, corundum and opaque minerals). The chlorite minerals in the chloritite are represented mainly by diabantite, while those in the serpentinites include ripidolite. Depending on the chemical composition of the chlorites, the chlorite in chloritite formed at temperatures ranging between 200 and 250°C, which are lower than those of the disseminated chlorite in the serpentinite (310–345 o C), indicating their formation in different hydrothermal stages. The chloritite samples are rich in total REE contents (17.9–27.3 ppm) compared with the associated serpentinites (0.69–0.87 ppm). They are characterized by slightly depleted LREE relative to HREE [(La/Lu)n = 0.8–0.9], with a moderately negative Eu-anomaly [(Eu/Eu*)n = 0.4–0.5]. The negative Eu-anomalies are derived from chloritization fluids or reflect the presence of talc in the chloritite. Based on field work, petrography, mineralogical and geochemical data, the studied chloritite has been interpreted as being derived from the associated serpentinized ultramafics by hydrothermal alterations. This is supported by an enrichment of chloritite in compatible trace elements (Cr = 2031–2534 ppm, Ni = 1264–1988 ppm, Co = 76–101 ppm) similar to that which is observed in the associate serpentinite.

Słowa kluczowe

EN

Arabian-Nubian Shield; Al-Barramiya ophiolite; Chloritite; Chloritization; Fore-arcsetting

PL

tarcza arabsko-nubijska; ofiolit Al-Barramiya; chlorytyt; chlorytyzacja; przedpole łuku

• Wydawca: Faculty of Geology of the University of Warsaw ; Komitet Nauk Geologicznych PAN
• Czasopismo: Acta Geologica Polonica
• Rocznik: 2025
• Tom: Vol. 75, no. 1
• Strony: art. no. e33
• Opis fizyczny: Bibliogr. 68 poz., rys., tab., wykr.

Twórcy

autor

Abuamarah Bassam A.

• Department of Geology and Geophysics, King Saud University, Saudi Arabia

autor

Seddiki Amany M.A

• Geology Department, Faculty of Science, New Valley University, El-Kharga, Egypt

autor

Azer Mokhles K.

• Geological Sciences Department, National Research Centre, Cairo, Egypt

autor

Bartoli Omar

• Geoscience Department, University of Padova, Padova, Italy

autor

Darwish Mahmoud H.

• Geology Department, Faculty of Science, New Valley University, El-Kharga, Egypt

Bibliografia

• 1. Abd El-Rahman, Y., Polat, A., Dilek, Y., Fryer, B.J., El-Sharkawy, M. and Sakran, S. 2009. Geochemistry and tectonic evolution of the Neoproterozoic incipient arc-fore-arc crust in the Fawakhir area, Central Eastern Desert of Egypt. Precambrian Research, 175, 116–134.
• 2. Abdel Kader, Z. 1974. Mineralogical and geochemical studies on some Egyptian Mg-rich layer silicates (chloritites, serpentinites and talcs), 270 pp. PhD thesis, Cairo University.
• 3. Abdel-Karim, A.M. 2000. Chlorite schists and rodingites in the mafic-ultramafic rocks from the central Eastern Desert of Egypt: Petrogenesis and metamorphic history. Earth Science Series, 14, 150–170.
• 4. Abuamarah, B.A. 2020. Geochemistry and fore-arc evolution of upper mantle peridotites in the Cryogenian Bir Umqophiolite, Arabian Shield, Saudi Arabia. International Geology Review, 62, 630–648.
• 5. Abuamarah, B.A., Alshehri, F., Azer, M.K. and Asimow, P.D. 2023. Geological and tectonic significance of rodingite in the Ess ophiolite, Arabian Shield, Saudi Arabia. Lithos, 448, p.107168.
• 6. Abuamarah, B.A., Asimow, P.D., Azer, M.K. and Ghrefat, H. 2020. Suprasubduction-zone origin of the podiform chromitites of the Bir Tuluhah ophiolite, Saudi Arabia, during Neoproterozoic assembly of the Arabian Shield. Lithos, 360–361, 105439.
• 7. Ahmed, A.H., Arai, S. and Attia, A.K. 2001. Petrological characteristics of podiform chromitites and associated peridotites of the Pan African ophiolite complexes of Egypt. Mineralium Deposita, 36, 72–84.
• 8. Akaad, M.K. and Noweir, M.A. 1980. Geology and lithostratigraphy of the Arabian Desert orogenic belt of Egypt between latitudes 25° 35′ and 26° 30′ N. Bulletin of Institute of Applied Geology, King Abdul Aziz University Jeddah, 4, 127−134.
• 9. Ali, R.A.M., Pitcairn, I.K., Maurice, A.E., Azer, M.K., Bakhit, B.R. and Shahien, M.G. 2020. Petrology and geochemistry of ophiolitic ultramafic rocks and chromitites across the Eastern Desert of Egypt: Insights into the composition and nature of a Neoproterozoic mantle and implication for the evolution of SSZ system. Precambrian Research, 337, 105565.
• 10. Ali, S., Azer, M. and Abdel-Karim, A.A. 2023. Origin and evolution of Neoproterozoic metaophiolitic mantle rocks from the eastern Desert of Egypt: Implications for tectonic and metamorphic events in the Arabian-Nubian Shield. Geologica Acta, 21 (6), 1–21, I–VII.
• 11. Arai, S. 1992. Chemistry of chromian spinel in volcanic rocks as a potential guide to magma chemistry. Mineralogical magazine, 56, 173–184.
• 12. Arif, M., Jan, M.Q. 2006. Petrotectonic significance of the chemistry of chromite in the ultramafic-mafic complexes of Pakistan. Journal of Asian Earth Sciences, 27, 628–646.
• 13. Armbruster, T., Bonazzi, P., Akasaka, M., Bermanec, V., Chopin, C., Gieré, R., Heuss-Assbichler, S., Liebscher, A., Men chetti, S., Pan, Y. and Pasero, M. 2006. Recommended nomenclature of epidote-group minerals. European Journal of Mineralogy, 18 (5), 551–567.
• 14. Azer, M.K. 2014. Petrological studies of Neoproterozoic serpentinized ultramafics of the Nubian Shield: Spinel compositions as evidence of the tectonic evolution of the Egyptian ophiolites .Acta Geologica Polonica, 64, 113–127.
• 15. Azer, M.K., Gahlan, H.A., Asimow, P.D., Mubarak, H.S. and Al-Kahtany, K.M. 2019. Multiple stages of carbonation and element redistribution during formation of ultramafic-hosted magnesite in Neoproterozoic ophiolites of the Arabian-Nubian Shield, Egypt. Journal of Geology, 127 (1), 81–107.
• 16. Azer, M.K. and Khalil, A.E.S. 2005. Petrological and mineralogical studies of Pan-African serpentinites at Bir Al-Edeid area. Central Eastern Desert, Egypt. Journal of African Earth Sciences, 43, 525–536.
• 17. Azer, M.K., Samuel, M.D., Ali, K.A., Gahlan, H.A., Stern, R.J., Ren, M. and Moussa, H.E. 2013. Neoproterozoic ophiolitic peridotites along the Allaqi-Heiani Suture, South Eastern Desert, Egypt. Mineralogy and Petrology, 107, 829–848.
• 18. Azer, M.K. and Stern, R.J. 2007. Neoproterozoic (835–720 Ma) serpentinites in the Eastern Desert, Egypt: Fragments of fore-arc mantle. The Journal of Geology, 115, 457–472.
• 19. Barnes, I. and O’Neil, J.R. 1969. The relationship between fluids in some fresh alpine-type ultramafics and possible modern serpentinization, western United States. Geological Society of America Bulletin, 80, 1947–1960.
• 20. Barnes, S.J. and Roeder, P.L. 2001. The Range of Spinel Compositions in Terrestrial Mafic and Ultramafic Rocks. Journal of Petrology, 42, 2279–2302.
• 21. Basta, E.Z. and Kader, Z.A. 1969. The mineralogy of Egyptian serpentinites and talcearbonates. Mineralogical Magazine, 37, 394–408.
• 22. Bloomer, S.H., Taylor, B., MacLeod, C.J., Stern, R.J., Fryer, P., Hawkins, J.W. and Johnson, L. 1995. Early arc volcanism and ophiolite problem: A perspective from drilling in the Western Pacific. In: Taylor, B. and Natland, J. (Eds), Active Margins and Marginal Basins of the Western Pacific, Geophysical Monograph, Vol. 88, 1–30. American Geophysical Union; Washington, DC.
• 23. Bonatti, E. and Michael, P.J. 1989. Mantle peridotites from continental rifts to oceanic basins to subduction zones. Earth and Planetary Science Letters, 91, 297–311.
• 24. Bourdelle, F. and Cathelineau, M. 2015. Low-temperature chlorite geothermometry: a graphical representation based on a T–R 2+–Si diagram. European Journal of Mineralogy, 27, 617–626.
• 25. Cárdenas-Párraga, J., García-Casco, A., Proenza, J., Harlow, G., Blanco-Quintero, I., Lázaro, C., Villanova-de-Benavent, C. and Núñez Cambra, K. 2017. Trace-element geochemistry of transform-fault serpentinite in high-pressure subduction mélanges (eastern Cuba): Implications for subduction initiation. International Geology Review, 59, 2041–2064.
• 26. Cathelineau, M. and Nieva, D. 1985. A chlorite solid solution geothermometer. The Los Azufrez (Mexico) geothermal system. Contributions to Mineralogy and Petrology, 91, 235–244.
• 27. Compagnoni, R., Cossio, R. and Regis, D. 2021. Corundum-bearing veins in chloritite from the Etirol-Levaz Austroalpine continental Slice (Val Tournenche, Aosta, Italy). Ofio liti, 46 (2), 119–129.
• 28. David, H., Tegyey, M., Le Metour, J. and Wyns, R. 1990. Chloritite vessels from the sultanate of Oman: a petrographical study applied to archeology, 951–958. Academy of Sciences; Paris.
• 29. Deer, W.A., Howie, R.A. and Zussman, J. 1992. An introduction to the rock-forming minerals, 698 pp. Longman Group Ltd; New York.
• 30. Deschamps, F., Godard, M., Guillot, S. and Hattori, K. 2013. Geochemistry of subduction zone serpentinites: A review. Lithos, 178, 96–127.
• 31. Dick, H.J.B. and Bullen, T. 1984. Chromian spinel as a petrogenetic indicator in abyssal and Alpine-type peridotites and spatially associated lavas. Contribution to Mineralogy and Petrology, 86, 54–76.
• 32. El Sayed, M.M., Furnes, H. and Mohamed, F.H. 1999. Geochemical constraints on the tectonomagmatic evolution of the late Precambrian Fawakhir ophiolite, Central eastern Desert, Egypt. Journal of African Earth Sciences, 29, 515–533.
• 33. El-Ramly, M.F. and Akaad, M.K. 1960. The basement complex in the Central Eastern Desert of Egypt between lat. 24o 30 and 25 o40 N. Geological Survey of Egypt, Paper, 35 (8), 1–32.
• 34. Farahat, E.S., El Mahalawi, M.M. and Hoinkes, G. 2004. Continental back-arc basin origin of some ophiolites from the Eastern Desert of Egypt. Mineralogy and Petrology, 82, 81–104.
• 35. Franz, G. and Liebscher, A. 2004. Physical and chemical properties of the epidote minerals – an introduction. Reviews in Mineralogy and Geochemistry, 56 (1), 1–81.
• 36. Gahlan H., Arai S. and Almadani, S.2015. Petrogenesis of carbonated meta-ultramafic lenses from the Neoproterozoic Heiani ophiolite, South Eastern Desert, Egypt: A natural analogue to CO2 sequestration. Journal of African Earth Sciences, 102, 102–115.
• 37. Gahlan, H.A., Azer, M.K. and Al-Kahtany, K.M. 2021. Petrogenesis and geodynamic setting of high-Cr chromitites in fore-arc peridotites: A case study from the Halaban ophiolite, Eastern Arabian Shield, Saudi Arabia. Lithos, 396, 106243.
• 38. Gahlan, H.A., Azer, M.K. and Asimow, P.D. 2018. On the relative timing of listvenite formation and chromian spinel equilibration in serpentinites. American Mineralogist, 103 (7), 1087–1102.
• 39. Gahlan, H.A., Azer, M.K., Asimow, P.D., Mubarak, H.S. and Al-Kahtany, K.M. 2020. Petrological characteristics of the Neoproterozoic Ess ophiolite mantle section, Arabian Shield, Saudi Arabia: a mineral chemistry perspective. International Journal of Earth Sciences, 109, 239–251.
• 40. Hey, M.H. 1954. A new review of the chlorites. Mineralogical Magazine, 30, 272–292.
• 41. Hillier, S. and Velde, B. 1991. Octahedral occupancy and the chemical composition of diagenetic (low-temperature) chlorites. Clay Minerals, 26, 149–168.
• 42. Ishii, T., Robinson, P.T., Maekawa, H. and Fiske, R. 1992. Petrological studies of peridotites from diapiric Serpentinite Seamounts in the Izu-Ogasawara-Mariana forearc, leg 125. In: Pearce, J., Stokking, L.B., et al. (Eds), Proceedings of the Ocean Drilling Project, Leg 125, 445–485. Scientific Results (College Station); Texas.
• 43. Jan, M.Q. and Windley, B.F. 1990. Chromian spinel-silicate chemistry in ultramafic rocks of the Jijal complex, northwest Pakistan. Journal of Petrology, 31, 667–715.
• 44. Khalil, A.E.S. and Azer, M.K. 2007. Supra-subduction affinity in the Neoproterozoic serpentinites in the Eastern Desert, Egypt: evidence from mineral composition. Journal of African Earth Sciences, 49, 136–152.
• 45. Khalil, A.E.S., Obeid, M.A. and Azer, M.K. 2014. Serpentinized Peridotites at the North Part of the Wadi Allaqi District (Egypt): Implications for the Tectono-Magmatic Evolution of Fore-arc Crust. Acta Geologica Sinica-English Edition, 88 (5), 1421–1436.
• 46. Kotschoubey, B., Villas, R.N. and Aires, B. 2016. Chloritites of the Tocantins Group, Araguaia fold belt, central-northern Brazil: Vestiges of basaltic magmatism and metallogenetic implications. Journal of South American Earth Sciences, 69, 171–193.
• 47. Kranidiotis, P. and MacLean, W.H. 1987. The systematics of chlorite alteration at the Phelps Dodge massive sulfide deposit, Matagami, Quebec. Economic Geology, 82, 1898–1911.
• 48. McDonough, W.F. and Sun, S.S. 1995. Composition of the Earth. Chemical Geology, 120, 223–253.
• 49. Moussa, H.E., Azer, M.K., Abou El Maaty, M.A., Maurice, A.E., Yanni, N.N., Akarish, A.I., Elnazer, A.A. and Elsagheer, M.A. 2021. Carbonation of Neoproterozoic mantle section and formation of gold-bearing listvenite in the Northern Nubian Shield. Lithos, 406–407, 106525.
• 50. Moussa, H.E., Mubarak, H.S., Azer, M.K., Surour, A.A., Asimow, P.D. and Kabesh, M.M. 2022. Multistage petrogenetic evolution of Neoproterozoic serpentinized ultramafic rocks and podiform chromitites at Hagar Dungash, Eastern Desert of Egypt. Precambrian Research, 369, 106507.
• 51. Mubarak, H.S., Azer, M.K., Surour, A.A., Moussa, H.E., Asimow, P.D. and Kabesh, M.M. 2020. Mineralogical and geochemical study of rodingites and associated serpentinized peridotite, Eastern Desert of Egypt, Arabian-Nubian Shield. Lithos, 374, 105720.
• 52. Obeid, M.A., Khalil, A.E.S. and Azer, M.K. 2016. Mineralogy, geochemistry and geotectonic significance of the Neoproterozoic ophiolite of Wadi Arais area, south Eastern Desert, Egypt. Internal Geological Review, 58, 687–702.
• 53. Ohara, Y., Stern, R.J., Ishii, T., Yurimoto, H. and Yamazaki, T. 2002. Peridotites from the Mariana Trough: first look at the mantle beneath an active back-arc basin. Contribution to Mineralogy and Petrology, 143, 1–18.
• 54. Paulick, H., Bach, W., Godard, M., Hoog, C.J., Suhr, G. and Harvey, J. 2006. Geochemistry of abyssal peridotites (Mid-Atlantic Ridge, 15 20′N, ODP Leg 209): implications for fluid/rock interaction in slow spreading environments. Chemical Geology, 234, 179–210.
• 55. Ramos, R.C., Koester, E., Vieira, D.T., Porcher, C.C., Gezatt, J.N., Fontes, T.P. and Silveira, R.L. 2018. A hybrid origin for the chloritite of the Arroio Grande Ophiolite (Southernmost Brazil) from U-Pb shrimp ages. In: Proceedings of the 49. Brazilian Congress of Geology; 7. Symposium on volcanism and associated environments; 9. Symposium of cretaceous from Brazil, 1–5, Federal University of Rio Grande do Sul, Brasil.
• 56. Salters, V.J.M. and Stracke, A. 2004 Composition of the depleted mantle. Geochemistry, Geophysics, Geosystems, 5 (5), Q05B07.
• 57. Shackleton, R.M. 1994. Review of late Proterozoic sutures, ophiolitic mélanges and tectonics of eastern Egypt and north Sudan. Geological Rundschau, 83, 537–546.
• 58. Sobolev, N.V. and Logvinova, A.M. 2005. Significance of accessory chrome spinels in identifying serpentinite paragenesis. International Geological Review, 47, 58–64.
• 59. Stern, R.J. 1994. Arc assembly and continental collision in the Neoproterozoic East African Orogen: implications for the consolidation of Gondwanaland. Annual Reviews of Earth and Planetary Science, 22, 319–351.
• 60. Stern, R.J., Johnson, P.R., Kröner, A. and Yibas, B. 2004. Neoproterozoic ophiolites of the Arabian-Nubian Shield. In: Kusky, T.M. (Ed.), Precambrian ophiolites and related rocks. Developments in Precambrian Geology, 13, 95–128.
• 61. Stormer, J.C. 1983. The effects of recalculation on estimates of temperature and oxygen fugacity from analyses of multicomponent iron-titanium oxides. American Mineralogist, 68 (5–6), 586–594.
• 62. Takla, M.A., Basta, F.F. and Surour, A.A. 1991. Chloritites at the contacts of some ophiolitic ultramafics, Eastern Desert, Egypt. Egyptian Mineralogist, 3, 151–165.
• 63. Takla, M.A., Basta, F.F. and Surour, A.A. 1992. Petrology and Mineral Chemistry of Rodingites associating the Pan-African Ultramafics of Sikait-Abu Rusheid area, South Eastern Desert, Egypt. Geology of the Arab World, 1, 491–507.
• 64. Takla, M.A. and Noweir, M.A. 1980. Mineralogy and mineral chemistry of the ultramafic mass of El-Rubshi Eastern Desert, Egypt. Neues Jahrbuch für Mineralogie-Abhandlungen, 140, 17–28.
• 65. Takla, M.A., Trommsdorff, V., Basta, F.F. and Surour, A.A. 2003. Margarite in ultramafic alteration zones (Blackwall) A new occurrence in Barramiya Area, Egypt. European Journal of Mineralogy, 15 (6), 991–999.
• 66. Uysal, I., Ersoy, E.Y., Karslı, O., Dilek, Y., Sadıklar, M.B., Ottley, C.J., Tiepolo, M. and Meisel, T. 2012. Coexistence of abyssal and ultra-depleted SSZ type mantle peridotites in a Neo-Tethyan Ophiolite in SW Turkey: Constraints from mineral composition, whole-rock geochemistry (major-trace-REE-PGE), and Re Os isotope systematic. Lithos, 132–133, 50–69.
• 67. Yavuz, F., Kumral, M., Karakaya, N., Karakaya, M. C. and Yildirim, D. K. 2015. A Windows program for chlorite calculation and classification. Computers and Geosciences, 81, 101–113.
• 68. Zimmer, M., Kröner, A., Jochum, K.P., Reischmann, T. and Todt, W. 1995. The Gabal Gerf complex: a Precambrian N-MORB ophiolite in the Nubian Shield, NE Africa. Chemical Geology, 123, 29–51.

Uwagi

Opracowanie rekordu ze środków MNiSW, umowa nr POPUL/SP/0154/2024/02 w ramach programu "Społeczna odpowiedzialność nauki II" - moduł: Popularyzacja nauki (2026).