Mineralium Deposita

, Volume 38, Issue 6, pp 695–714 | Cite as

Age constraints on Tarkwaian palaeoplacer and lode-gold formation in the Tarkwa-Damang district, SW Ghana

  • Jon-Philippe Pigois
  • David I. Groves
  • Ian R. Fletcher
  • Neal J. McNaughton
  • Lawrence W. Snee
Article

Abstract

Two major epigenetic gold-forming events are recorded in the world-class gold province of southwest Ghana. A pre-Tarkwaian event was the source of the world-class Tarkwa palaeoplacers whereas post-Birimian and Tarkwaian deformation, which was related to the Eburnean orogeny, gave rise to the world-class (e.g. Prestea) to giant (e.g. Obuasi) orogenic gold deposits which have made the region famous for more than 2,500 years. A maximum age of 2133±4 Ma for Tarkwaian sedimentation is provided by 71 of 111 concordant SHRIMP II U–Pb dates from detrital zircons in Tarkwaian clastic rocks from Damang and Bippo Bin, northeast of Tarkwa. The overall data distribution broadly overlaps the relatively poorly constrained ages of Birimian volcanism and associated Dixcove-type granitoid emplacement, indicating syntectonic development of the Tarkwaian sedimentary basin. These zircon ages argue against derivation of the palaeoplacer gold from an orogenic gold source related to the compressional phase of an orogeny significantly older than the Eburnean orogeny. Instead, they suggest that the gold source was either orogenic gold lodes related to an earlier compressional phase of a diachronous Eburnean orogeny or ca. 2200–2100 Ma intrusion-related gold lode. The CO2-rich fluid inclusions in associated vein-quartz pebbles are permissive of either source. At the Damang deposit, an epigenetic, orogenic lode-gold system clearly overprinted, and sulphidised low-grade palaeoplacer hematite–magnetite gold occurrences in the Banket Series conglomerate within the Tarkwaian sedimentary sequence. Gold mineralisation is demonstrably post-peak metamorphism, as gold-related alteration assemblages overprint metamorphic assemblages in host rocks. In alteration zones surrounding the dominant, subhorizontal auriferous quartz veins, there are rare occurrences of hydrothermal xenotime which give a SHRIMP U–Pb age of 2063±9 Ma for gold mineralisation. The similar structural timing of epigenetic gold mineralisation in Tarkwaian host rocks at Damang to that in mainly Birimian host rocks elsewhere in southwest Ghana, particularly at Obuasi, suggests that 2063±9 Ma is the best available age estimate for widespread orogenic gold mineralisation in the region. Argon–argon ages of 2029±4 and 2034±4 Ma for hydrothermal biotite from auriferous quartz veins appear to represent uplift and cooling of the region below about 300 °C, as estimates of the temperature of gold mineralisation are higher, at around 400 °C. If peak metamorphism, with temperatures of about 550 °C, is assumed to have occurred at about 2100 Ma, the biotite ages, in combination with the xenotime age, suggest a broadly constant uplift rate for the region of about 1 km per 10 million years from about 2100 to 2025 Ma.

Keywords

Gold Geochronology Xenotime Damang Tarkwa Ashanti Ghana 

Notes

Acknowledgments

This study is part of a PhD study funded by a University Postgraduate Award and Ranger Minerals Ltd. Ghana Gold Fields Ltd. is thanked for permission to publish the information presented in this study. Special thanks are directed towards Andrew Tunks for his guidance in the field. Other Abosso Goldfields Ltd. geologists, Sam Annie, Gary Brabham, Felix Dong, Emmanuel Gladzah, Mike McKevitt, Gyedu Nkieta and Jamie Rogers, are also thanked for their support and advice during fieldwork. Paul Karpeta is thanked for useful suggestions. Sample preparation was at the UWA Mineral Separation Laboratory under the expert supervision of Marion Marshall. All SEM and WDS work was undertaken at the University of Western Australia in the Centre for Microscopy and Microanalysis directed by Brendan Griffin. Zircon and xenotime analyses were performed at the Western Australian SHRIMP facilities operated by a university-government consortium with ARC support. Biotite 40Ar/39Ar analyses were performed at the US Geological Survey in Denver. The paper has been greatly improved based on the critical reviews of Drs. Rich Goldfarb and Noreen Vielreicher.

Supplementary material

126_2003_360_MOESM1_ESM.pdf (109 kb)
Appendix (PDF 109 KB)

References

  1. Allibone AH, McCuaig TC, Harris D, Etheridge M, Munroe S, Byrne D, Amanor J, Gyapong W (2002a) Structural controls on gold mineralization at the Ashanti deposit, Obuasi, Ghana. In: Goldfarb RJ, Nielsen RL (eds) Integrated methods for discovery: global exploration in the twenty-first century. Soc Econ Geol Spec Publ 9:65–93Google Scholar
  2. Allibone AH, Teasdale J, Cameron G, Ethridge M, Uttley P, Soboh A, Appiah-Kubi J, Adanu A, Arthur R, Mamphey J, Odoom B, Zuta J, Tsikata A, Pataye F, Famiyeh S (2002b) Timing and structural controls on gold mineralization at the Bogoso gold mine, Ghana, West Africa. Econ Geol 97:949–969CrossRefGoogle Scholar
  3. Appiah H (1991) Geology and mine exploration trends of Prestea Goldfields, Ghana. J Afr Earth Sci 13:235–241CrossRefGoogle Scholar
  4. Blenkinsop T, Schmidt Mumm A, Kumi R, Sangmor S (1994) Structural geology of the Ashanti gold mine. In: Oberthür T (ed) Metallogenesis of selected gold deposits in Africa. Geol Jahrb D100:131–153Google Scholar
  5. Bonhomme M (1962) Contribution a l'étude géochronologique de la plate-forme de l'ouest africain. Unité d'Enseignement et de Recherche de Sciences Exactes et Naturelles, Clermont-FerrandGoogle Scholar
  6. Brabham G (1998) The regional geological setting and nature of the Damang stockwork gold deposit—a new type of deposit in Ghana. MSc Thesis, University of Western AustraliaGoogle Scholar
  7. Bucher K, Frey M (1994) Petrogenesis of metamorphic rocks. Springer, Berlin Heidelberg New YorkGoogle Scholar
  8. Compston W, Williams IS, Meyer CE (1984) U-Pb geochronology of zircons from lunar breccia 73217 using a sensitive high mass-resolution ion microprobe. In: Boynton WV, Schubert G (eds) Proc 14th Lunar and Planetary Science Conf, part 2. J Geophys Res B 89:525–534CrossRefGoogle Scholar
  9. Cozens B (1989) The geology and structure of the Konongo gold mine, Ghana, and its implications in exploration. In: Le Maitre RW (ed) Pathways in geology—essays in honour of Edwin Sherbon Hills. Blackwell, Melbourne, pp 463Google Scholar
  10. Davis DW, Hirdes W, Schaltegger U, Nunoo EA (1994) U-Pb age constraints on deposition and provenance of Birimian and gold-bearing Tarkwaian sediments in Ghana, West Africa. Precambrian Res 67:89–107CrossRefGoogle Scholar
  11. Eisenlohr BN (1989) The structural geology of Birimian and Tarkwaian rocks of southwest Ghana. Bundesanstalt Geowissen Rohstoffe, HannoverGoogle Scholar
  12. Eisenlohr BN (1992) Conflicting evidence on the timing of mesothermal and paleoplacer gold mineralization in early Proterozoic rocks from Southwest Ghana, West Africa. Miner Deposita 27:23–29CrossRefGoogle Scholar
  13. Eisenlohr BN, Hirdes W (1992) The structural development of the early Proterozoic and Birimian and Tarkwaian rocks of southwest Ghana, West Africa. J Afr Earth Sci 14:313–325CrossRefGoogle Scholar
  14. England GL, Rasmussen B, McNaughton NJ, Fletcher IR, Groves DI, Krapez B (2001) SHRIMP U-Pb ages of diagenetic and hydrothermal xenotime from the Archaean Witwatersrand Supergroup of South Africa. Terra Nova 13:360–367CrossRefGoogle Scholar
  15. Fletcher IR, Rasmussen B, McNaughton NJ (2000) SHRIMP U–Pb geochronology of authigenic xenotime and its potential for dating sedimentary basins. Aust J Earth Sci 47:845–859CrossRefGoogle Scholar
  16. Goldfarb RJ, Groves DI, Gardoll S (2001) Orogenic gold and geologic time: a global synthesis. Ore Geol Rev 18:1–75CrossRefGoogle Scholar
  17. Groves DI, Goldfarb RJ, Gebre-Mariam M, Hagemann SG, Robert F (1998) Orogenic gold deposits: a proposed classification in the context of their crustal distribution and relationship to other gold deposit types. Ore Geol Rev 13:7–27CrossRefGoogle Scholar
  18. Groves DI, Goldfarb RJ, Knox-Robinson CM, Ojala J, Gardoll S, Yun GY, Holyland P (2000) Late kinematic timing of orogenic gold deposits and significance for computer-based exploration techniques with emphasis on the Yilgarn Block, Western Australia. Ore Geol Rev 17:1–38CrossRefGoogle Scholar
  19. Harrison TM, Duncan I, McDougall I (1985) Diffusion of 40Ar in biotite; temperature, pressure and compositional effects. Geochim Cosmochim Acta 49:2461–2468CrossRefGoogle Scholar
  20. Hirdes W, Davis DW (1998) First U-Pb zircon age of extrusive volcanism in the Birimian Supergroup of Ghana/West Africa. J Afr Earth Sci 27:291–294CrossRefGoogle Scholar
  21. Hirdes W, Nunoo B (1994) The Proterozoic paleoplacers at Tarkwa Gold Mine, SW Ghana: sedimentology, mineralogy, and precise age dating of the Main Reef and West Reef, and bearing on the investigations on the source area aspects. In: Oberthür T (ed) Metallogenesis of selected gold deposits in Africa. Geol Jahrb D100:247–311Google Scholar
  22. Hirdes W, Saager R, Leube A (1988) New structural, radiometric and mineralogical aspects of the Au-bearing Tarkwaian Group of Ghana. Bicentennial Gold '88, Melbourne Abstr, pp 146–148Google Scholar
  23. Hirdes W, Davis DW, Eisenlohr BN (1992) Reassessment of Proterozoic granitoid ages in Ghana on the basis of U/Pb zircon and monazite dating. Precambrian Res 56:89–96CrossRefGoogle Scholar
  24. Hirdes W, Senger R, Adjei J, Efa E, Loh G, Tettey A (1993) Explanatory notes for the geological map of southwest Ghana 1:100,000 sheets Wiawso (0603C), Kukuom (0603B), Goaso (0603A), Sunyani (0703D), Berekum (0703C). Geol Jahrb B83Google Scholar
  25. Höhndorf A, Oberthür T, Gast L, Vetter U, Schmidt Mumm A (1994) Lead isotope systematics at the Ashanti mine, Obuasi, Ghana. In: Oberthür T (ed) Metallogenesis of selected gold deposits in Africa. Geol Jahrb D100:247–311Google Scholar
  26. John T, Klemd R, Hirdes W, Loh G (1999) The metamorphic evolution of the Paleoproterozoic (Birimian) volcanic Ashanti belt (Ghana, West Africa). Precambrian Res 98:11–30CrossRefGoogle Scholar
  27. Junner NR, Hirst T, Service H (1942) The Tarkwa Goldfield. Gold Coast Geological Survey, AccraGoogle Scholar
  28. Kesse GO (1985) The mineral and rock resources of Ghana. Balkema, RotterdamGoogle Scholar
  29. Klemd R, Hirdes W, Olesch M, Oberthür T (1993) Fluid inclusions in quartz-pebbles of the gold-bearing Tarkwaian conglomerates of Ghana as guides to their provenance area. Miner Deposita 28:334–343CrossRefGoogle Scholar
  30. Kouamelan AN, Delor C, Peaucat JJ (1997) Geochronological evidence for reworking of Archean terrains during the Early Proterozoic (2.1 Ga) in the western Côte d'Ivoire (Man Rise-West African Craton). Precambrian Res 86:177–199CrossRefGoogle Scholar
  31. Krapez B, Brown SJA, Hand J, Barley ME, Cas RAF (2000) Age constraints on recycled crustal and supracrustal sources of Archaean metasedimentary sequences, Eastern Goldfields Province, Western Australia; evidence from SHRIMP zircon dating. In: Sylvester PJ (ed) Continent formation, growth and recycling. Elsevier, Amsterdam, pp 89–133Google Scholar
  32. Lang JR, Baker T (2001) Intrusion-related gold systems: the present level of understanding. Miner Deposita 36:477–489CrossRefGoogle Scholar
  33. Lawrance LM, Griffin BJ (1994) Crystal features of supergene gold at Hannan South, Western Australia. Miner Deposita 29:391–398CrossRefGoogle Scholar
  34. Leube A, Hirdes W, Mauer R, Kesse GO (1990) The Early Proterozoic Birimian Supergroup of Ghana and some aspects of its associated gold mineralization. Precambrian Res 46:139–165CrossRefGoogle Scholar
  35. Lonrho Ltd (1974) Tarkwa and Abosso Mines, feasibility study. Ministry of Lands and Mineral Resources, AccraGoogle Scholar
  36. Manu J, Agyei EK (1993) Minimum Au mineralization age of the Birimian in Ghana. In: Proc 9th Int Geol Conf Regional Trends in African Geology, Accra, 1992, pp 234–239Google Scholar
  37. Marston RJ, Woolrich P, Kwesie J (1993) Closely associated stockwork and palaeoplacer gold mineralisation in the Early Proterozoic Tarkwaian System of Abosso, SW Ghana. In: Proc 9th Int Geol Conf Regional Trends in African Geology, Accra, 1992, pp 243–271Google Scholar
  38. McNaughton NJ, Rasmussen B, Fletcher IR (1999) SHRIMP uranium-lead dating of diagenetic xenotime in siliciclastic sedimentary rocks. Science 285:78–80CrossRefGoogle Scholar
  39. Milési JP, Feybesse JL, Ledru P, Dommanget A, Ouedraogo MF, Marcoux E, Prost A, Vinchon C, Sylvain JP, Johan V, Tegyey M, Calvez JY, Lagny P (1989) West African gold deposits in their Lower Proterozoic lithostructural setting. BRGM, OrléansGoogle Scholar
  40. Milési JP, Ledru P, Ankrah P, Johan V, Marcoux E, Vinchon C (1991) The metallogenic relationship between Birimian and Tarkwaian gold deposits in Ghana. Miner Deposita 26:228–238Google Scholar
  41. Milési JP, Ledru P, Feybesse JL, Dommanget A, Marcoux E (1992) Early Proterozoic ore deposits and tectonics of the Birimian orogenic belt, West Africa. Precambrian Res 58:305–344CrossRefGoogle Scholar
  42. Morrison GW, Rose WJ, Jaireth S (1991) Geological and geochemical controls on the silver content (fineness) of gold in gold-silver deposits. Ore Geol Rev 6:333–364CrossRefGoogle Scholar
  43. Mumin AH, Fleet ME, Chryssoulis SL (1994) Gold mineralization in As-rich mesothermal gold ores of the Bogosu-Prestea mining district of the Ashanti Gold Belt, Ghana: remobilization of "invisible" gold. Miner Deposita 29:445–460CrossRefGoogle Scholar
  44. Nelson DR (1997) Evolution of the Archaean granite-greenstone terranes of the Eastern Goldfields, Western Australia; SHRIMP U–Pb zircon constraints. In: Myers JS (ed) Archaean granite-greenstone geology of the Eastern Goldfields, Yilgarn Craton, Western Australia. Precambrian Res 83:57–81CrossRefGoogle Scholar
  45. Oberthür T, Vetter U, Schmidt Mumm A, Weiser T, Amanor JA, Gyapong WA, Kumi R, Blenkinsop TG (1994) The Ashanti gold mine at Obuasi, Ghana: mineralogical, geochemical, stable isotope and fluid inclusion studies on the metallogenesis of the deposit. In: Oberthür T (ed) Metallogenesis of selected gold deposits in Africa. Geol Jahrb D100:31–129Google Scholar
  46. Oberthür T, Schmidt Mumm A, Vetter U, Simon K, Amanor JA (1996) Gold mineralization in the Ashanti Belt of Ghana: Genetic constraints of the stable isotope geochemistry. Econ Geol 91:289–310CrossRefGoogle Scholar
  47. Oberthür T, Weiser T, Amanor JA, Chryssoulis SL (1997) Mineralogical siting and distribution of gold in quartz veins and sulfide ores of the Ashanti mine and other deposits in the Ashanti belt of Ghana: genetic implications. Miner Deposita 32:2–15CrossRefGoogle Scholar
  48. Oberthür T, Vetter U, Davis DW, Amanor JA (1998) Age constraints on gold mineralization and Paleoproterozoic crustal evolution in the Ashanti belt of southern Ghana. Precambrian Res 89:129–143CrossRefGoogle Scholar
  49. Ohmoto H, Beukes N, Gutzmer J, Nedachi M (1999) The formation of laterites approximately 2.3 billion years ago. Geol Soc Am Abstr Programs 31:225–226Google Scholar
  50. Petersson J, Whitehouse MJ, Eliasson T (2001) Ion microprobe U-Pb dating of hydrothermal xenotime from an episyenite; evidence for rift-related reactivation. Chem Geol 175:703–712CrossRefGoogle Scholar
  51. Phillips GN, Law JDM (2000) Witwatersrand gold fields; geology, genesis, and exploration. In: Hagemann SG, Brown PE (eds) Gold in 2000. Rev Econ Geol 13:439–500Google Scholar
  52. Pidgeon RT, Furfaro D, Clifford BA (1994) Investigation of the age and rate of deposition of part of the Gossan Hill Group, Golden Grove using conventional single grain zircon U-Pb geochronology. Geol Soc Aust Abstr Ser 37Google Scholar
  53. Rasmussen B (1996) Early-diagenetic REE-phosphate minerals (florencite, gorceixite, crandallite, and xenotime) in marine sandstones; a major sink for oceanic phosphorus. Am J Sci 296:601–632CrossRefGoogle Scholar
  54. Renne PR, Swisher CC, Deino AL, Owens T, Karner DB, DePaolo DJ (1997) Intercalibration of standards, absolute ages and uncertainties in Ar/Ar dating. Geol Soc Am Abstr Programs 29Google Scholar
  55. Samson SD, Alexander EC Jr (1987) Calibration of the interlaboratory 40Ar-39Ar dating standard, MMhb-1. In: Faure G (ed) New developments and applications in isotope geoscience. Chem Geol 66:27–34Google Scholar
  56. Santos JOS, Groves DI, Hartmann LA, Moura MA, McNaughton NJ (2001) Gold deposits of the Tapajos-Parima orogenic belt, Amazon Craton, Brazil. Miner Deposita 36:278–299CrossRefGoogle Scholar
  57. Sestini G (1973) Sedimentology of a paleoplacer: the gold-bearing Tarkwaian of Ghana. In: Amstutz GC, Bernard AJ (eds) Ores in sediments. Springer, Berlin Heidelberg New York, pp 275–305Google Scholar
  58. Sillitoe RH, Thompson JFH (1998) Intrusion-related vein gold deposits; types, tectono-magmatic settings and difficulties of distinction from orogenic gold deposits. Resources Geol 48:237–250CrossRefGoogle Scholar
  59. Smith JB, Barley ME, Groves DI, Krapez B, McNaughton NJ, Bickle MJ, Chapman HJ (1998) The Sholl shear zone, West Pilbara; evidence for a domain boundary structure from integrated tectonostratigraphic analyses, SHRIMP U–Pb dating and isotopic and geochemical data of granitoids. Precambrian Res 88:143–171CrossRefGoogle Scholar
  60. Snee LW (2002) Argon thermochronology of mineral deposits-a review of analytical methods, formulations, and selected applications. US Geol Surv Bull 2194Google Scholar
  61. Snee LW, Sutter JF, Kelly WC (1988) Thermochronology of economic mineral deposits; dating the stages of mineralization at Panasqueira, Portugal, by high-precision 40Ar/39Ar Ar age spectrum techniques on muscovite. Econ Geol 83:335–354CrossRefGoogle Scholar
  62. Strogen P (1988) The sedimentology, stratigraphy and structure of the Tarkwaian, Western Region, and its relevance to gold exploration and development. In: Proc Int Conf Geology of Ghana with Special Emphasis on Gold, Accra, 1988, pp R/1–R/39Google Scholar
  63. Suzuki K, Adachi M (1991) Precambrian provenance and Silurian metamorphism of the Tsubonosawa Paragenesis in the South Kitakami Terrane, Northeast Japan, revealed by the chemical Th-U-total Pb isochron ages of monazite, zircon and xenotime. Geochem J 25:357–376Google Scholar
  64. Sylvester PJ, Attoh K (1992) Lithostratigraphy and composition of 2.1 Ga greenstone belts of the West African craton and their bearing on crustal evolution and the Archean-Proterozoic boundary. J Geol 100:377–393CrossRefGoogle Scholar
  65. Taylor PN, Moorbath S, Leube A, Hirdes W (1992) Early Proterozoic crustal evolution in the Birimian of Ghana: constraints from geochronology and isotope geochemistry. Precambrian Res 56:97–111CrossRefGoogle Scholar
  66. Williams IS, Claesson S (1987) Isotopic evidence for the Precambrian provenance and Caledonian metamorphism of high grade paragenesis from the Seve Nappes, Scandinavian Caledonides. 2. Ion microprobe zircon U-Th-Pb. Contrib Mineral Petrol 97:205–217CrossRefGoogle Scholar
  67. Woodfield PD (1966) Geology of field sheet 91. Geological Survey of Ghana BullGoogle Scholar

Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  • Jon-Philippe Pigois
    • 1
  • David I. Groves
    • 1
  • Ian R. Fletcher
    • 1
  • Neal J. McNaughton
    • 1
  • Lawrence W. Snee
    • 2
  1. 1.Centre for Global Metallogeny, School of Earth and Geographical SciencesThe University of Western AustraliaCrawleyAustralia
  2. 2.US Geological SurveyDenver Federal CenterDenverUSA

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