Abstract
The study develops a new approach utilizing parameters of trigonal etch pits on diamond crystals to infer the conditions of diamond residence in kimberlite magma. Diamond crystals from dissolution experiments conducted at 1 GPa and 1150–1350 °C in the presence of H2O-rich or CO2-rich fluid were studied with atomic force microscopy (AFM). The AFM data of resorbed diamond surfaces show that much deeper surface relief was produced in CO2 fluid. It also clearly distinguishes the profiles of the trigonal etch pits forming regular flat-bottomed trigons in H2O fluid, and round- or pointed-bottomed trigons in CO2 fluid. The relationship between the diameter and the depth of the trigonal pits is found to be another important indicator of the fluid composition. Dissolution in H2O fluid develops trigons with constant diameter and variable depth where the diameter increases with temperature. Trigons developed in CO2 fluid have a large range of diameters showing a strong positive correlation with the depth. The developed criteria applied to the natural diamond crystals from three Ekati Mine kimberlites indicate significant variation in CO2–H2O ratio and temperature of their magmatic fluid. This conclusion based on diamond resorption agrees with the mineralogy of microphenocrysts and groundmass of the studied kimberlites offering new method to study crystallization conditions of kimberlite magma.
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References
Angus JC, Dyble TJ (1975) Etching models for a 111 diamond surface: calculation of trigon slopes. Surf Sci 50:157–177
Arima M, Kozai Y (2008) Diamond dissolution rates in kimberlitic melts at 1300–1500 degrees C in the graphite stability field. Eur J Mineral 20(3):357–364
Armstrong JP, Wilson M, Barnett RL, Nowicki T, Kjarsgaard BA (2004) Mineralogy of primary carbonate-bearing hypabyssal kimberlite, Lac de Gras, Slave Province, Northwest Territories, Canada. Lithos 76:415–433
Crawford BB, Porritt L, Nowicki T, Carlson JA (2006) Key geological characteristics of the Koala Kimberlite, Ekati Diamond Mine, Canada. In: Kimberlite Emplacement Workshop, Saskatoon, Canada
Fedortchouk Y, Canil D (2004) Intensive variables in kimberlite magmas, Lac de Gras, Canada and implications for diamond survival. J Petrol 45(9):1725–1745
Fedortchouk Y, Canil D (2009) Diamond oxidation at atmospheric pressure: development of surface features and the effect of oxigen fugacity. Eur J Mineral 21:623–635
Fedortchouk Y, Zhang Z (2011) Diamond resorption: link to metasomatic events in the mantle or record of magmatic fluid in kimberlite magma? Can Mineral 49(3):707–719
Fedortchouk Y, Canil D, Carlson JA (2005) Dissolution forms in Lac de Gras diamonds and their relationship to the temperature and redox state of kimberlite magma. Contrib Mineral Petrol 150:54–69
Fedortchouk Y, Canil D, Semenets E (2007) Mechanisms of diamond oxidation and their bearing on the fluid composition in kimberlite magmas. Am Mineral 92:1200–1212
Fedortchouk Y, Matveev S, Carlson JA (2010) H2O and CO2 in kimberlitic fluid as recorded by diamonds and olivines in several Ekati Diamond Mine kimberlites, Northwest Territories, Canada. Earth Planet Sci Lett 289:549–559
Fedortchouk Y, Manghnani MH, Hushur A, Shiryaev A, Nestola F (2011) An atomic force microscopy study of diamond dissolution features: the effect of H2O and CO2 in the fluid on diamond morphology. Am Mineral 96:1768–1775
Griffin WL, Smith D, Boyd FR, Cousens DR, Ryan CG, Sie SH, Suter GF (1989) Trace-element zoning in garnets from sheared mantle xenoliths. Geochim Cosmochim Acta 53:561–567
Gurney JJ, Hildebrand PR, Carlson JA, Fedortchouk Y, Dyck DR (2004) The morphological characteristics of diamonds from the Ekati property, Northwest Territories, Canada. Lithos 77:21–38
Khokhryakov AF, Palyanov YN (2006) Revealing of dislocations in diamond crystals by the selective etching method. J Cryst Growth 293:469–474
Khokhryakov AF, Pal’yanov YN (2010) Influence of the fluid composition on diamond dissolution forms in carbonate melts. Am Mineral 95(10):1508–1514
Khokhryakov AF, Pal’yanov YN, Sobolev NV (2002) Crystal morphology as an indicator of redox conditions of natural diamond dissolution. Dokl Earth Sci 385(5):534–537
Klein-BenDavid O, Izraeli ES, Hauri E, Navon O (2007) Fluid inclusions in diamonds from the Diavik mine, Canada and the evolution of diamond-forming fluids. Geochim Cosmochim Acta 71:723–744
Kozai Y, Arima M (2005) Experimental study on diamond dissolution in kimberliteic and lamproitic melts at 1300–1420 °C and 1 GPa with controlled oxygen partial pressure. Am Mineral 90:1759–1766
Kressall R, Fedortchouk Y (2013) Major- and trace-element composition of Fe–Ti oxides from the Lac de Gras kimberlites. In: GAC-MAC meeting, Winnipeg, Canada
Mendelssohn MJ, Milledge HJ (1995) Morphological characteristics of diamond populations in relation to temperature-dependent growth and dissolution rates. Int Geol Rev 37:285–312
Mitchell RH (2013) Paragenesis and oxygen isotopic studies of Serpentine in Kimberlite. J Geol Soc India 1(Special Issue: Proceedings of 10 IKC):1–12
Nowicki T, Crawford B, Dyck D, Carlson J, McElroy R, Oshust P, Helmstaedtd H (2004) The geology of kimberlite pipes of the Ekati property, Northwest Territories, Canada. Lithos 76:1–27
Nowicki T, Porritt L, Crawford B, Kjarsgaard B (2008) Geochemical trends in kimberlites of the Ekati property, Northwest Territories, Canada: insights on volcanic and resedimentation processes. J Volcanol Geoth Res 174:117–127
Pasteris JD (1983) Spinel zonation in the De Beers kimberlite, South Africa: possible role of phlogopite. Can Mineral 21:41–58
Robinson DN (1979) Surface textures and other features of diamonds. PhD Thesis. University of Cape Town, South Africa
Rohrbach A, Schmidt MW (2011) Redox freezing and melting in the Earth’s deep mantle resulting from carbon–iron redox coupling. Nature 472:209–212
Skinner EMW, Marsh JS (2004) Distinct kimberlite pipe classes with contrasting eruption processes. Lithos 76(1–4):183–200
Stachel T, Aulbach S, Brey GP, Harris JW, Leost I, Tappert R, Viljoen KSF (2004) The trace element composition of silicate inclusions in diamonds: a review. Lithos 77:1–19
Stagno V, Ojwang DO, McCammon CA, Frost DJ (2013) The oxidation state of the mantle and the extraction of carbon from Earth’s interior. Nature 493:84–88
Stripp GR, Field M, Schumacher JC, Sparks RSJ, Cressey G (2006) Post-emplacement serpentinization and related hydrothermal metamorphism in a kimberlite from Venetia, South Africa. J Metamorph Geol 24:515–534
Zhang Z, Fedortchouk Y (2012) Records of mantle metasomatism in the morphology of diamonds from the Slave craton. Eur J Mineral 24:619–632
Zhang Z, Fedortchouk Y, Hanley J (2015) Evolution of diamond resorption in a silicic aqueous fluid at 1–3 GPa: application to kimberlite emplacement and mantle metasomatism. Lithos 227:179–193
Acknowledgments
The author thanks J. Carlson and BHPBilliton Diamonds Inc. for providing diamond parcels, A. Logvinova for providing diamond crystals for experiments, and T. Stachel for the help with FTIR work. Patricia Scallion is thanked for the help with SEM work and Institute for Research in Materials for the access to the FESEM funded by Canada Foundation for Innovation. The thorough reviews by G. Brey and an anonymous reviewer helped to significantly improve the manuscript. This research was supported by NSERC of Canada Discovery grant to YF.
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Communicated by Max W. Schmidt.
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Fedortchouk, Y. Diamond resorption features as a new method for examining conditions of kimberlite emplacement. Contrib Mineral Petrol 170, 36 (2015). https://doi.org/10.1007/s00410-015-1190-z
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DOI: https://doi.org/10.1007/s00410-015-1190-z