Back to article

Figures and tables

Plume-lithosphere interaction, and the formation of fibrous diamonds

M.W. Broadley1,2,

1Geochemical Research Center, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
2Centre de Recherches Pétrographiques et Géochimiques, 54501 Vandoeuvre-Lès-Nancy Cedex, France

H. Kagi1,

1Geochemical Research Center, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
2Centre de Recherches Pétrographiques et Géochimiques, 54501 Vandoeuvre-Lès-Nancy Cedex, France

R. Burgess3,

3School of Earth and Environmental Science, University of Manchester, Oxford Road, Manchester M13 9PL, UK

D. Zedgenizov4,5,

4Sobolev Institute of Geology and Mineralogy, SB RAS, Koptyuga ave. 3, Novosibirsk 630090, Russia
5Novosibirsk State University, Pirogova st. 1, Novosibirsk 630090, Russia

S. Mikhail6,

6The School of Earth and Environmental Sciences, The University of St. Andrews, St. Andrews, UK

M. Almayrac2,

2Centre de Recherches Pétrographiques et Géochimiques, 54501 Vandoeuvre-Lès-Nancy Cedex, France

A. Ragozin4,5,

4Sobolev Institute of Geology and Mineralogy, SB RAS, Koptyuga ave. 3, Novosibirsk 630090, Russia
5Novosibirsk State University, Pirogova st. 1, Novosibirsk 630090, Russia

B. Pomazansky7,

7NIGP (Geo-Scientific research Enterprise) ALROSA Co., Chernyshevskoe rd. 7, 678170, Mirny, Sakha Republic, Russia

H. Sumino8

7NIGP (Geo-Scientific research Enterprise) ALROSA Co., Chernyshevskoe rd. 7, 678170, Mirny, Sakha Republic, Russia

Affiliations  |  Corresponding Author  |  Cite as  |  Funding information

Japanese Society for the Promotion of Science

Geochemical Perspectives Letters v8  |  doi: 10.7185/geochemlet.1825
Received 5 May 2018  |  Accepted 14 September 2018  |  Published 1 October 2018
Copyright © The Authors

Published by the European Association of Geochemistry
under Creative Commons License CC BY-NC-ND 4.0




Figure 1 Log-log plot of I/Cl vs. Br/Cl (mol/mol) for the Nyurbinskaya diamonds. Seawater, average mantle, marine pore fluids, altered oceanic crust fluids (AOC) and Canadian diamonds are shown for reference (Johnson et al., 2000

Johnson, L.H., Burgess, R., Turner, G., Milledge, H.J., Harris, J.W. (2000) Noble gas and halogen geochemistry of mantle fluids: comparison of African and Canadian diamonds. Geochimica et Cosmochimica Acta 64, 717-732.

; Muramatsu et al., 2007

Muramatsu, Y., Doi, T., Tomaru, H., Fehn, U., Takeuchi, R., Matsumoto, R. (2007) Halogen concentrations in pore waters and sediments of the Nankai Trough, Japan: Implications for the origin of gas hydrates. Applied Geochemistry 22, 534-556.

and references therein; Kendrick et al., 2012

Kendrick, M.A., Kamenetsky, V.S., Phillips, D., Honda, M. (2012) Halogen systematics (Cl, Br, I) in mid-ocean ridge basalts: a Macquarie Island case study. Geochimica et Cosmochimica Acta 81, 82-93.

; Chavrit et al., 2016

Chavrit, D., Burgess, R., Sumino, H., Teagle, D.A., Droop, G., Shimizu, A., Ballentine, C.J. (2016) The contribution of hydrothermally altered ocean crust to the mantle halogen and noble gas cycles. Geochimica et Cosmochimica Acta 183, 106-124.

). Nyurbinskaya diamonds range from mantle values towards enriched Br/Cl, similar to AOC and Canadian diamonds suggesting there has been an input of Br-rich fluids to the Siberian lithosphere. Uncertainties are 1σ when shown and are often smaller than symbol size.
Back to article | Download in Powerpoint


Figure 2 3He/4He vs. 4He concentrations from crushing and laser heating (open symbols) of Nyurbinskaya diamonds. 3He/4He from the cubic diamonds are higher than the cloudy and coated diamonds and plot above MORB values suggesting the diamond-hosted inclusions contain a mixture of lithospheric and deep mantle volatiles. Uncertainties shown are 1σ and for 4He concentrations are smaller than symbol size.
Back to article | Download in Powerpoint


Figure 3 (a) Neon three-isotope plot for crushing of Nyurbinskaya diamonds. (b) Zoomed in section showing data from laser extraction (open symbols) plus the crushing data from the cubic diamonds. Diamonds show excess in 20Ne/22Ne and 21Ne/22Ne relative to air and plot intermediate between the MORB-Air mixing line and the Solar-Air mixing line. Dashed red line is a regression line fitted through all the Nyurbinskaya diamond data and forced through the atmospheric values. Dashed black line is the trend for Udachnaya olivine xenocrysts (Sumino et al., 2006

Sumino, H., Kaneoka, I., Matsufuji, K., Sobolev, A.V. (2006) Deep mantle origin of kimberlite magmas revealed by neon isotopes. Geophysical Research Letters 33, L16318, doi: 10.1029/2006GL027144.

). Uncertainties are 1σ.
Back to article | Download in Powerpoint


Figure 4 Total nitrogen concentrations vs. the percentage of nitrogen in the B aggregated state. Each point is from the analysis of a single diamond, full symbols are from the bulk measurement, whilst open symbols are from the fibrous coat or cloudy interior of the coated and cloudy diamonds respectively. Isotherms are calculated assuming a temperature range between 1200 °C (solid lines) and 1300 °C (dashed lines) as reported for Udachnaya xenolith (Boyd et al., 1997

Boyd, F.R., Pokhilenko, N.P., Pearson, D.G., Mertzman, S.A., Sobolev, N.V., Finger, L.W. (1997) Composition of the Siberian cratonic mantle: evidence from Udachnaya peridotite xenoliths. Contributions to Mineralogy and Petrology 128, 228-246.

) and assumed residence times between 1 Ma and 200 Ma. All diamonds indicate a residence time of less than 200 Ma at the temperature estimated for the Siberian SCLM at 360Ma (eruption age of Nyurbinskaya and Udachnaya kimberlites).
Back to article | Download in Powerpoint