Journal Articles (Earth and Atmospheric Sciences)

2023-01-01

Regier, Margo E., Smit, Karen V., Chalk, Thomas B., Stachel, Thomas, Stern, Richard A., Smith, Evan M., Foster, Gavin L., Bussweiler, Yannick, Debuhr, C., Burnham, Antony D., Harris, Jeff W., Pearson, D. Graham

Abstract Boron is a quintessential crustal element but its conspicuous presence in diamond – a mantle mineral – raises questions about potential subduction pathways for boron and other volatiles. It has been a long-standing goal to characterize the isotopic composition of boron in blue,...

2016-11-16

Hogberg, Katie, Stachel, Thomas, Stern, Richard A.

Using stable isotope data obtained on multiple aliquots of diamonds from worldwide sources, it has been argued that carbon and nitrogen in diamond are decoupled. Here we re-investigate the carbon–nitrogen relationship based on the most comprehensive microbeam data set to date of stable isotopes...

2022-01-01

Carvalho, Luísa D.V., Stachel, Thomas, Pearson, D. Graham, Fuck, Reinhardt A., Jalowitzki, Tiago, Timmerman, Suzette, Steele-Maclnnis, Matthew, Gonçalves, Guilherme O., Pereira, Rogério Silvestre, Scholz, Ricardo

Abstract The lithospheric mantle underpinning the Alto Paranaíba Igneous Province, southwestern São Francisco Craton, was investigated through a study of 82 diamonds and their mineral inclusions from the Coromandel (Douradinho River), Verde River (northern Coromandel), Abaeté, Frutal, and Romaria...

2022-01-01

Lai, Mei Yan, Stachel, Thomas, Stern, Richard A., Hardman, Matthew F., Pearson, D. Graham, Harris, Jeff W.

Abstract Inclusion-bearing diamonds from the Koidu kimberlite complex, Sierra Leone (West African Craton) were analyzed in situ for carbon and nitrogen isotope compositions, nitrogen concentrations and nitrogen aggregation states. In a suite of 105 diamonds, 78% contain eclogitic mineral...

2023-01-01

Lai, Mei Yan, Stachel, Thomas, Stern, Richard A., Li, Kan, Pearson, D. Graham, Harris, Jeff W.

Abstract Eclogitic diamond formation can be associated with interactions between subducted slabs and ambient mantle. To gain a better understanding of the extent of chemical exchange between slabs and ambient mantle and the mechanisms of coeval diamond formation, we examined 16 diamonds with...

2017-02-01

E. Jackson, Simon E., Bussweiler, Yannick, Hardman, Matthew, Stern, Richard A., Brey, Gerhard Peter, Kjarsgaard, B.A., Pearson, Graham, Stachel, Thomas

This study provides an experimental calibration of the empirical Al-in-olivine thermometer for mantle peridotites proposed by De Hoog et al. (2010). We report Al concentrations measured by secondary ion mass spectrometry (SIMS) in olivines produced in the original high-pressure, high-temperature,...

2016-07-01

Luth, R. W., Stone, Rebecca, Menzies, Andrew, Bussweiler, Yannick, Pearson, Graham, Stachel, Thomas, Kjarsgaard, B. A.

Megacrystic (>1 cm) clinopyroxene (Cr-diopside) and garnet (Cr-pyrope) xenocrysts within kimberlites from Lac de Gras (Northwest Territories, Canada) contain fully crystallized melt inclusions. These ‘polymineralic inclusions’ have previously been interpreted to form by necking down of melts at...