Hafnium isotope variations in oceanic basalts
Hafnium isotope ratios generated by the beta(-) decay of Lu-176 are investigated in volcanic rocks derived from the suboceanic mantle. Hf-176/Hf-177 and Lu/Hf ratios were determined to precisions of 0.01-0.04% and 0.5%, respectively, by routine, low-blank chemistry. The Hf-176/Hf-177 ratio is found...
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1980
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ftnasantrs:oai:casi.ntrs.nasa.gov:19810033029 2023-05-15T16:49:50+02:00 Hafnium isotope variations in oceanic basalts Patchett, P. J. Tatsumoto, M. Unclassified, Unlimited, Publicly available Dec 1, 1980 http://ntrs.nasa.gov/search.jsp?R=19810033029 unknown http://ntrs.nasa.gov/search.jsp?R=19810033029 Accession ID: 81A17433 Copyright Other Sources 46 Geophysical Research Letters; 7; Dec. 198 1980 ftnasantrs 2012-02-15T14:36:58Z Hafnium isotope ratios generated by the beta(-) decay of Lu-176 are investigated in volcanic rocks derived from the suboceanic mantle. Hf-176/Hf-177 and Lu/Hf ratios were determined to precisions of 0.01-0.04% and 0.5%, respectively, by routine, low-blank chemistry. The Hf-176/Hf-177 ratio is found to be positively correlated with the Nd-143/Nd-144 ratio and negatively correlated with the Sr-87/Sr-86 and Pb-206/Pb-204 ratios, and to increase southwards along the Iceland-Reykjanes ridge traverse. An approximate bulk earth Hf-176/Hf-177 ratio of 0.28295 is inferred from the bulk earth Nd-143/Nd-144 ratio, which requires a bulk earth Lu/Hf ratio of 0.25, similar to the Juvinas eucrite. Midocean ridge basalts are shown to account for 60% of the range of Hf isotope ratios, and it is suggested that Lu-Hf fractionation is decoupled from Sm-Nd and Rb-Sr fractionation in very trace-element-depleted source regions as a result of partial melting. Other/Unknown Material Iceland NASA Technical Reports Server (NTRS) Reykjanes ENVELOPE(-22.250,-22.250,65.467,65.467) |
institution |
Open Polar |
collection |
NASA Technical Reports Server (NTRS) |
op_collection_id |
ftnasantrs |
language |
unknown |
topic |
46 |
spellingShingle |
46 Patchett, P. J. Tatsumoto, M. Hafnium isotope variations in oceanic basalts |
topic_facet |
46 |
description |
Hafnium isotope ratios generated by the beta(-) decay of Lu-176 are investigated in volcanic rocks derived from the suboceanic mantle. Hf-176/Hf-177 and Lu/Hf ratios were determined to precisions of 0.01-0.04% and 0.5%, respectively, by routine, low-blank chemistry. The Hf-176/Hf-177 ratio is found to be positively correlated with the Nd-143/Nd-144 ratio and negatively correlated with the Sr-87/Sr-86 and Pb-206/Pb-204 ratios, and to increase southwards along the Iceland-Reykjanes ridge traverse. An approximate bulk earth Hf-176/Hf-177 ratio of 0.28295 is inferred from the bulk earth Nd-143/Nd-144 ratio, which requires a bulk earth Lu/Hf ratio of 0.25, similar to the Juvinas eucrite. Midocean ridge basalts are shown to account for 60% of the range of Hf isotope ratios, and it is suggested that Lu-Hf fractionation is decoupled from Sm-Nd and Rb-Sr fractionation in very trace-element-depleted source regions as a result of partial melting. |
format |
Other/Unknown Material |
author |
Patchett, P. J. Tatsumoto, M. |
author_facet |
Patchett, P. J. Tatsumoto, M. |
author_sort |
Patchett, P. J. |
title |
Hafnium isotope variations in oceanic basalts |
title_short |
Hafnium isotope variations in oceanic basalts |
title_full |
Hafnium isotope variations in oceanic basalts |
title_fullStr |
Hafnium isotope variations in oceanic basalts |
title_full_unstemmed |
Hafnium isotope variations in oceanic basalts |
title_sort |
hafnium isotope variations in oceanic basalts |
publishDate |
1980 |
url |
http://ntrs.nasa.gov/search.jsp?R=19810033029 |
op_coverage |
Unclassified, Unlimited, Publicly available |
long_lat |
ENVELOPE(-22.250,-22.250,65.467,65.467) |
geographic |
Reykjanes |
geographic_facet |
Reykjanes |
genre |
Iceland |
genre_facet |
Iceland |
op_source |
Other Sources |
op_relation |
http://ntrs.nasa.gov/search.jsp?R=19810033029 Accession ID: 81A17433 |
op_rights |
Copyright |
_version_ |
1766040015551332352 |