CaltechAUTHORS
  A Caltech Library Service

Himalayan uplift and osmium isotopes in oceans and rivers

Sharma, M. and Wasserburg, G. J. and Hofmann, A. W. and Chakrapani, G. J. (1999) Himalayan uplift and osmium isotopes in oceans and rivers. Geochimica et Cosmochimica Acta, 63 (23-24). pp. 4005-4012. ISSN 0016-7037. https://resolver.caltech.edu/CaltechAUTHORS:20131119-140918131

Full text is not posted in this repository. Consult Related URLs below.

Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20131119-140918131

Abstract

Previous studies have shown that ^(187)Os/^(188)Os in seawater has become increasingly radiogenic over the last 40 Ma in a manner analogous to strontium. This rapid rise in the marine ^(187)Os/^(188)Os over the last 17 Ma has been attributed to an increase in the bulk silicate weathering rates resulting from the rise of the Himalayas and/or selective weathering and erosion of highly radiogenic organic rich ancient sediments. The key test of this hypothesis is the ^(187)Os/^(188)Os and the total osmium concentration of the Himalayan rivers. We report the concentration and isotopic composition of osmium in the Ganges, the Brahmaputra, and the Indus rivers. The ^(187)Os/^(188)Os of the Ganges close to its source (at Kaudiyal, 30°05′N, 78°50′E) is 2.65 and [Os] = 45 fM/kg. A second sample of the lower reaches of the Ganges at Patna (25°30′N, 85°10′E) gives ^(187)Os/^(188)Os =1.59 and [Os] = 171 fM/kg. The ^(187)Os/^(188)Os of the Brahmaputra at Guwahati (26°10′N, 91°58′E) is 1.07 and [Os] = 52 fM/kg. A sample of the Indus (Besham, 34°55′N, 72°51′E) has a ^(187)Os/^(188)Os of 1.2 and [Os] = 59 fM/kg. We infer that the Himalayas do not provide either a high flow of osmium or a highly radiogenic osmium component to the oceans. The overall trend for osmium and strontium could be explained by a regularly increasing input of global continental weathering sources but the Himalayas themselves appear not to be the dominant source.


Item Type:Article
Related URLs:
URLURL TypeDescription
http://dx.doi.org/10.1016/S0016-7037(99)00305-1DOIArticle
http://www.sciencedirect.com/science/article/pii/S0016703799003051PublisherArticle
ORCID:
AuthorORCID
Wasserburg, G. J.0000-0002-7957-8029
Additional Information:© 1999 Elsevier Science Ltd. Funding for this work was provided by a Max–Planck Postdoctoral Fellowship to M.S. We are grateful to G. Contin for collecting the sample of the Indus river in Pakistan. We thank K. Turekian and J. Edmond for giving critical comments. Caltech G.P.S. Contribution 8607 (1000). Work supported by DOE grant DE-FG03-88ER13851.
Funders:
Funding AgencyGrant Number
Max–Planck Postdoctoral FellowshipUNSPECIFIED
Department of Energy (DOE)DE-FG03-88ER13851
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Caltech Division of Geological and Planetary Sciences8607
Lunatic Asylum Lab1000
Issue or Number:23-24
Record Number:CaltechAUTHORS:20131119-140918131
Persistent URL:https://resolver.caltech.edu/CaltechAUTHORS:20131119-140918131
Official Citation:M. Sharma, G.J. Wasserburg, A.W. Hofmann, G.J. Chakrapani, Himalayan uplift and osmium isotopes in oceans and rivers, Geochimica et Cosmochimica Acta, Volume 63, Issues 23–24, December 1999, Pages 4005-4012, ISSN 0016-7037, http://dx.doi.org/10.1016/S0016-7037(99)00305-1. (http://www.sciencedirect.com/science/article/pii/S0016703799003051)
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:42579
Collection:CaltechAUTHORS
Deposited By: Ruth Sustaita
Deposited On:20 Nov 2013 21:19
Last Modified:09 Mar 2020 13:19

Repository Staff Only: item control page