CaltechAUTHORS
  A Caltech Library Service

Geochemistry of Precambrian carbonates: V. Late Paleoproterozoic seawater

Veizer, Ján and Plumb, K. A. and Clayton, R. N. and Hinton, R. W. and Grotzinger, J. P. (1992) Geochemistry of Precambrian carbonates: V. Late Paleoproterozoic seawater. Geochimica et Cosmochimica Acta, 56 (6). pp. 2487-2501. ISSN 0016-7037. https://resolver.caltech.edu/CaltechAUTHORS:20141008-113453669

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:20141008-113453669

Abstract

In an effort to obtain better constrained data for the first- and second-order variations in the isotopic composition of late Paleoproterozoic (1.8 ± 0.2 Ga) seawater, we report a study of mineralogy, chemistry, and isotopic composition of the Coronation Supergroup (~1.9 Ga, NWT), Canada, and the McArthur Group (~1.65 Ga, NT), Australia. Petrologically, both carbonate sequences are mostly dolostones. The McArthur population, however, contains more abundant textural features that attest to the former presence of sulfates and halite, and the facies investigated herein probably represent ancient equivalents of modern evaporitic sabkhas and lacustrine playa lakes. This is reflected in ^(18)O enrichment (up to −2.9%. PDB) and high Mn, Fe, and Sr concentrations. Nonetheless, the available Δ^(18)O data indicate that the “best estimate” for the Archean to late Paleoproterozoic limestones is about −7%. PDB, with dolostones some 3 ± 2%. heavier. The observed Δ^(18)O_doiomitc-calcite is thus within the range of the proposed fractionation factor for a cogenetic mineral pair. This, together with the consistency of isotopic patterns for sedimentological facies over almost 2 billion years, from the late Paleoproterozoic to the present, suggest that dolomitization was an early diagenetic event and that the ^(18)O depletion of the Archean to late Paleoproterozoic carbonates is not an artefact ofpost-depositional alteration. The δ^(13)C, although within the range of other Precambrian and Phanerozoic carbonates, indicates a possible secular evolution from 0 ± 2%. PDB at 1.9 Ga ago to −1 ± 1.5%. at 1.65 Ga ago. The secular evolution for reflects the ^(87)Sr increase from 0.7031 ± 0.0008 at 3.5 ± 0.1 Ga ago, through 0.7025 ± 0.0015 at 2.8 ± 0.2 Ga, 0.7033 at 2.5 Ga, 0.7050 at 2.25 ± 0.25 Ga, 0.7047 at 1.91, to ≤0.706 at 1.65 Ga ago.


Item Type:Article
Related URLs:
URLURL TypeDescription
http://dx.doi.org/10.1016/0016-7037(92)90204-VDOIArticle
http://www.sciencedirect.com/science/article/pii/001670379290204VPublisherArticle
ORCID:
AuthorORCID
Grotzinger, J. P.0000-0001-9324-1257
Additional Information:© 1992 Pergamon Press Ltd. Received May 10, 1991; accepted in revised form March 25, 1992. This work has been supported financially by the NSF (Grant No. EAR-831 3579 to Jan Veizer, R. N. Clayton, and Abraham Lerman at the time of Veizer’s stay at the Department of Geological Sciences, Northwestern University, Evanston, Illinois) and in the final stages by the Natural Sciences and Engineering Research Council of Canada and Canada Council (Killam Research Fellowship to JV). R. W. Hinton acknowledges the support by NASA (grant NAG 9-5 1 to RNC). K. Bell and J. Blenkinsop provided access to solid source mass spectrometer, J. M. Oly carried out isotope analysis for K. A. Plumb in the Bureau of Mineral Resources stable isotope laboratory. We acknowledge technical support of W. Schmiedel and A. Sodonis, typing of the manuscript by B. Kemper, drafting of figures by W. Malcherek, photography by M. Ress, provision of samples by the Northern Territory Geological Survey and logistic advice by N. Williams. K. A. Plumb publishes with the permission of the Director, Bureau of Mineral Resources, Geology and Geophysics. Constructive reviews of D. R. Lowe, B. E. Taylor, D. F. Williams, S.-S. Sun, and an anonymous reviewer have been appreciated.
Funders:
Funding AgencyGrant Number
NSFEAR-831 3579
Natural Sciences and Engineering Research Council of Canada (NSERC)UNSPECIFIED
Canada Council Killam Research FellowshipUNSPECIFIED
NASANAG 9-51
Issue or Number:6
Record Number:CaltechAUTHORS:20141008-113453669
Persistent URL:https://resolver.caltech.edu/CaltechAUTHORS:20141008-113453669
Official Citation:Veizer, J., Plumb, K. A., Clayton, R. N., Hinton, R. W., & Grotzinger, J. P. (1992). Geochemistry of Precambrian carbonates: V. Late Paleoproterozoic seawater. Geochimica et Cosmochimica Acta, 56(6), 2487-2501. doi: http://dx.doi.org/10.1016/0016-7037(92)90204-V
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:50270
Collection:CaltechAUTHORS
Deposited By: Jason Perez
Deposited On:08 Oct 2014 23:11
Last Modified:03 Oct 2019 07:21

Repository Staff Only: item control page