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Geochemistry of Precambrian carbonates - 3-shelf seas and non-marine environments of the ArcheanSamples from the Pangola and Ventersdorp Supergroups (Kaapvaal Craton, South Africa) and from the Fortescue and Hamersley Groups (Pilbara Block, Australia) were analyzed, using XRF, AAS, and isotope-analysis techniques to investigate the mineralogical, chemical, and isotopic features of these representatives of contemporary shelf carbonates (Pangola and Hamersley samples) and nonmarine carbonates (the Ventersdorp and Fortescue samples). Results show that, mineralogically, the shelf carbonates are almost exclusively dolostones, while the lacustrine facies are predominantly limestones. Geological, trace-element, and oxygen-isotope results of the shelf carbonates suggest that their original mineralogy may have been aragonite, and that the Pangola dolostones may represent a direct dolomitization product of this precursor. By contrast, the stabilization of the Hamersley carbonates may have involved an additional step of transformation of a metastable precursor into limestone.
Document ID
19910027995
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Veizer, Jan
(Ottawa, University Canada; Bochum, Ruhr-Universitaet, Federal Republic of Germany, United States)
Clayton, R. N.
(Chicago, University IL, United States)
Hinton, R. W.
(Chicago, University IL; Grant Institute of Geology, Edinburgh, United Kingdom)
Von Brunn, Victor
(Natal, University Pietermaritzburg, Republic of South Africa, United States)
Mason, T. R.
(Natal, University Durban, Republic of South Africa, United States)
Date Acquired
August 14, 2013
Publication Date
October 1, 1990
Publication Information
Publication: Geochimica et Cosmochimica Acta
Volume: 54
ISSN: 0016-7037
Subject Category
Geophysics
Accession Number
91A12618
Funding Number(s)
CONTRACT_GRANT: NAG9-51
CONTRACT_GRANT: NSF EAR-83-13579
Distribution Limits
Public
Copyright
Other

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