Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Bolhar, R. Articles by Hergt, J. M. Search for Related Content GeoRef GeoRef Citation

Continental setting inferred for emplacement of the 2.9–2.7 Ga Belingwe Greenstone Belt, Zimbabwe

¹ School of Earth Sciences, University of Melbourne, Melbourne, Victoria 3010, Australia

New major element, trace element, and Nd isotope data are reported for volcanic rocks from the 2.9 Ga Lower Greenstone and 2.7 Ga Upper Greenstone assemblages of the Belingwe Greenstone Belt. The majority of samples from five distinct stratigraphic units have generally unfractionated to slightly depleted trace element patterns similar to those observed in the small number of previous studies. However, previously unrecognized incompatible element–enriched samples with distinct high field strength anomalies invariably also occur in close association. These are reminiscent of crustally contaminated rocks from other well-documented greenstone settings. Numerical modeling of combined assimilation-fractionation processes using both trace and major elements suggests 10%–30% incorporation of model Archean continental crust in their genesis, in accord with Nd isotope compositions. These new observations are not consistent with a mid-ocean-ridge or oceanic plateau–type setting for Belingwe Greenstone Belt volcanism, but instead favor a model in which melts interacted with preexisting continental crust.

Key Words: Archean • Belingwe Greenstone Belt • crustal contamination • komatiite • Zimbabwe craton

This article has been cited by other articles:

				K. SHIMIZU, E. NAKAMURA, and S. MARUYAMA The Geochemistry of Ultramafic to Mafic Volcanics from the Belingwe Greenstone Belt, Zimbabwe: Magmatism in an Archean Continental Large Igneous Province J. Petrology, November 1, 2005; 46(11): 2367 - 2394. [Abstract] [Full Text] [PDF]

				K. Shimizu, E. Nakamura, K. Kobayashi, and S. Maruyama Discovery of Archean continental and mantle fragments inferred from xenocrysts in komatiites, the Belingwe greenstone belt, Zimbabwe Geology, April 1, 2004; 32(4): 285 - 288. [Abstract] [Full Text] [PDF]

				A. Hofmann and P. H.G.M. Dirks Continental setting inferred for emplacement of the 2.9-2.7 Ga Belingwe Greenstone Belt, Zimbabwe: Comment and Reply Geology, June 1, 2003; 31(6): e30 - e31. [Full Text] [PDF]

				R. Bolhar, J. D. Woodhead, and J. M. Hergt REPLY Geology, June 1, 2003; 31(6): e31 - e31. [Full Text] [PDF]

				A. Hofmann and P. H.G.M. Dirks Continental setting inferred for emplacement of the 2.9-2.7 Ga Belingwe Greenstone Belt, Zimbabwe: Comment and Reply: COMMENT Geology, January 1, 2003; 31(1): e30 - e31. [Full Text] [PDF]

				R. Bolhar, J. D. Woodhead, and J. M. Hergt Continental setting inferred for emplacement of the 2.9-2.7 Ga Belingwe Greenstone Belt, Zimbabwe: Comment and Reply: REPLY Geology, January 1, 2003; 31(1): e31 - e31. [Full Text] [PDF]