Skip Navigation

This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by RONALD FROST, B.
Right arrow Articles by SWAPP, S. M.
Right arrow Search for Related Content
GeoRef
Right arrow GeoRef Citation
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Journal of Petrology Volume 41 Number 12 Pages 1759-1776 2000
© Oxford University Press 2000

Origin of the Charnockites of the Louis Lake Batholith, Wind River Range, Wyoming

B. RONALD FROST,*, CAROL D. FROST, THOMAS P. HULSEBOSCH,{dagger} and SUSAN M. SWAPP

DEPARTMENT OF GEOLOGY AND GEOPHYSICS, UNIVERSITY OF WYOMING, LARAMIE, WY 82071, USA

The 2·63 Ga Louis Lake batholith, a calc-alkalic pluton exposed in Wind River Range of western Wyoming, consists of minor diorite, quartz diorite, granodiorite, and granite. At shallow structural levels the batholith is pyroxene free, but at deeper levels, all units of the batholith contain pyroxenes. On its northern margin the batholith was emplaced at P = 5–6 kbar, T = 775–800°C, fO2 at FMQ (fayalite–magnetite–quartz) + 1·5 to FMQ + 1·8, and aH2O ~0·1. Along the southern margin of the batholith the emplacement pressure was ~3 kbar. The batholith includes two compositional series. The peraluminous high-REE series is rich in K2O, and displays larger FeOt/(FeOt + MgO). The metaluminous low-REE series has less K2O and smaller FeOt/(FeOt + MgO). In the Boulder Canyon area, most of the rocks belong to the low-REE series. The Nd, Pb, and Sr initial isotopic compositions of both series vary and do not correlate with SiO2 abundance. Relatively constant Fe/Mg ratios over a wide range of SiO2 and the large variation in initial isotopic compositions indicate that the sources for the Louis Lake batholith include older Wyoming province crust- and mantle-derived mafic melts. The calc-alkalic nature of the Boulder Canyon charnockites indicates that there is no special C-type magma. Instead, charnockites will form in any rock type, if the water activity is low enough.

KEY WORDS: Archean geology; charnockite; granite; Wind River Range; Wyoming province


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 Bulletin de la Societe Geologique de FranceHome page
A. Pouclet, R. Tchameni, K. Mezger, M. Vidal, E. Nsifa, C. Shang, and J. Penaye
Archaean crustal accretion at the northern border of the Congo Craton (South Cameroon). The charnockite-TTG link
Bulletin de la Societe Geologique de France, September 1, 2007; 178(5): 331 - 342.
[Abstract] [Full Text] [PDF]

Home page
 J PetrologyHome page
J. A. PERCIVAL and J. K. MORTENSEN
Water-deficient Calc-alkaline Plutonic Rocks of Northeastern Superior Province, Canada: Significance of Charnockitic Magmatism
J. Petrology, September 1, 2002; 43(9): 1617 - 1650.
[Abstract] [Full Text] [PDF]

Home page
 J PetrologyHome page
B. R. FROST, C. G. BARNES, W. J. COLLINS, R. J. ARCULUS, D. J. ELLIS, and C. D. FROST
A Geochemical Classification for Granitic Rocks
J. Petrology, November 1, 2001; 42(11): 2033 - 2048.
[Abstract] [Full Text] [PDF]


Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.