Quick
Search: 		  
advanced search
 GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help 
Geology Signup for GSW Email News
JOURNAL HOME HELP CONTACT PUBLISHER SUBSCRIBE ARCHIVE SEARCH TABLE OF CONTENTS
Geology; December, 2007; v. 35; no. 12; p. 1099-1102; DOI: 10.1130/G24022A.1
© 2007 Geological Society of America
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
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 Download to citation manager
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Simmons, S. F.
Right arrow Articles by Brown, K. L.
Right arrow Search for Related Content
GeoRef
Right arrow GeoRef Citation

The flux of gold and related metals through a volcanic arc, Taupo Volcanic Zone, New Zealand

Stuart F. Simmons*,1 and Kevin L. Brown*,2

1 School of Geography, Geology and Environmental Science, University of Auckland, Private Bag 92019, Auckland Mail Centre, Auckland 1142, New Zealand
2 GEOKEM, P.O. Box 95-210, Swanson, Waitakere 0653, New Zealand

We determined the concentrations of gold, silver, arsenic, antimony, and mercury in deep hydrothermal solutions (~1 km depth, 200 to >300 °C) from six geothermal systems and calculated their fluxes for a 250-km-long segment of volcanic arc in the Taupo Volcanic Zone, New Zealand. The three orders of variation in the concentrations (<0.1–23 ppb Au; 2.7–2400 ppb Ag) and fluxes of precious metals across the arc indicate that the supply of metals in deep hydrothermal solutions is influenced by the intrusion of andesitic and basaltic magmas, which also govern the convective heat transfer and flux of metals. Two of the geothermal systems, Rotokawa and Mokai, have the highest hydrothermal fluxes of gold and/or silver known, and can supply enough metal in ~50,000 yr or less to match the inventories of the largest hydrothermal ore deposits in the world; although, so far, no ore mineralization has been found in these systems. If the huge amounts of hydrothermal precious metals (minimum values range 80–163 kg Au/yr and 6800–13,850 kg Ag/yr) that flow through the Taupo Volcanic Zone are representative of all arcs throughout time, then focused fluid flow and efficient metal deposition are the most important processes governing the formation of gold and silver ore deposits.

Key Words: gold • silver • hydrothermal • volcanic arcs • metal fluxes






JOURNAL HOME HELP CONTACT PUBLISHER SUBSCRIBE ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2009 by Geological Society of America