The origin of high-Cu/S sulfides by shallow-level degassing in the Skaergaard intrusion, East Greenland
Journal Article (Journal Article)
The Skaergaard intrusion of East Greenland is characterized by unusually low sulfur (S) and high metal/S ratios. Explanations range from S lost during cooling to suggestions that low S was characteristic of the original magma. A nonequilibrium thermodynamic analysis of modal variations in the chilled margin and Lower Zone is consistent with a late stage reaction of chalcopyrite → magnetite ± bornite + Slost; the pre-reaction assemblage was dominated by chalcopyrite with a Cu:S mass ratio ~1:1, a ratio unusually low for an undegassed hotspot basalt. A comparison with other hotspot and flood basalt provinces suggests that these magmas can lose significant S to recirculating shallow-level degassed magma. It is concluded that degassing of the parent Skaergaard magma prior to solidification and continuous vapor loss during crystallization both contributed to the overall high metal/S ratios of the Skaergaard system.
Full Text
Duke Authors
Cited Authors
- Li, C; Boudreau, AE
Published Date
- December 1, 2017
Published In
Volume / Issue
- 45 / 12
Start / End Page
- 1075 - 1078
Electronic International Standard Serial Number (EISSN)
- 1943-2682
International Standard Serial Number (ISSN)
- 0091-7613
Digital Object Identifier (DOI)
- 10.1130/G39540.1
Citation Source
- Scopus