The differentiation of the Skaergaard Intrusion

1987 ◽  
Vol 95 (4) ◽  
pp. 451-461 ◽  
Author(s):  
R. H. Hunter ◽  
R. S. J. Sparks
Keyword(s):  
Skaergaard Intrusion

The East Greenland continental margin, the Prinsen af Wales Bjerge and new Skaergaard intrusion initiatives

2001 ◽  
pp. 83-98
Author(s):  
Troels F.D. Nielsen ◽  
Henriette Hansen ◽  
C. Kent Brooks ◽  
Charles E. Lesher
Keyword(s):  
Continental Margin ◽  
Mineral Exploration ◽  
Science Research ◽  
Field Work ◽  
Alkaline Magmatism ◽  
Skaergaard Intrusion ◽  
East Greenland ◽  
Geological Processes ◽  
Break Up ◽  
Petroleum Company

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Nielsen, T. F., Hansen, H., Brooks, C. K., & Lesher, C. E. (2001). The East Greenland continental margin, the Prinsen af Wales Bjerge and new Skaergaard intrusion initiatives. Geology of Greenland Survey Bulletin, 189, 83-98. https://doi.org/10.34194/ggub.v189.5162 _______________ The rifted volcanic margin of East Greenland has remained a major area for field studies and the development of models for the dynamics of plume-related continental break-up since the start of the Danish Lithosphere Centre (DLC) in 1994. The studies cover a range of disciplines and geological processes from the early development of pre-break-up basin formation and sedimentation over the main phase of basaltic magmatism to the late stages of alkaline magmatism and structural re-equilibration. The East Greenland field activities in the summer of 2000, collectively referred to as EG 2000, were facilitated by a logistic platform provided by support from Statens Naturvidenskabelige Forskningsråd (SNF, the Danish Natural Science Research Council) and the Bureau of Minerals and Petroleum (BMP) in Nuuk, Greenland for the retrieval of 6 km of drillcore from the Skaergaard intrusion. During 1989 and 1990 mineral exploration had resulted in drilling of more than 15 km of core through the classic layered gabbros. The logistic platform also provided support for DLC and Geological Survey of Denmark and Greenland (GEUS) field work and projects throughout the Kangerlussuaq region and on the Blosseville Kyst (Fig. 1), as well as mineral exploration and petroleum company activities.

NIELSENITE, PdCu3, A NEW PLATINUM-GROUP INTERMETALLIC MINERAL SPECIES FROM THE SKAERGAARD INTRUSION, GREENLAND

2008 ◽  
Vol 46 (3) ◽  
pp. 709-716 ◽  
Author(s):  
A. M. McDonald ◽  
L. J. Cabri ◽  
N. S. Rudashevsky ◽  
C. J. Stanley ◽  
V. N. Rudashevsky ◽  
...  
Keyword(s):  
Mineral Species ◽  
Skaergaard Intrusion ◽  
Platinum Group

scholarly journals Parental magma of the Skaergaard intrusion: constraints from melt inclusions in primitive troctolite blocks and FG-1 dykes

2009 ◽  
Vol 159 (1) ◽  
pp. 61-79 ◽  
Author(s):  
Jakob K. Jakobsen ◽  
Christian Tegner ◽  
C. Kent Brooks ◽  
Adam J. R. Kent ◽  
Charles E. Lesher ◽  
...  
Keyword(s):  
Melt Inclusions ◽  
Parental Magma ◽  
Skaergaard Intrusion

scholarly journals Lateral Reactive Infiltration in a Vertical Gabbroic Crystal Mush, Skaergaard Intrusion, East Greenland

2013 ◽  
Vol 54 (5) ◽  
pp. 985-1016 ◽  
Author(s):  
Olivier Namur ◽  
Madeleine C. S. Humphreys ◽  
Marian B. Holness
Keyword(s):  
Crystal Mush ◽  
Skaergaard Intrusion ◽  
East Greenland ◽  
Reactive Infiltration

Bulk Liquid for the Skaergaard Intrusion and Its PGE-Au Mineralization: Composition, Correlation, Liquid Line of Descent, and Timing of Sulphide Saturation and Silicate–Silicate Immiscibility

2019 ◽  
Vol 60 (10) ◽  
pp. 1853-1880 ◽  
Author(s):  
Troels F D Nielsen ◽  
C Kent Brooks ◽  
Jakob K Keiding
Keyword(s):  
Precious Metal ◽  
Bulk Composition ◽  
Precious Metals ◽  
Bulk Liquid ◽  
Skaergaard Intrusion ◽  
Liquid Line ◽  
Multi Stage ◽  
Silicate Liquids ◽  
Crystallization Zone ◽  
Liquid Line Of Descent

Abstract Preferred and modelled bulk composition of the Skaergaard intrusion are compared to coeval basaltic compositions in East Greenland and found to relate to the second evolved cycle of Geikie Plateau Formation lavas and coeval Skaergaard-like dikes in major and trace element (Mg# ∼45, Ce/Nb ∼2·5, (Dy/Yb)N ∼1·35), and precious metal composition (Pd/Pt ∼3, Au/Pt ∼2) as well as in age (∼56 Ma). Successful comparisons of precious metal compositions only occur with Skaergaard models based on mass balance. The bulk liquid of the intrusion evolved along the liquid line of descent to immiscibility between Si- and Fe-rich silicate liquids after ∼90% of crystallization (F = ∼0·10) in agreement with experimental constraints. Immiscibility led to accumulation and fractionation of the Fe-rich silicate melt in the mushy floor of the intrusion and continued accumulation of granophyre component in the remaining bulk liquid. The composition of plagioclase in the precious metal mineralized gabbro and modelling of Pd/Pt and Au/Pt in first formed droplets of sulphide melt suggest that sulphide saturation was reached in interstitial melts in crystal mushes in the floor and roof and in bulk liquid with a composition equivalent to that of the bulk liquid at lower UZa times and after crystallization of 82–85% of the bulk liquid (F = 0·19–0·16). Prior to sulphide saturation in UZa type melt, the precious metals ratios of the bulk liquid were controlled by the loss of Pt relative to Pd and Au in agreement with the low empirical and experimental solubility of Pt of ∼9ppb compared to a much higher value for Pd and Au. The relative timing between sulphide saturation (F = ∼0·18) and immiscibility between silicate melts (F = ∼0·10) and modelled precious metal ratios underpin the proposed multi-stage model for the mineralization, advocating initial accumulation in the mushy floor of the magma chamber controlled by sulphide saturation in mush melts rather than bulk melt, followed by redistribution of precious metals in a macro-rhythmic succession of gabbroic layers of the upward migrating crystallization zone.

The origin of rhythmic layering

1978 ◽  
Vol 42 (323) ◽  
pp. 337-345 ◽  
Author(s):  
Sven Maaløe
Keyword(s):  
Crystal Size ◽  
Nucleation Theory ◽  
Skaergaard Intrusion

SummaryRhythmic layering in the Skaergaard intrusion shows variation in crystal size and in modal proportions of primocrysts with structural height. These changes are ascribed to variations in nucleation rates of primocrysts. The nucleation theory requires that crystallization occurs under supercooled conditions, and that the crystallization of one primocryst phase may change the composition of the magma in such a manner that the nucleation rates of other primocrysts are influenced. Both these constraints appear to have been fulfilled for the Skaergaard intrusion.

Sign in / Sign up

Export Citation Format

Share Document