Most of the differentiation related to the building of the Sveconorwegian Farsund intrusion occured in the lower crust

Conference (2010)

Sveconorwegian (Grenvillian) Massif type anorthosites and related granitoids result from postcollisional remelting of a continental arc root

in EOS : Transactions, American Geophysical Union (2009), 90(52), 11-02

A-type magmatic suites as tracers of the lower crust

in AGC/GAC – AMC/MAC – SEG – SGA Abstract Volume (2008), 33

Molybdenite Re-Os dating constrains gravitational collapse of the Sveconorwegian orogen, SW Scandinavia

in Lithos (2006), 87(3-4), 328-346

Inefficiency of magma mixing and source heterogeneity in the genesis of granitoids: the example of the Farsund body (southern Norway)

in Geophysical Research Abstracts (2005), 7

Derivation of the 1.0-0.9 Ga ferro-potassic A-type granitoids of southern Norway by extreme differentiation from basic magmas

in Precambrian Research (2003), 124

Major and trace elements, Sr and Nd isotopic data as well as mineral compositions are presented for a selection of the 1.0 - 0.9 ferro-potassic A-type granitoids (Bessefjellet, Rustfjellet ... [more ▼]

Major and trace elements, Sr and Nd isotopic data as well as mineral compositions are presented for a selection of the 1.0 - 0.9 ferro-potassic A-type granitoids (Bessefjellet, Rustfjellet, Verhuskjerringi, Valle, Holum, Svöfjell, Handeland-Tveit, Åseral, Lyngdal gabbronorites) that occur close to the Mandal-Ustaoset Line of southern Norway. These hornblende biotite granitoids (HBG) define an extensive differentiation trend ranging from gabbronorites (50 wt % SiO2) to granites (77 wt % SiO2). This trend is interpreted as resulting from extreme fractional crystallization of several basaltic magma batches with similar major and trace elements compositions. At 930 Ma, the HBG suite displays a narrower range in ISr (0.7027 - 0.7056) than in Nd(t) (+1.97 down to -4.90) suggesting some assimilation of a Rb-depleted lower crust (AFC process) or/and source variability. An age of 929 ± 47 Ma is given by a Rb-Sr isochron on the Holum granite (Sri = 0.7046 ±0.0006, MSWD = 1.7). Geothermobarometers indicate a low pressure of emplacement (1.3-2.7 kbar) and an oxygen fugacity close to NNO. High liquidus temperatures are given by the apatite saturation thermometer (1005°C to 1054 °C) and are in agreement with results from other studies. The basaltic parent magmas of the HBG suite are partial melts of an hydrous mafic, potassic source lying either in the lithospheric upper mantle or in the mafic lower crust derived from it. This contrasts with the 930 Ma anorthosite-mangerite-charnockite suite (AMC) of the Rogaland Province for which a depleted lower crustal anhydrous gabbronoritic source has been indicated. The present data imply the penecontemporaneous melting of two contrasting sources in southern Norway. The source duality could result from an increasing degree of metamorphism (amphibolite to granulite) from East to West, an horizontal stratification of the lower crust or from the stratification of the lithosphere (melting of the lower crust or upper mantle). It may also indicate that the AMC and HBG suites formed in two distinct crustal segments. The linear alignment of the HBG suite along the Mandal-Ustaoset shear zone suggests that a linear uprise of the asthenosphere, following a lithospheric delamination under this structure, could be the vector of the mantle heat. [less ▲]

Petrology of the Lyngdal granodiorite (southern Norway) and the role of fractional crystallization in the genesis of Proterozoic rapakivi-like granites

in Precambrian Research (2003), 124(2-4), 149-184

Phase equilibria and P-T-fH2O-fO2 crystallization conditions of the Lyngdal granodiorite (southern Norway) and the origin of A-type granites in anorthosite complexes

in Journal of Conference Abstracts (2002), 7(1), 15

Experimental determination of phase equilibria of the Lyngdal granodiorite (southern Norway)

in Journal of Conference Abstracts (2001), 6