Table 16.1.

Radiometric age data in the Median segment, Idefjorden terrane, modified after the geochronological database at the Geological Survey of Sweden

LithologyN_SWEREFE_SWEREFIsotope systemMethodMineralAge typeAge ± 2σ (Ma)Age interpretationReference
Mylonite641115034699540Ar–39ArUV-laserBiotitePlateau861 ± 10*DeformationViola et al. (2011)
Mylonite641115034699540Ar–39ArUV-laserMuscovitePlateau870 ± 4*DeformationViola et al. (2011)
Amphibolite636727232905240Ar–39ArStep-wise heatingHornblendePlateau910 ± 6Metamorphic or coolingPage et al. (1996a)
Mafic layer635806032798440Ar–39ArStep-wise heatingHornblendePlateau911 ± 5Metamorphic or coolingPage et al. (1996a)
Mylonite641115034699540Ar–39ArUV-laserMuscovitePlateau913 ± 8DeformationViola et al. (2011)
Metagabbro636568534728340Ar–39ArStep-wise heatingHornblendePlateau914 ± 6Metamorphic or coolingPage et al. (1996a)
Lamprophyre657282138929640Ar–39ArStep-wise heatingBiotitePlateau915 ± 1MagmaticWahlgren et al. (2015)
Pegmatite658612733436840Ar–39ArStep-wise heatingMuscovitePlateau915 ± 3MagmaticBingen et al. (2006)
Amphibolite635646932865340Ar–39ArStep-wise heatingHornblendePlateau915 ± 5Metamorphic or coolingPage et al. (1996a)
Garnet amphibolite634266932796740Ar–39ArStep-wise heatingHornblendePlateau915 ± 6Metamorphic or coolingPage et al. (1996a)
Amphibolite634317932886040Ar–39ArStep-wise heatingHornblendePlateau916 ± 8Metamorphic or coolingPage et al. (1996a)
Granitic vein6412216339383U–PbSIMSZirconConcordia917 ± 13MagmaticScherstén et al. (2004)
Amphibolite6342779328865U–PbID-TIMSTitanite207Pb/206Pb917 ± 14Metamorphic or coolingJohansson & Johansson (1993)
Amphibolite635960932371840Ar–39ArStep-wise heatingHornblendePlateau918 ± 6Metamorphic or coolingPage et al. (1996a)
Mylonite641115034699540Ar–39ArUV-laserBiotitePlateau923 ± 82DeformationViola et al. (2011)
Migmatitic granite6339725332599U–PbSIMSZirconWeighted average 207Pb/206Pb968 ± 13MetamorphicAndersson et al. (2002)
Migmatitic banded gneiss6377259354042U–PbSIMSZirconWeighted average 207Pb/206Pb969 ± 13MetamorphicAndersson et al. (2002)
Granitic orthogneiss6623566365323U–PbSIMSZirconUpper intercept971 ± 8MetamorphicLarson et al. (1999)
Stromatic orthogneiss6346246326175U–PbSIMSZirconWeighted average 207Pb/206Pb980 ± 13MetamorphicAndersson et al. (2002)
Pegmatite6469566333700U–PbID-TIMSColumbiteUpper intercept984 ± 6MagmaticRomer & Smeds (1996)
Orthogneiss§664691437018640Ar–39ArStep-wise heatingMuscovitePlateau999 ± 6CoolingPage et al. (1996b)
Granitic gneiss6396624326776U–PbSIMSZirconConcordia1017 ± 7MetamorphicAustin Hegardt & Cornell (2010)
Mafic high-pressure and -temperature granulite, metadolerite6462090347270U–PbID-TIMSZirconConcordia1026 ± 5MetamorphicSöderlund et al. (2008)
Mafic high-pressure and -temperature granulite, metadolerite6462090347270Lu-HfID-TIMSMulti-mineralIsochron1027 ± 9MetamorphicSöderlund et al. (2008)
Pegmatite6410690320412U–PbSIMSZirconUpper intercept1043 ± 11MagmaticAustin Hegardt et al. (2007)
Mafic high-pressure and -temperature granulite, metadolerite6464052348098U–PbN-TIMSZirconUpper intercept1046 ± 6MetamorphicSöderlund et al. (2008)
Granite6463524344137U–PbSIMSZirconConcordia1304 ± 6MagmaticAustin Hegardt et al. (2007)
Granite6411647321000U–PbSIMSZirconUpper intercept1311 ± 8MagmaticAustin Hegardt et al. (2007)
Granite6480971343179U–PbID-TIMSZirconNo information1319 ± 6MagmaticPiontek et al. (1998) (abstract)
Granite6488441336100U–PbID-TIMSZirconNo information1334 ± 7MagmaticPiontek et al. (1998) (abstract)
Granite6384636323787U–PbSIMSZirconWeighted average 207Pb/206Pb1343 ± 7MagmaticPetersson et al. (2015)
Granite6623422337040U–PbID-TIMSTitaniteWeighted average 207Pb/206Pb1554 ± 2CoolingÅhäll & Connelly (2008)
Granodiorite6395171339087U–PbSIMSZirconUpper intercept1558 ± 10MagmaticÅhäll & Connelly (2008)
Granite6623422337040U–PbID-TIMSZirconUpper intercept1561 ± 2MagmaticÅhäll & Connelly (2008)
Granodiorite6593204383583U–PbSIMSZirconWeighted average 207Pb/206Pb1568 ± 8MagmaticPetersson et al. (2015)
Granodiorite6365982347029U–PbSIMSZirconUpper intercept1578 ± 7MagmaticÅhäll & Connelly (2008)
Tonalite6363573346158U–PbID-TIMSZircon207Pb/206Pb1584 ± 15MagmaticÅhäll et al. (1995)
Felsic net-vein6397294324270U–PbSIMSZirconConcordia1585 ± 4MagmaticAhlin et al. (2006)
Stromatic orthogneiss6346246326175U–PbSIMSZirconWeighted average 207Pb/206Pb1585 ± 11MagmaticAndersson et al. (2002)
Veined granitic gneiss6391284331537U–PbSIMSZirconConcordia1590 ± 12MagmaticAustin Hegardt & Cornell (2010)
Granitic orthogneiss6623566365323U–PbSIMSZirconWeighted average 207Pb/206Pb1590 ± 14MagmaticLarson et al. (1999)
Granodiorite6600445321428U–PbID-TIMSZirconUpper intercept1594 ± 7MagmaticÅhäll & Connelly (2008)
Quartz monzodioritic orthogneiss6623566365323U–PbSIMSZirconWeighted average 207Pb/206Pb1596 ± 11MagmaticLarson et al. (1999)
Veined granitic gneiss6396624326776U–PbSIMSZirconConcordia1598 ± 9MagmaticAustin Hegardt & Cornell (2010)
Granodiorite6550336368010U–PbSIMSZirconUpper intercept1599 ± 5MagmaticÅhäll & Connelly (2008)
Granitic gneiss6365687333486U–PbSIMSZirconWeighted average 207Pb/206Pb1600 ± 15MagmaticPetersson et al. (2015)
Tonalite6474223372024U–PbSIMSZirconUpper intercept1602 ± 10MagmaticÅhäll & Connelly (2008)
Gneiss6412216339383U–PbSIMSZirconWeighted average 207Pb/206Pb1605 ± 10MagmaticScherstén et al. (2004)
Orthogneiss6396574322579U–PbSIMSZirconUpper intercept1605 ± 9MagmaticÅhäll & Connelly (2008)
Tonalite6596312400937U–PbID-TIMSZirconNot known1607 ± 4MagmaticÅhäll & Connelly (2008)
Migmatitic augen gneiss6619093391964U–PbID-TIMSZirconUpper intercept1608 ± 4MagmaticÅhäll & Connelly (2008)
Rhyolite6533353363572U–PbSIMSZirconConcordia1610 ± 6MagmaticSGU unpublished data
Granodiorite, K-feldspar porphyric6542856358904U–PbSIMSZirconWeighted average 207Pb/206Pb1611 ± 6MagmaticSGU unpublished data
Augen granite gneiss6396500333174U–PbSIMSZirconConcordia1614 ± 5MagmaticAhlin et al. (2006)
Felsic volcanic rock6538679362753U–PbID-TIMSZirconUpper intercept1614 ± 7MagmaticLundqvist & Skiöld (1993)
Veined granitic gneiss6393310329614U–PbSIMSZirconConcordia1616 ± 10MagmaticAustin Hegardt & Cornell (2010)
Gneissic granite6450579358125U–PbSIMSZirconConcordia1616 ± 9MagmaticHellström et al. (2007a)
Migmatitic granitic augen gneiss6398789323952U–PbSIMSZirconUpper intercept1618 ± 7MagmaticAhlin et al. (2006)
Dacite6538679362753U–PbID-TIMSZirconUpper intercept1619 ± 5MagmaticÅhäll & Connelly (2008)
Sub-volcanic granite6532158362950U–PbSIMSZirconWeighted average 207Pb/206Pb1621 ± 7MagmaticSGU unpublished data
Granitic vein6410593339952U–PbSIMSZircon207Pb/206Pb1624 ± 6MagmaticScherstén et al. (2000)
Megacrystic granitic gneiss6509274341668U–PbSIMSZirconWeighted average 207Pb/206Pb1624 ± 6MagmaticPetersson et al. (2015)
Tonalite6569865383665U–PbSIMSZirconWeighted average 207Pb/206Pb1628 ± 7MagmaticPetersson et al. (2015)
K-feldspar phyric rhyolite6513570344366U–PbID-TIMSZirconUpper intercept1631 ± 3MagmaticÅhäll & Connelly (2008)
Monzogranite, augen-bearing6501963343104U–PbSIMSZirconWeighted average 207Pb/206Pb1631 ± 4MagmaticSGU unpublished data
Granite6509337341418U–PbID-TIMSZirconUpper intercept1634 ± 3MagmaticÅhäll & Connelly (2008)
Gneiss6410871339700U–PbSIMSZirconWeighted average 207Pb/206Pb1640 ± 9MagmaticPetersson et al. (2015)
Metadacite6365985347329U–PbID-TIMSZirconUpper intercept1659 ± 9MagmaticÅhäll & Connelly (2008)
  • *Minimum value.

  • Maximum value.

  • Sample from the Eastern Segment inside the Mylonite Zone.

  • §Sample from the Eastern Segment inside a strike-slip duplex related to the Mylonite Zone.

  • Detrital zircon U–Pb ages (Scherstén et al. 2000; Åhäll & Connelly 2008; Petersson et al. 2015) are not tabulated here but are discussed in the text. Geographical coordinates are given in the National SWEREF 99 TM coordinate system.

  • ID-TIMS, isotope dilution thermal ionization mass spectrometry; N-TIMS, Negative Thermal Ionization Mass Spectrometry; SIMS, secondary ion mass spectrometry.