Table 1.

Fission-track results from basement rocks of the Gjelsvikfjella and the western Mühlig–Hofmann Mountains

Sample LocationElev. (m) MineralNo of grains Rock type(Ns) ρs (×105 cm−2)(Ni) ρi (×105 cm−2)(Nd) ρd (×105 cm−2)P2) (%)Fission-track age±1σ (Ma)Mean track length ±1σ (µm) SD (µm) (No.)Mean Dpar (µm)±SD (No.)
8.1/2206017806592661446320±211.39±0.21
HochlinfjelletApatiteIntermed. dyke16.4312.0714.35(85)
8.1/519002035562616661418316±1411.91±0.221.60±0.23
HochlinfjelletApatiteIntermed. dyke47.8035.1614.342.18 (98)(396)
10.1/12060171527107566144334±2012.49±0.191.68±0.41
HochlinfjelletApatiteMafic dyke25.2717.7914.341.94 (100)(385)
13.1/22000935726661495300±1711.96±0.281.58±0.21
HochlinfjelletApatiteMigmatic gneiss8.296.4414.342.06 (54)(96)
17.1/1180013793680661418273±2211.71±0.291.54±0.20
FestningaApatiteMigmatite15.0112.8714.342.27 (60)(65)
18.1/115001824481518661436366±1611.98±0.191.61±0.20
FestningaApatiteLeucosome35.5922.0714.341.90 (100)(390)
3.1/115202011231222661453216±111.52±0.26
RisemedetApatiteAugen gneiss13.8315.0514.35(99)
14.12/415009558472661430277±2011.77±0.291.64±0.25
RisemedetApatiteMafic dyke30.5725.8614.352.26 (63)(47)
15.12/115001481191366142215±1612.92±0.181.80±0.25
RisemedetApatiteAugen gneiss25.8929.1514.361.77 (100)(370)
18.12/515001618642356661420186±91.75±0.22
RisemedetApatiteIntermed. gneiss31.1739.3914.36(86)
24.12/415001613141475661437208±1112.67±0.21.61±0.20
RisemedetApatiteAugen gneiss36.7923.6714.351.82 (85)(335)
31.12/21570181104137366140195±141.57±0.23
GygraApatiteGranite dyke17.5021.7714.35(100)
5.1/2145520599659661418216±161.59±0.23
JutulsessenApatiteGabbro8.269.0914.35(95)
18.1/21500121148271159143516±50
FestningaTitanite?40.529.5621.16
14.12/415001410443801591410342±30
RiesemedetTitaniteMafic dyke38.0113.8421.11
24.12/215001312694391591432367±23
RisemedetTitaniteAugen gneiss112.9339.0721.05
5.1/21455187673011591440323±25
JutulsessenTitaniteGabbro13.545.3121.22
  • Apatite (titanite) fission-track ages were calculated using an IRMM-540 (CN2) dosimeter glasses with a zeta value for B. Emmel of ζIRMM-540=333±9 (ζCN2=124±3.25). Fission-track ages are reported as central ages.

  • Elev., elevation; ρs, ρi, ρd, Ns, Ni, Nd, density and number of counted spontaneous, induced and dosimeter glass tracks; P2), chi-square probability.