Composition and provenance of the Lilljeborgfjellet Conglomerate Haakon VII Land, Spitsbergen

[摘要] The Siktefjellet Group of late Silurian or early Devonian age, consisting of the Lilljeborgfjellet Conglomerate and the overlying Siktefjellet Sandstone, is generally accepted as the oldest part of the Old Red Sandstone in Spitsbergen. Most of the clasts of the conglomerate are only slightly rounded and consist of lithologies typical for the underlying basement. A minor component of quartz porphyry clasts is present; these are well-rounded, indicating a longer transport. The provenance of the quartz porphyry clasts is discussed in relation to the known outcrops of quartz porphyry in Svalbard, one occurring in the neighbourhood of the conglomerate, the other ones far away. The quartz porphyry in close proximity is younger than the Lilljeborgfjellet Conglomerate and therefore not a possible source rock. A close petrographic and geochemical comparison with the quartz porphyries at three localities in Nordaustlandet (150-200 km in easterly direction and of probable Grenvillian age) is presented showing many s...

[学科分类] 自然科学（综合）