Natural History and Cultural Background
2012. "Natural History and Cultural Background", Neoproterozoic Glacial and Associated Facies in the Tanafjord-Varangerfjord Area, Finnmark, North Norway, A.H.N. Rice, Marc B. Edwards, T.A. Hansen
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The vegetation in the excursion area varies between occasional wooded-tundra in sheltered low-lying areas and tundra in exposed and upland areas. Clitter, consisting of angular, up to meter-sized loose blocks of the directly underlying lithology, is typical of upland areas, especially where underlain by quartzites/sandstones.
The most common tree is the birch (Betula spp.). This can grow to several tens of meters high, although in windy areas, it is completely stunted, with no height, but a very thin “stem” (<1 cm) that may have a lateral extent of several meters. Pine trees (Pinus sylvestris) are rare because they have all been cut down, not because the conditions are too extreme. Willow (Salix spp.) and less often alder (Alnus sp.), poplar (Populus sp.), and rowan (Sorbus aucuparia) trees are also present. There are several species of Salix, but these produce a large array of hybrids, so identifying true “species” is extremely difficult. Low juniper bushes (Juniperus communis) occur on well-drained ground, frequently growing over deep holes between boulders; it is, therefore, dangerous to stand on.
On dry gritty slopes, especially below outcrops of the Nyborg and Mortensnes Formations on the north side of Varangerfjord, the unusual ferns Botrychium lunaria (Fig. 10A) and rarely Botrychium boreale grow. Nyserot (Veratrum album; Fig. 10B) is an extremely poisonous lily that is found only in the Tana-West Varangerfjord region and in the Alpine-Apennine-Carpathian region of Central Europe. In contrast, common scurvygrass (Cochlearia officinalis; Fig. 10C), which grows in salty
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Neoproterozoic Glacial and Associated Facies in the Tanafjord-Varangerfjord Area, Finnmark, North Norway
The Neoproterozoic glacial deposits of north Norway (snowball Earth Marinoan-aged Smalfjord and the younger Gaskiers-aged Mortensnes Formations) are superbly documented and illustrated in this comprehensive eight-day field guide. Lodgement, banded, deformation, flow, and melt-out diamictites derived from gneissic, clastic, and dolomitic sources are described, as well as glaciomarine, proglacial, and fluvioglacial sediments. Outcrops showing glaciotectonic folds, faults, flanking structures, shear-sense criteria (sigma-clasts), fluidized sediments, pro- and subglacial channels, iceberg dump structures, ghost clasts, dropstones, ice-crystal molds, and a ?kettle hole are included. The classic glacial striations at Oaibaccanjar'ga are described in detail. Marinoan cap dolostones overlying the Smalford Formation are included. In comparison to other Neoproterozoic glacial successions, this area is easily accessible by airplane and/or car, and most outcrops occur along the roadside or can be easily reached by small boat. This volume includes information about accommodations and small boat rental, and a fascinating summary of the natural and local history.