Rocks formed in these two periods do not easily divide at their mutual boundary and it is convenient to treat them together. In doing so we are addressing perhaps the best known and most conspicuous formations of Svalbard. Few geologists have been to the archipelago without noticing fossils and making some observations on these rocks. We are therefore embarking on a substantial study. A three-fold division of Paleozoic rocks in Svalbard is convenient in which Silurian and Devonian or middle Paleozoic history, dominated by Caledonian events, is followed by a Late Paleozoic interval of increasingly stable conditions which show little impact from Variscan, Ellesmerian or Uralian events elsewhere. This contrast applies conspicuously in Permian western Arctic regions.The Carboniferous-Permian outcrops are shown on Fig. 17.1. These rocks are the lower element in the Post-Devonian cover sequence divided between the Spitsbergen Basin and the Eastern Platform and Bjørnøya.The outcrops are disposed in two main areas in Spitsbergen and one in Bjørnøya. The Spitsbergen Basin was at first divided into troughs by inherited N-S faults. These then coalesced and extended throughout Spitsbergen.The present outcrop pattern resulted (i) from Late Cretaceous tilting with loss by erosion to the north, burial to the south and wide E-W exposure across the middle.(ii) A linear belt along the west coast, brought to the surface by folding and uplift along the Cenozoic West Spitsbergen Orogenic Belt from Kongsfjorden to Hornsund. Outcrops are frequently controlled by overthrusting from the west.(iii) The Bjørnøya Carboniferous outcrop

The Triassic Period of about 40 million years dutation spanned about a third of that of the Carboniferous and Permian interval. The Triassic rocks of Svalbard are easily distinguished from the underlying Permian strata because of a distinct desconformity between them and a marked contrast in facies from the resistant. pale coloured, cherls and siliciclastics of the Kapp Starostin Formation to the softer, darker areno-argillaceous Vardebukta and equivalent formations. Figure 18.1 shows the distribution of Triassic strata in Svalbard.The minor angular unconformity represents a hiatus mainly in the Permian rather than the Triassic record. The dominantly argillaceous facies constitute the Early Triassic to Late Middle Triassic Sassendalen Group. The rocks can be well dated from ammonoids, typically within calcareous concretions in the shales.The succeding Kapp Toscana Group is distinguished by a dominatly sandy deltaic facies in which age determinations are difficult. It spans both Late Triassic and Early Jurassic spoehs (roughly mid-Ladinian to mid-Bathonian). The Triassic-Jurassic boundary is not easy to estimate. Nevertheless towards the end of Triassic time (e.g. Rhaetian) the overall scene changed. Thus of the three formations of the Kapp Toscana Group the lower two (Tschermakfjellet and De Geerdalen) belong to the Triassic story. The overlying Wilhelmøya Formation may possibly range from Latest Triassic through Liassic time, and due to its complexity it is also discussed in the Jurassic-Crataceous chapter (19).The facies of the two groups reflect two distinct environmental configurations. The Sassendalen Group was deposited on a distal marine muddy shelf with a

Northwestern Spitsbergen, 132 Central western Spitsbergen, 155 Southwestern and southern Spitsbergen, 179 Southern Svalbard: Bjornoya and submarine geology, 209 Camp in snow on the southwestern flank of the icefield Lomonsonfjonna. In the distance the glacier Wilsonbreen flows down between Backlundtoppen on the right and Gotitsynfjellet on the left. The cliffs are mainly of late Neoproterozoic carbonates and tillites. Lomonsovfonna is a large snowfield in central Ny Friesland providing access by sledge down the many valley glaciers which it feeds. Photo M. J. Hambrey CSE 1981. (SP. 985a). View from the icefield Lomonsovfonna, looking north to the high mountains of Ny Friesland from which the glaciers flow westward down to Wijdef]orden. The cliffs expose Proterozoic metamorphic Caledonian basement. Many mountains carry a snow cap resting on an uplifted and exhumed dissected pre-Carboniferous peneplane. The lone sledger (his companion being the photographer) demonstrates transport on a light-weight, sortie from a main camp. Photo M. Typical view in the middle reaches of the glacier, Tryggvebreen, showing present-day transport by (Bombadier) snow scooters. The cliffs are of 'lower Hecla Hock' (Stubendorffbreen Supergroup) Proterozoic Caledonian basement. Snow scooters now provide basic transport, especially in the winter and spring months. In summer they are limited to high snow fields and the upper reaches of the glaciers they feed. Photo M. J. Hambrey, CSE 1982 (SP. 1351).Cliffs of Akademikerbree dolostone/limestone, at Draken in Olav V Land (SE of Ny Friesland). The eight-wheel, tracked, amphibious vehicle is hauling a train of sledges over hard snow and ice; but it travels not so well in deep snow. It was mainly used for crossing marine mud flats from a supply boat, travelling up braided streams or across rotten bay ice. Routine man-hauling also favoured a train of sledges especially across uneven ground to spread the impact of obstacles. Four men would routinely haul two lightly laden 12 foot Nansen sledges and a pulka, divisible into two independent two-man parties.

The area south of Spitsbergen (about 76°31'N) to latitude 74°N, and between longitudes 10°E and 35°E, by which Svalbard was first defined, contains the small island of Bjørnøya (Bear Island, Bären Insel) and the rest is sea (Fig. 11.1).The 500 m isobath conveniently separates the edge of the Barents shelf from the Norwegian Sea Basin which runs south from Spitsbergen between 14° and 16°30'E. To the east, the large shallow area, Spitsbergenbanken, less than 100 m deep, supports Bjørnøya at its southwestern end, extends northeast to Hopen and joins Edge°ya. It is separated from Spitsbergen to the north by the Storfjordyrenna and to the east by Hopendjupet. These submarine valleys appear to drain westwards into the ocean deep with deltaic fronts convex westward.This chapter focuses first on Bjørnøya which though small is a key outcrop in the Barents Sea and distinct in many respects from Spitsbergen being about 250 km distant. The chapter then surveys a little of what is known of the surrounding sub-sea area.Bjørnøya (20 km N-S and 15 km E-W), as the southern outpost of Svalbard, has long been a key to Svalbard geology since it is generally free all year from tight sea ice. But though its location is convenient, its cliffs generally bar access. Indeed there are very few places where landing by other than inflatable dinghy are feasible. After the island had been claimed by a Norwegian syndicate in 1915 mining of Tournaisian coal began in 1916 and exported over 116000