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The Triassic of Svalbard consists of two lithostratigraphic groups. The dominant lithologies inthe Sassendalen Group are of Early to Middle Triassic age and consist of shales and siltstoneswith minor amounts of sandstone and carbonates (Mørk et al., 1999). Mørk et al. (1982)suggested that the sandstone units exposed on the western coast of Svalbard are related tocoastal progradation from Greenland in the west. The Sassendalen Group has coastal todeltaic sediments exposed on the western Spitsbergen, which grade into organic-rich shelfmudstones eastwards in Svalbard and southwards into the Barents Sea Shelf (Mørk et al.,1999).The Kapp Toscana Group is deposited during the Middle Triassic to Middle Jurassic in adeltaic environment. There is still some local deltas prograding from the west, affecting thewestern coast of Svalbard (Worsley, 2008), while Riis et al. (2008) suggests that the Uralsprovide the major part of the sediment input, leading to a delta-plain environment over muchof the northern Barents Shelf (For more detailed information about the Triassic succession atSvalbard see subsection 1.4).The Adventdalen Group represents the sediments deposited on Svalbard during the latestMiddle Jurassic to Early Cretaceous. The Group contains claystones, shales and sandstonesdeposited in shelf settings (Mørk et al., 1999). During the Barremian, HelvetiafjelletFormation was deposited on Svalbard. This significant sandstone unit was deposited as aresult of the Cretaceous regional uplift, as well as deltaic progradation and relative sea levelfall. For the period of latest Jurassic to earliest Cretaceous dolerite sills and dikes intrudedolder rocks all across Svalbard (Gjelberg and Steel, 1995). These intrusions were a result ofthe break-up between Greenland and Europe (Burov et al., 1977; Birkenmajer et al., 2010).The Late Cretaceous uplift exposed Svalbard and subjected the northwestern rim of theBarents Shelf to erosion, preferentially in the north because the erosion cuts deeper into theCarolinefjellet Formation strata here than in the south and northwest (Steel and Worsley,1984). This uplift of the northwestern edge of the Barents Shelf was probably part of adoming related to development of the Artic Basin to the north (Steel and Worsley, 1984).The Tertiary basins of Svalbard developed in a period of considerable tectonic activity, incontrast to the Mesozoic depositional platform (Steel and Worsley, 1984). The CentralTertiary basin is situated in the southern and central parts of the island Spitsbergen. This basin6
forms a NNW-SSE trending synclinorium, infilled with clastic sediments (Dallmann et al.,1999b).During the glaciation cycles in the Neogene, large amounts of sediments were redeposited onthe shelf edge. Repeated shelf depression and uplift took place causing erosion, and shapedthe topography that we can see on Svalbard today (Worsley, 2008).1.4 The Triassic succession on SvalbardTriassic rocks crop out extensively on the Svalbard archipelago. On the eastern side of thearchipelago the exposed rocks are fairly horizontal, while on western Svalbard the sedimentsare folded and thrusted as a result of the Tertiary deformation (Mørk et al., 1982; Bergh et al.,1997; Braathen et al., 1999). As mentioned in Subsection 1.3 the Triassic of Svalbard consistsof two lithostratigraphic groups; the Sassendalen Group and the Kapp Toscana Group. OnHopen the sediments are of Late Triassic age, and belong to the Kapp Toscana Group.The Kapp Toscana Group is deposited during late Middle Triassic to Middle Jurassic time andconsists of sandstones and mudstones. During the deposition of the Late Triassic StorfjordenSubgroup (Figure 1.3) deltaic and floodplain environments were established over much of theSvalbard Platform (Worsley, 2008), and in the upper part of Storfjorden Subgroup the DeGeerdalen Formation was deposited on Svalbard.The Carnian to early Norian De Geerdalen Formation is underlain by the grey shales of theTschermakfjellet Formation and overlain by the Wilhelmøya Subgroup (Figure 1.3). Theformation is suggested to be diachronous and to have more proximal facies to the southeast(Lock et al., 1978; Mørk et al., 1982; Riis et al., 2008). The De Geerdalen Formation thickensto the east and southeastwards, from 200-300 meters on central and eastern Spitsbergen(Mørk et al., 1999; Mørk and Worsley, 2006) to about 700 meters on Hopen (Riis et al. 2008).The lower boundary is defined at the base of the first pronounced sandstone bed above theTschermakfjellet Formation (Mørk et al., 1999). The De Geerdalen Formation is the dominantformation on Hopen and consists of shales, silts and sandstones. This island is situated on thesouth-eastern border of the Svalbard archipelago, hence the outcrops on Hopen are mostlikely illustrating the most proximal part of the De Geerdalen Formation. Larger sandstonebodies, some even in seismic scale can be seen several places at Hopen (e.g. Subsection 4.1.1:Channel body 1). On some of the higher mountains, like Lyngefjellet (Figure 1.4), the De7
Page 1: Visualize and interpret the geometr
Page 5 and 6: SammendragEn digital 3D-modell av H
Page 7: 4.2.3 Channel body 8 (SW of Lyngefj
Page 10 and 11: Secondly, I wish to thank my co-sup
Page 12 and 13: 1.3 Regional geological settingThe
Page 16 and 17: Geerdalen Formation is overlain by
Page 18 and 19: 1.5 Previous work at HopenThe Swedi
Page 21 and 22: 2. MethodsThe work of this thesis i
Page 23 and 24: 2.2 PhotoModeler-modelThe program P
Page 25 and 26: 2.3 Sources of errorThere are no kn
Page 27 and 28: 3. Lateral distribution of possible
Page 29 and 30: Figure 3.2: This photo and drawing
Page 31 and 32: 3.2 Lateral distribution of Slottet
Page 33 and 34: Hopen member and the top of the mou
Page 35 and 36: 4. Channel bodiesIn this chapter ob
Page 37 and 38: 4.1.1 Channel body 1 (Northern chan
Page 39 and 40: Figure 4.2: Photos and illustration
Page 41 and 42: 4.1.2 Channel body 2 (Binnedalen)Ch
Page 43 and 44: Figure 4.4: This figure illustrates
Page 45 and 46: (1) DiscussionFacies occurring in t
Page 51 and 52: 4.1.4 Channel Body 4 (Johan Hjortfj
Page 53 and 54: Figure 4.10: Photos and illustratio
Page 55 and 56: The log shows that the channel body
Page 57 and 58: 4.2.1 Channel body 5 (SW of Nørste
Page 59 and 60: (1) DiscussionOne of the interestin
Page 61 and 62: Another explanation of the apparent
Page 63 and 64: Figure 4.14: This figure illustrate
Page 65 and 66:
4.2.4 Channel body 9 (Blåfjellet,
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Figure 4.16: Illustrates Channel bo
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The outcrop orientations and/or a n
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Unfortunately the stratigraphic int
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Figure 4.22: An illustration of the
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2006). Flaser bedding is characteri
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elow the stratigraphical level of C
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indications on the logs from the st
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Figure 4.27: This figure illustrate
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Figure 4.28: This Figure illustrate
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is perhaps the best indication of a
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4.31: This figure illustrates the w
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Figure 4.32:Interpretation offault
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4.3.1 Channel body 15 (NW of Braast
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4.3.2 Channel body 16 (Blåfjellet
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4.3.3 Channel body 17 (Djupskaret)C
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Figure 4.36: This figureillustrates
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5. Discussion5.1 Map relevant featu
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Geerdalen Formation of no more than
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ase of Hopen member. Going further
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6. Conclusions18 channel bodies are
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ReferencesAinsworth, R. B., Vakarel
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Knarud, R. 1980. En sedimentologisk
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AppendixAppendix 1: The measured se
Page 116 and 117:
108
Page 118 and 119:
Appendix 2: Legend of the measured
Page 120 and 121:
Appendix 4: Illustrations of the Ph
Page 122:
Figure 6: Illustration of the Photo
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