Geological Survey of Denmark and Greenland Bulletin 19 ... - Geus

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m m 140 130 Itilli Formation Kussinerujuk Member 20 10 0 120 Tr vf f m c vc clay silt sand 110 Atane Formation Kingittoq Member 100 90 80 70 Tr Fig. 55. Reference section of the Kingittoq Member at Asuk, north coast of Disko (for location, see Fig. 2). The section is domi - nated by stacked delta front deposits and intervals assigned to the delta plain facies association are thin. Note that only one thin coal seam is present (44 m). See also Figs 56, 57 and 80. At this locality, the member is clearly more influenced by marine deposition than at Kingittoq (Fig. 53). Tr, transgressive sandstones. For legend, see Plate 1. 60 Tr Tr 50 40 30 20 10 0 vf f m c vc clay silt sand Tr Tr Tr debris. Marine fossils are found locally and bioturbation is generally slight. Thin beds of well-sorted, structureless sandstone are seen at Kingittoq, whereas similar beds at Asuk show erosional bases and contain numerous trace fossils, of which Ophiomorpha nodosa is prominent (Fig. 55). Fossils. Plant macrofossils, spores and pollen are known from the Kingittoq Member (Heer 1883a, b; Seward 1926; Ehman et al. 1976; Croxton 1978a, b; Lanstorp 1999). Heer (1883b) described plant fossils collected from four outcrops of the Kingittoq Member (Qullissat, Asuk, Qallunnguaq, and Atanikerluk) and referred these to the Atane flora and the Patoot flora. Marine dinocysts are known from the Kingittoq Member (D.J. McIntyre, personal communication 1997) and finds of rare individuals of three marine invertebrates, Nucula cancellata, Nucula sp., and Lucina occidentalis, were reported from Kingittoq (Ravn 1918). The trace fossils Ophiomorpha nodosa, Taenidium serpentinum, Teichichnus rectus, Thalassinoides isp. occur locally in the Kingittoq Member. 74
Fig. 56. Delta front succession of the Kingittoq Member at Asuk (27–35 m in Fig. 55). Note the upward increase in frequency and thickness of sandstone beds. The well-sorted sandstones with hummocky and swaley cross-stratification (S) are indicative of a high-energy depositional environment. The mudstone (M) at the top of the section is interpreted as an interdistributary bay deposit. For location, see Fig. 2. M S delta front Depositional environment. The Kingittoq Member is interpreted to represent fluvial to deltaic deposits and is referred to four facies associations: the channel and delta plain associations (dominant), the delta front or mouth bar association (subordinate) and the transgressive sand sheet association (rare) (Midtgaard 1991; G.K. Pedersen & Pulvertaft 1992; Dam et al. 2000; Jensen 2000; Nielsen 2003; G.K. Pedersen et al. 2006). The cross-bedded, medium- to coarse-grained sandstones are interpreted as fluvial channel deposits. The sedimentary structures frequently indicate downstream accretion on bars and rare development of point bars, indicating that the fluvial channels were mostly braided. The complex sheets of coarse-grained sandstones are interpreted as having been deposited as the multi-storey fill of fluvial valleys (Jensen 2000; Jensen & Pedersen in press). The carbonaceous mudstones, sandstones and coal beds are interpreted to represent the vertical aggradation of subaerial to freshwater lacustrine or swamp deposits. The high C/S ratios indicate that deposition occurred in freshwater environments on the upper delta plain (G.K. Pedersen & Pulvertaft 1992; Nielsen 2003). The coal beds are interpreted as the in situ accumulations of plant remains in freshwater environments (Bojesen-Koefoed et al. 2001; G.K. Pedersen et al. 2006). This facies association is subordinate at Asuk. The coarsening-upward heteroliths are interpreted as delta front or mouth bar deposits formed during progradation of shelf deltas (G.K. Pedersen & Pulvertaft 1992; Bojesen-Koefoed et al. 2001; Nielsen 2003; G.K. Pedersen et al. 2006). This facies association is dominant at Asuk. The thin beds of sand with marine trace fossils are interpreted as transgressive sand sheets (Midtgaard 1991). The erosive base constitutes a ravinement surface. In the Kingittoq Member, the transgressive sand sheets are best developed at Asuk. The Kingittoq Member is dominated by stacked upper delta plain deposits in the Atanikerluk area and at Qullissat, and by lower delta plain and stacked delta front deposits at Asuk. Boundaries. The lower boundary of the Kingittoq Member is exposed on northern Nuussuaq where the Kingittoq Member overlies the Ravn Kløft Member (Fig. 50). Here the boundary is a drowning surface which separates the fluvial sandstones from the overlying delta plain deposits. In the rest of the Nuussuaq Basin, the lower boundary is not exposed. The upper boundary, corresponding generally to the upper boundary of the Atane Formation in the outcrop area of the member, is everywhere an erosional unconformity overlain by the Itilli, Quikavsak, Atanikerluk and Vaigat Formations (Fig. 16). On the north coast of 75
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GEOLOGICAL SURVEY OF DENMARK AND GR
Page 4 and 5:
Contents Abstract . . . . . . . . .
Page 7 and 8:
Preface The onshore Cretaceous-Pale
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Introduction The Nuussuaq Basin bel
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chemistry of the Nuussuaq Basin hav
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Fig. 5. Plant fossils from the Atan
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Peak 2010 m Peak 1900 m Peak 1760 m
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A lithostratigraphy for the marine
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to provide further funding for stud
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DGR Geological setting As a result
Page 23 and 24: TSS 8 Agatdal Fm Eqalulik Fm Kangil
Page 25 and 26: A Svartenhuk Halvø 50 km B Hinterl
Page 27 and 28: Nuussuaq Group new group History. T
Page 29 and 30: ley (Figs 2, 40, 65). The section a
Page 31 and 32: Central Nuussuaq Agatdalen South co
Page 33 and 34: 3 10 4 6 5 Qorlortorssuaq Slibesten
Page 35 and 36: volcanic sediments are referred to
Page 37 and 38: Fig. 20. View from Uummannaq toward
Page 39 and 40: In the Kuuk area, the sediments ove
Page 41 and 42: m m 15 14 14 13 12 11 10 9 8 7 6 5
Page 43 and 44: Kome Formation m 40 30 20 D tial re
Page 45 and 46: Fig. 28. Reference locality of the
Page 47 and 48: Vaigat Fm Vesterfjeld Slibestensfje
Page 49 and 50: Gilbert delta in the Ikorfat area (
Page 51 and 52: 150 300 450 100 250 400 m 550 50 20
Page 53 and 54: Fig. 36. Outcrop of the Upernivik N
Page 55 and 56: Correlation. The Upernivik Næs flo
Page 57 and 58: 12’ 09’ 15’ 06’ 03’ Saqqa
Page 59 and 60: m 0 GGU 247801 200 400 247815 ★
Page 61 and 62: wave-rippled sand streaked mudstone
Page 63 and 64: the formation in the marine mudston
Page 65 and 66: d d Fig. 47. Type locality of the S
Page 67 and 68: Fig. 49. Cross-bedded medium- to co
Page 69 and 70: and Qaarsut (Fig. 22). Its wider di
Page 71 and 72: Fig. 52. Two closely spaced section
Page 73: Type section. The type section of t
Page 77 and 78: Fig. 59. The Kingittoq Member at Ki
Page 79 and 80: sh L sh ch delta front Vaigat Forma
Page 81 and 82: Fig. 63. Type locality of the Itivn
Page 83 and 84: 782 Quaternary cover 54° 888 Malig
Page 85 and 86: Kuugannguaq-Qunnilik Fault and is o
Page 87 and 88: and include clasts of intraformatio
Page 89 and 90: deposited in a base-of-slope and ba
Page 91 and 92: VK 53°30’ 53°15’ Niaqornat Tu
Page 93 and 94: Umiivik-1 m Overburden ★ ★ No p
Page 95 and 96: 76). Heavily bioturbated interbedde
Page 97 and 98: Fig. 78. Type locality of the Kussi
Page 99 and 100: A B Itilli Formation Kussinerujuk M
Page 101 and 102: 160 140 120 100 Vaigat Formation Eq
Page 103 and 104: Fig. 85. Mudstones and conglomerati
Page 105 and 106: Fig. 87. Type section of the Kangil
Page 107 and 108: m 150 140 130 120 110 100 90 Kangil
Page 109 and 110: channellised, high-density currents
Page 111 and 112: Thickness. The Annertuneq Conglomer
Page 113 and 114: Fig. 96. A: Type locality of the Oy
Page 115 and 116: On Svartenhuk Halvø, on the east s
Page 117 and 118: Fig. 100. Reference locality of the
Page 119 and 120: Tupaasat Member Atane Formation Fig
Page 121 and 122: ever, have a fluvio-lacustrine orig
Page 123 and 124: etween Tupaasat and Nuuk Qiterleq a
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Vaigat Formation sill Quikavsak For
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Fig. 112. The sharp boundary betwee
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Agatdal Formation Eqalulik Formatio
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Fig. 116. Basal conglomerate unit o
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heterolithic deposits of the Kangil
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GANE#1 Vaigat Fm Anaanaa Mb m Hyalo
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Fig. 121. Well reference section of
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Pedersen 1978). The beds are usuall
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In detail, however, the boundary be
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Fig. 126. Composite type section of
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m m 240 340 m Pingu Member 230 230
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Naujât Member Atane Formation, Kin
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The TOC [Total Organic Carbon] cont
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Fig. 133. Correlation of the member
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Fig. 135. Type locality of the Ping
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Fig. 137. Lower, sharp boundary of
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m 130 125 110 t t invasive lava low
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Fig. 141. Upper part of the Assoq M
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Brown, R. 1875: Geological notes on
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a rosetted spreite trace fossil: Da
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ing bark from the Nûgssuaq peninsu
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1998: The syn-volcanic Naajaat lake
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Appendix: Place names and localitie
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Place name Place name P Paatuut sou
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Geological Survey of Denmark and Greenland Bulletin 19 ... - Geus

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