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

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m 40 A B C m 36 Slibestensfjeldet Fm m 38 30 30 30 Kome Formation 20 Kome Formation 20 Kome Formation 20 ★ 10 10 10 ★ 0 mud sand gravel 0 mud sand gravel 0 mud sand gravel Section base 20 m above sea level (a.s.l.) 2 m a.s.l. 242 m a.s.l. Fig.25. Reference sections of the Kome Formations illustrating abrupt facies change and numerous horizons with rootlets. A and B are from the lower part of the formation and C and D are from the uppermost part of the formation. Sections C and D also show the overall decrease in grain-size towards the west. The boundary between the Kome Formation and the overlying Slibestensfjeldet Formation is shown in section C. From Midtgaard (1996b). For legend, see Plate 1; for location, see Fig. 22. 42
Kome Formation m 40 30 20 D tial relief was levelled out as sediments accumulated and buried the highs. The alluvial fans were succeeded by fan deltas representing both subaerial and subaqueous deposition; the latter increases towards Ikorfat (Fig. 25D). The sparse dinocyst assemblage indicates that the water was intermittently brackish. The coarse sandstones of facies association A at Kuuk are interpreted as fluvial deposits. Their low textural and mineralogical maturity together with palaeocurrent indicators point to derivation directly from a weathered basement to the south-east, without reworking en route, and to rapid sedimentation. The dark mudstones are interpreted as overbank deposits of a floodplain environment or deposition in shallow lakes. The mudstones of facies association B are interpreted as having been deposited from suspension in bodies of standing water, presumably interdistributary bays or lakes (Fig. 23, 24). Sedimentary structures in the sandstones of facies association C suggest deposition from a sandy braided river flowing from the south, and the higher textural and mineralogical maturity of the sandstones indicates more protracted fluvial transport (Pulvertaft 1979). The palaeosol that caps the Kome Formation represents a widespread regressive event (Figs 25C, 30; Midtgaard 1996b). 10 0 mud 290 m a.s.l. sand gravel Boundaries. The Kome Formation overlies an undulating Precambrian gneiss topography, filling valleys or depressions (Henderson et al. 1976; Schiener 1977; Pulvertaft 1979; Midtgaard 1996b). The lower boundary of the formation is exposed at Kuuk, Ikorfat and Talerua (Figs 2, 21, 22). In the coastal cliffs of northern Nuussuaq, the relief on the gneiss surface can be seen to exceed 225 m (Fig. 22). At Vesterfjeld, the basement is weathered to a depth of 30 m with a gradual downward transition into unaltered gneiss. In western Disko (Stordal), the Precambrian basement is exposed, locally with a 5−10 m thick weathered cap (A.K. Pedersen & Ulff-Møller 1980). In other exposures, the gneiss is relatively unweathered (Schiener 1977; Midtgaard 1996b). The lower boundary of the Kome Formation thus displays a variety of basement−sediment transitions. The upper boundary of the Kome Formation is a sharp lithological boundary that varies very little laterally (Figs 25C, 30). It is placed on top of a palaeosol horizon and was interpreted as a sequence boundary by Midtgaard (1996b). Previous workers, e.g. Nordenskiöld (1871), Gry (1942) and Midtgaard (1996b), have considered the Kome Formation to be overlain by the Atane Formation on Nuussuaq. We propose that the new Slibestensfjeldet Formation separates the Kome and Atane 43
Page 1 and 2: GEOLOGICAL SURVEY OF DENMARK AND GR
Page 4 and 5: Contents Abstract . . . . . . . . .
Page 7 and 8: Preface The onshore Cretaceous-Pale
Page 9 and 10: Introduction The Nuussuaq Basin bel
Page 11 and 12: chemistry of the Nuussuaq Basin hav
Page 13 and 14: Fig. 5. Plant fossils from the Atan
Page 15 and 16: Peak 2010 m Peak 1900 m Peak 1760 m
Page 17 and 18: A lithostratigraphy for the marine
Page 19 and 20: to provide further funding for stud
Page 21 and 22: 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: m m 15 14 14 13 12 11 10 9 8 7 6 5
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 and 74: Type section. The type section of t
Page 75 and 76: Fig. 56. Delta front succession of
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
Page 125 and 126:
Vaigat Formation sill Quikavsak For
Page 127 and 128:
Fig. 112. The sharp boundary betwee
Page 129 and 130:
Agatdal Formation Eqalulik Formatio
Page 131 and 132:
Fig. 116. Basal conglomerate unit o
Page 133 and 134:
heterolithic deposits of the Kangil
Page 135 and 136:
GANE#1 Vaigat Fm Anaanaa Mb m Hyalo
Page 137 and 138:
Fig. 121. Well reference section of
Page 139 and 140:
Pedersen 1978). The beds are usuall
Page 141 and 142:
In detail, however, the boundary be
Page 143 and 144:
Fig. 126. Composite type section of
Page 145 and 146:
m m 240 340 m Pingu Member 230 230
Page 147 and 148:
Naujât Member Atane Formation, Kin
Page 149 and 150:
The TOC [Total Organic Carbon] cont
Page 151 and 152:
Fig. 133. Correlation of the member
Page 153 and 154:
Fig. 135. Type locality of the Ping
Page 155 and 156:
Fig. 137. Lower, sharp boundary of
Page 157 and 158:
m 130 125 110 t t invasive lava low
Page 159 and 160:
Fig. 141. Upper part of the Assoq M
Page 161 and 162:
Brown, R. 1875: Geological notes on
Page 163 and 164:
a rosetted spreite trace fossil: Da
Page 165 and 166:
ing bark from the Nûgssuaq peninsu
Page 167 and 168:
1998: The syn-volcanic Naajaat lake
Page 169 and 170:
Appendix: Place names and localitie
Page 171:
Place name Place name P Paatuut sou
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Geological Survey of Denmark and Greenland Bulletin 19 ... - Geus

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