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

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E W Vaigat Formation Asuk Member Atane Formation Kingittoq Member Itilli Formation Kussinerujuk Member Fig. 79. Outcrops of the Itilli Formation at the western end of the coastal cliff section at Asuk. Outcrops of the Atane Formation are seen farthest to the east (left); for detail, see Fig. 57. The pale sandstones (centre-left) are impregnated with hydrocarbons (see Bojesen-Koefoed et al. 2007).The dark grey mudstones in the centre of the photograph are referred to the Kussinerujuk Member as are the sandstones to the west. The dark-weathering rocks cropping out above these sandstones are referred to the volcanic Asuk Member (Vaigat Formation). These volcanic rocks are part of a major landslide, and the complicated structural relationships between the pale sandstones and the mudstones of the Itilli Formation suggest that the coastal exposures may be affected by landslides. The height of the cliff is c. 30 m. For location, see Fig. 2. surface capping the Atane Formation east of the Kuuganguaq–Qunnilik Fault. The genetic relationships between the two outcrop areas of the member are, however, poorly understood. The conglomerates at the type locality at Kussinerujuk were deposited from channellised sediment gravity flows at unknown water depths possibly generated by slope failure in a deeply incised channel. Farther east, at Asuk and Qorlortorsuaq, the mudstonedominated succession is tentatively interpreted to be deposited in a marine environment during transgression. Deposition occurred below storm wave base on a gently sloping sea floor from low-energy unconfined turbidity currents or distal storm-generated flows. Boundaries. The lower boundary, as exposed at Kussinerujuk, Asuk and Qorlortorsuaq (Fig. 2), is an erosional unconformity where mudstones or mud-clast conglomerates sharply overlie deltaic sandstones of the Atane Formation (Kingittoq Member; Figs 16, 55, 77). The upper boundary is not exposed, but is probably an erosional unconformity overlain by Paleocene hyaloclastite breccias of the Vaigat Formation. Geological age. Spores, pollen and dinocysts indicate a Cenomanian to Late Turonian age for the member at Kussinerujuk (McIntyre 1994a, b; this study). Dinocysts indicate a Cenomanian age at Asuk (Fig. 16; Bojesen- Koefoed et al. 2007). Itilli Fm Kussinerujuk Mb Atane Fm Kingittoq Mb Fig. 80. Erosional unconformity between the Atane Formation and the Itilli Forma - tion (see Fig. 55) in the coastal cliff east of Asuk. The coastal cliff is c. 30 high. For location, see Fig. 2. 98
A B Itilli Formation Kussinerujuk Member Fig. 81. A: Silt-streaked mudstone with small-scale load structures in the Kussinerujuk Member (Itilli Formation) at Asuk. Lens cap for scale. B: Land-slipped deposits of erosionally based sandstones interbedded with mudstones at Asuk are assigned to the Kussinerujuk Member of the Itilli Formation. Encircled persons for scale; for location, see Fig. 2. Correlation. The Kussinerujuk Member is coeval with parts of the Umiivik and Anariartorfik Members of the Itilli Formation. Aaffarsuaq Member new member History. The un-named Upper Cretaceous marine sandstones and shales exposed on central Nuussuaq that were informally referred to the Aaffarsuaq member by Dam et al. (2000), are mainly known for the remarkable discoveries in 1952 of huge specimens of Upper Santonian – Lower Campanian inoceramid (Sphenoceramus) bivalve shells (Fig. 71; Rosenkrantz 1970). Name. The member is named after the Aaffarsuaq valley on central Nuussuaq (Fig. 82). Distribution. The member is found on central Nuussuaq where it is well exposed along the south-facing slopes of Aaffarsuaq between Qilakitsoq and Tunoqqu. Minor exposures are present in a stream section on the northfacing slope of Aaffarsuaq, south of Nalluarissat, in Kangersooq (Fig. 82) and in Turritelladal at Scaphites - næsen, and in Agatdalen where the Teltbæk fault crosses the Agatdalen river (Figs 82, 113; Dam et al. 2000). Type section. The type section is located in the second ravine east of Qilakitsoq on the northern slopes of Aaffarsuaq (Figs 82, 83). The base of the type section is located at 70°28.70´N, 53°21.97´W. Reference sections. Well-exposed reference sections occur in ravines on the northern side of Aaffarsuaq along Nalluarissat, between Qilakitsoq and Tunoqqu (Fig. 82). Thickness. In the main outcrop area, the thickness of the member decreases eastward from c. 250 m in the type section to 65 m at Tunoqqu. Lithology. The Aaffarsuaq Member is characterised by amalgamated sandstone and rip-up mudstone and sandstone clast conglomerate units alternating with thinly interbedded sandstones and mudstones, dark, sandstreaked mudstones, and chaotic beds of homogeneous mudstone commonly cut by sandstone dykes and synsedimentary faults (Figs 83, 84, 85, 86; Dam et al. 2000). The amalgamated sandstone and conglomerate units of the Aaffarsuaq Member consist of very coarse- to medium-grained sandstone and conglomerate beds grading upwards into thinly interbedded sandstones and mudstones. These coarse-grained units are up to 50 m thick and extend laterally beyond the extent of outcrop (several hundred metres) or occasionally form lenticular bodies. Individual beds have planar erosional bases and internally show normal grading. Beds are from
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GEOLOGICAL SURVEY OF DENMARK AND GR
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Contents Abstract . . . . . . . . .
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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
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TSS 8 Agatdal Fm Eqalulik Fm Kangil
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A Svartenhuk Halvø 50 km B Hinterl
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Nuussuaq Group new group History. T
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ley (Figs 2, 40, 65). The section a
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Central Nuussuaq Agatdalen South co
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3 10 4 6 5 Qorlortorssuaq Slibesten
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volcanic sediments are referred to
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Fig. 20. View from Uummannaq toward
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In the Kuuk area, the sediments ove
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m m 15 14 14 13 12 11 10 9 8 7 6 5
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Kome Formation m 40 30 20 D tial re
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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: Fig. 78. Type locality of the Kussi
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
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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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