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

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Fig. 91. Mudstones interbedded with sandstone and channellised conglomerates (arrows point to base of conglomerate-filled channels). The Kangilia Formation at Ataa; for location, see Fig. 40. Height of the section is c. 50 m. small number of in situ ammonites (Hoploscaphites aff. H. angmartussutensis) and echinoderms have been found in a sandstone bed in the lower part of the formation and in scattered concretions (Nøhr-Hansen & Dam 1997; Kennedy et al. 1999). Palynomorphs are common and are referred to five zones from the Wodehouseia spinata Zone to the Palaeocystodinium bulliforme Zone (Nøhr- Hansen 1997b; Nøhr-Hansen et al. 2002). The Oyster–Ammonite Conglomerate Bed in Agatdalen is made up of highly fossiliferous concretions containing a mainly Maastrichtian fauna of ammonites although concretions with Campanian and Danian species are also present. The matrix of the conglomerate contains Danian oysters and other bivalves, gastropods, crustaceans and rare specimens of other fossils (Birkelund 1965; Rosenkrantz 1970). On the south coast of Nuussuaq, fossils are very scarce in the Kangilia Formation and only indeterminate thinshelled bivalves and gastropods have been found in the mudstones at Ivisaannguit. The trace fossil Planolites isp. and escape burrows occur locally in the sandstone beds. Depositional environment. The presence of dinocysts, echinoderms and ammonites indicates a marine depositional environment and the mudstones and sandstones dominating the formation are interpreted to have been deposited from waning, low-density turbidity currents whereas the conglomeratic units were deposited from 108
channellised, high-density currents. Some of the mudstones may also have been deposited from suspension. The conglomerates and sandstones at the base of the Kangilia Formation exhibit a characteristic suite of facies that indicate deposition from catastrophic flows related to high-density, turbidity currents and debris flows. On the north coast of Nuussuaq deposition took place in a slope environment, probably in a major submarine canyon setting (Figs 76, 87). At Ataata Kuua, the lower part of the formation was deposited in a submarine canyon (Figs 15, 92) whereas the mudstones in the upper part were deposited by dilute turbidity currents in an unconfined slope setting. The basal erosional unconformity represents a transverse section through the submarine canyon (Figs 15, 92; Dam & Nøhr-Hansen 2001). The thin lenticular fining-upward successions are interpreted as minor turbidite channel deposits. Dinocysts and macrofossils suggest general marine conditions during deposition. Along the south coast of Nuussuaq, at Ataata Kuua and Ivisaannguit, no marine palynomorphs have been recorded (McIntyre 1993), suggesting a dominant terrestrial input. Boundaries. The lower boundary is an erosional unconformity that separates the Kangilia Formation from the underlying Atane Formation on southern Nuussuaq (Fig. 15) and from the Itilli Formation on western, central and northern Nuussuaq (Figs 14, 87, 88). Along the north coast of Nuussuaq, in the GANT#1 and GRO#3 wells and at Ataata Kuua, the lower boundary is picked at the base of a thick conglomerate unit that cuts down into the underlying deposits of the Itilli and Atane Formations. At all these localities, the lower boundary marks the base of a major submarine canyon system (Fig. 92; Dam & Nøhr-Hansen 2001). Where the basal conglomerate is absent, the unconformity between the Itilli and Atane Formations is difficult to locate using lithological criteria (mudstone overlying mudstone) and has to be picked on the basis of biostratigraphic data. On Itsaku (Svartenhuk Halvø), there is an angular unconformity between the Kangilia Formation and the underlying sediments of the Upernivik Næs Formation. At this locality, a thick conglomerate unit occurs at the base of the formation. Elsewhere on Svartenhuk Halvø, the formation locally onlaps the basement or is in faulted contact with the Umiivik Member of the Itilli Formation (Fig. 73; J.G. Larsen & Pulvertaft 2000). The Kangilia Formation is overlain by the Eqalulik Formation on northern and western Nuussuaq (Figs 87, 118), the Agatdal Formation on central Nuussuaq and possibly on Itsaku (Fig. 113), and by the Quikavsak Formation on southern Nuussuaq (Fig. 99A). Geological age. The dinocyst flora suggest a late Maa - strichtian to Danian age for the Kangilia Formation on the north coast of Nuussuaq and a Danian age in the central part of Nuussuaq (Fig. 16; J.M. Hansen 1970; Nøhr- Hansen 1996, Nøhr-Hansen & Dam 1997; Nøhr- Hansen et al. 2002). The type section of the Kangilia Formation provides a well-exposed section across the Cretaceous–Tertiary (K/T) boundary in a clastic, deep-water setting (Fig. 87; Nøhr-Hansen & Dam 1997). Ammonites in the lowermost part of the formation indicate a late Maastrichtian age (Kennedy et al. 1999) and coccoliths indicate that most of the section above the K/T boundary has a nanofossil NP3–4 Zone age and consequently that NP2 and A B Submarine canyon incision Submarine canyon filling Deltaic sandstone Turbidite sandstone Turbidite mud-rich heterolith ? ? Deltaic mudstone Clasts Fig. 92. Conceptual model for the formation of the submarine canyon fill of the Kangilia Formation at Ataata Kuua. From Dam & Nøhr-Hansen (2001 fig. 4). The canyon formed in response to listric faulting, detachment and collapse of the hanging wall (A). The steeply dipping part of the detachment surface of the footwall acted as the canyon wall and seems not to have been eroded to an appreciable extent. During a subsequent transgression, the canyon was filled with turbidite deposits (B). Colours reflect interpreted depositional environments (see Plate 1). 109
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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
Page 9 and 10:
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
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
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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
Page 31 and 32:
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
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Gilbert delta in the Ikorfat area (
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150 300 450 100 250 400 m 550 50 20
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Fig. 36. Outcrop of the Upernivik N
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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: m 150 140 130 120 110 100 90 Kangil
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
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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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