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

More documents

Recommendations

Info

tion, but are abundant in the cuttings from the middle and upper part of the GRO#3 well (Nøhr-Hansen 1997c). Depositional environment. Deposition of the Anariartorfik Member took place in a fault-controlled slope environment (Dam & Sønderholm 1994). Most of the channellised amalgamated turbidite sandstone beds were deposited from high-density turbidity currents in confined low-sinuosity channels, although a few examples of giant-scale, cross-bedded sandstones are interpreted as the products of lateral accretion in meandering slope channels. The thinly interbedded sandstones and mudstones are interpreted as having been deposited from traction currents and from fall-out processes associated with various sedimentation stages within waning low-density currents. The lateral continuity and the lack of systematic vertical thickness variations in the thinly interbedded sandstones and mudstones suggest that these deposits were not confined by channel-levee systems, but most likely represent interchannel slope deposits. Where present, the chaotic beds always underlie undisturbed channel sandstones. This suggests that the channels were initially excavated by retrogressive slumping of unstable sediments on the slope followed by channel excavation by scouring (Dam & Sønderholm 1994). Boundaries. The lower and upper boundaries of the Anariartorfik Member are not exposed. The upper boundary was drilled in the GRO#3 well but not cored (Fig. 67). An erosional unconformity between the Anariartorfik Member and the overlying Kangilia Formation was suggested by Kristensen & Dam (1997). Geological age. Palynomorphs in the GRO#3 well indicate a ?Coniacian/Santonian – early Maastrichtian age for the uppermost c. 525 m of the Anariartorfik Member. In the lowermost 1510 m of the well, the organic material is degraded due to thermal maturation and this part of the formation cannot be dated (Nøhr-Hansen 1997c). Umiivik Member new member History. Outcrops of marine Upper Cretaceous strata referred to the Umiivik Member on Svartenhuk Halvø and northern Nuussuaq have only been briefly described by earlier workers since their main focus was on the collection of fossils (Rosenkrantz et al. 1942; Birkelund 1956, 1965; Rosenkrantz 1970). Later studies in connection with mapping by the Geological Survey and drilling of stratigraphic wells in the Umiivik area of Svartenhuk Halvø have been reported by Christiansen (1993), Dam et al. (1998b), Christiansen et al. (2000) and J.G. Larsen & Pulvertaft (2000). On northern Nuussuaq, extensive stratigraphic studies have been carried out at Annertuneq and Kangilia (Christiansen et al. 1992; Christiansen 1993; Christiansen et al. 1994) and at Serfat in connection with drilling of mineral exploration wells (Dam & Nøhr-Hansen 1995). Name. The member is named after the stretch of shore located south-east of Firefjeld in the inner part of the Umiiviup Kangerlua bay, eastern Svartenhuk Halvø (Fig. 73). Distribution. On Svartenhuk Halvø, the Umiivik Member is locally exposed in the north-western part of the peninsula (Fig. 2), and more extensively in the low-lying coastal outcrops around the bay of Umiiviup Kangerlua, and c. 5 km north-west of the south-eastern corner of the peninsula (Fig. 73). On Nuussuaq, exposures are found along the north coast between Niaqornat and Ikorfat and in the Tunorsuaq valley (Figs 2, 74). On Svartenhuk Halvø, the member has been cored in five shallow wells (GGU 400708–712; Christiansen 1993; Christiansen et al. 1994a) and in the deep Umiivik- 1 well (Fig. 73; Christiansen et al. 1994; Nøhr-Hansen 1996; Christiansen et al. 1997; Dam 1997; Nøhr-Hansen 1997a; Dam et al. 1998b). On the north coast of Nuussuaq the member has been penetrated in six shallow boreholes: GGU 400705–707 and FP4-11-02, FP94-11-04 and FP94-11-05 (Chri - stiansen et al. 1994; Dam & Nøhr-Hansen 1995), and in the deep GANT#1 well (Fig. 74; Christiansen et al. 1996c; Dam 1996a; Dahl et al. 1997; Nøhr-Hansen 1997b; Kierkegaard 1998). Type section. The most complete section of the member is available in the Umiivik-1 core drilled on the southern shore of Umiiviup Kangerlua on Svartenhuk Halvø (GGU 439301; Figs 73, 75). Neither the base nor the top of the member is, however, seen in this well. The cores are stored at GEUS in Copenhagen. The Umiivik-1 well is located at 71°36.70´N, 54°02.52´W. Reference sections. The best-exposed outcrops of the Umiivik Member are found below the Kangilia Formation (Annertuneq Conglomerate Member) at Annertuneq and Kangilia on the north coast of Nuussuaq (Figs 72, 92
Umiivik-1 m Overburden ★ ★ No palynomorphs recorded due to thermal influence from igneous intrusions 900 1000 1100 ★ ★ ★ ★ ★ ★ ★ ★ ?Upper Turonian 500 600 700 ★ ★ Upper Coniacian Upper Turonian – ?Upper Coniacian 100 200 300 ★ ★ ★ ★ ★ Upper Turonian ★ 400 ★ 1200 clay si vf fmcvc sand 800 clay si vf fmcvc clay si vf fmcvc sand sand ★ Fig. 75. Sedimentological log showing type section of the Umiivik Member (Itilli Formation) in the Umiivik-1 well. For location, see Fig. 73; for legend, see Plate 1. Modified from Dam et al. (1998b). 87). At Annertuneq, the GGU cores 400705–707 were drilled to supplement the outcrop studies (Fig. 74; Christiansen et al. 1994). In the GANT#1 well, the interval from 255.8 m to 900.6 m (Fig. 76) is assigned to the Umiivik Member (Dam 1996a). The cores are stored at GEUS in Copenhagen. Thickness. The total thickness of the Umiivik Member is unknown, but in the Umiivik-1 well on Svartenhuk Halvø it is at least 960 m thick (excluding a total of 22 dolerite intrusions with a cumulative thickness of 240.2 m). In the slopes behind the Umiivik-1 drill site, approximately 185 m of poorly exposed mudstone is present below the base of the hyaloclastic volcanic rocks of the Vaigat Formation – this part of the succession is partly penetrated by the cores 400710–711 (Fig. 73; Christiansen et al. 1994). In the GANT#1 well, on northern Nuussuaq, 620 m have been cored (excluding intrusions). Lithology. The Umiivik Member is dominated by black mudstones intercalated with laminae and thin beds of sandstone; carbonate concretions are common (Figs 75, 93
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 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 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: VK 53°30’ 53°15’ Niaqornat Tu
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
show all

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

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?