GEUS Bulletin no 5.pmd

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Fig. 6. Sedimentological log of core GGU 303124, measured by J. Therkelsen and P. Alsen. For location, see Figs 2, 5. Family Cardioceratidae von Siemiradzky 1891 Genus Cadoceras Fischer 1882 Cadoceras sp. Plate 1, figs 2A–C, 3 Material. Several fragments preserved as imprints in black shale (MGUH 25763–766 from GGU 429771; GGU 429772). The assemblage includes well-preserved small specimens of microconchs, some of which are almost complete (Plate 1, figs 2A–C). Horizon. The assemblage was collected at a small exposure in the streambed of the Bjørnedal River in 36 Olympen Formation Fossilbjerget Formation m 50 40 30 20 10 0 cl si f m c gr sand GEUS Bulletin no 5.pmd 36 29-10-2004, 11:14 Ch Te Ch Te Rh ? Te Ch Ch Te Te Te Pa Th ? Ph Te Te Sandstone Siltstone Cross-lamination Wavy lamination Parallel lamination - Degrees of bioturbation Te Terebellina isp. Ph Phycosiphon isp. Th Thalassinoides isp. Pa Palaeophycus isp. Ch Chondrites isp. Rh Rhizocorallium isp. Bjørnedal, Traill Ø. The succession was not measured, but belongs to unit B (Fig. 4). Description. The fragments seem to be those of macroconchs. They are densely ribbed with relatively coarse, strong primaries and secondaries. Size cannot be estimated. The microconchs are small and evolute with dense, very fine ribbing. Ribbing becomes somewhat coarser near the final peristome. The maximum diameter is on average about 16 mm. Age. The specimens are early Cadoceras (J.H. Callomon, personal communication 1997) probably from the C. apertum or C. nordenskjoeldi Chronozones (Fig. 3; faunas 27–30 of Callomon 1993). The assemblage thus indicates an Early Callovian age.
Cadoceras cf. nordenskjoeldi Callomon & Birkelund 1985 Plate 1, fig. 4A–C 1904 Olcostephanus Neumayr (?Simbirskites Pavlow & Lamplugh) nov. sp. – Madsen, p. 195, plate 10, fig. 2. cf. 1985 Cadoceras nordenskjoeldi n. sp. Callomon & Birkelund, p. 84, pl. 1, fig. 4; pl. 4, figs 1–6. Material. Several fragments (MGUH 25767–769 from GGU 429768). The fragments are small and crushed macroconchs and are poorly preserved in hard, reddish sandstone. Complete specimens and microconchs have not been identified. Horizon. The assemblage was found loose in unit C at Locality 3 between the mudstones exposed at Localities 1 and 2 (Figs 2, 4, 5). Description. The inner whorls are finely and densely ribbed and seem to be evolute. The outer whorls are evolute, with very coarse and blunt primary and secondary ribbing. The whole assemblage seems to consist of fairly slim variants. Comparisons. The specimens are referred to as C. cf. nordenskjoeldi, which has the above-mentioned characteristic style of ribbing. This is supported by their stratigraphical position above K. tenuifasciculatus. Age and distribution. This is the first find of the species outside the Fossilbjerget and Olympen areas in central Jameson Land. C. cf. nordenskjoeldi indicates an Early Callovian age (C. nordenskjoeldi Chron; Fig. 3). Cadoceras sp. indet. Plate 1, fig. 5 Material. Two specimens and fragments (MGUH 25770 from GGU 429767; GGU 429769–770). One specimen is a poorly preserved macroconch (Plate 1, fig. 5); the other is a poorly preserved microconch. Both are imprints in mudstones. Horizon. The ammonites were collected at Locality 2 from level 29–30.6 m in section JT-14 (Fig. 2) in mudstones of unit D (Figs 2, 4, 5). Description. The macroconch is medium-sized and evolute, and comprises most of a whorl of the bodychamber. Ribbing is dense and relatively strong up to the aperture. Primaries divide into secondaries on the middle of the flank. The specimen shows no adult modification and could be a juvenile. Maximum diameter measures 61.5 mm. The other specimen, probably a microconch, is small and relatively evolute. Ribbing is dense and sharp with primaries and secondaries. Maximum diameter is 30 mm. Age. The assemblage is too poorly preserved for determination to specific level. The specimens are possibly early Cadoceras of Early Callovian age (J.H. Callomon, personal communication 1997; Fig. 3). Acknowledgements We acknowledge generous support by the Danish Research Councils (Project: ‘Resources of the sedimentary basins of North and East Greenland’) and thank Jette Halskov for drafting, Jens Therkelsen, who provided the measured sections, John H. Callomon and Lars Stemmerik for reading the manuscript critically, and Walter K. Christiansen and G. Bloos for useful reviews. References Including references cited in Appendix GEUS Bulletin no 5.pmd 37 29-10-2004, 11:14 Alsen, P. 1998: Middle Jurassic ammonite biostratigraphy in the Traill Ø region, central East Greenland. Abstracts – 23rd Nordiske Geologiske Vintermøde Århus, Denmark, 1998, 17 only. Birkelund, T., Callomon, J.H. & Fürsich, F.T. 1984: The stratigraphy of the Upper Jurassic and Lower Cretaceous sediments of Milne Land, central East Greenland. Bulletin Grønlands Geologiske Undersøgelse 147, 56 pp. Buckman, S.S. 1922: Type Ammonites 4, 67 pp., pls 267–422. London: Wheldon & Wesley. Callomon, J.H. 1993: The ammonite succession in the Middle Jurassic of East Greenland. Bulletin of the Geological Society of Denmark 40, 83–113. Callomon, J.H. 2003: The Middle Jurassic of western and northern Europe: its subdivisions, geochronology and correlations. In: Ineson, J.R. & Surlyk, F. (eds): The Jurassic of Denmark and Greenland. Geological Survey of Denmark and Greenland Bulletin 1, 61–73. Callomon, J.H. 2004: Description of a new species of ammonite, Kepplerites tenuifasciculatus n. sp., from the Middle Jurassic, Lower Callovian of East Greenland. Appendix in: 37
Page 1 and 2: GEOLOGICAL SURVEY OF DENMARK AND GR
Page 3 and 4: GEUS Bulletin no 5.pmd 3 29-10-2004
Page 5 and 6: Contents Preface . . . . . . . . .
Page 7 and 8: (Alsen & Surlyk 2004, this volume).
Page 9 and 10: Jurassic syn-rift sedimentation on
Page 11 and 12: NW SE m 1000 500 0 NW SE m 1000 500
Page 15 and 16: grained than the lower parasequence
Page 17 and 18: the Pelion Formation. The mudstone-
Page 19 and 20: The fluviatile Bristol Elv Formatio
Page 21 and 22: Name. After the river Bristol Elv i
Page 23 and 24: edded, and display both sheet-like
Page 25 and 26: N S Fig. 5. Coarse-grained sandston
Page 27 and 28: Fig. 7. Lacustrine deposits from th
Page 29 and 30: deposition of peat and coal. Journa
Page 31 and 32: Maximum Middle Jurassic transgressi
Page 33 and 34: 834 N Lycett Bjerg Barrikade Gletsc
Page 35: SW NE Lycett Bjerg Parnas Member Be
Page 41 and 42: 4 C B 1 2 GEUS Bulletin no 5.pmd 41
Page 43 and 44: Fig. 1. Sketch-map of the Jameson L
Page 45 and 46: Table 1. Measurement of dimensions
Page 49 and 50: 1 2 GEUS Bulletin no 5.pmd 49 29-10
Page 51 and 52: A new Middle-Upper Jurassic success
Page 53 and 54: 74º00'N ■■ ■■ ■■ 73º5
Page 55 and 56: System Ma 159.4 154.1 164.4 169.2 1
Page 57 and 58: Sedimentary structures Biota Struct
Page 59 and 60: wards units is biogenic carbonate d
Page 61 and 62: Fig. 7. Log panel giving a broadly
Page 63 and 64: SPM LU to medium-grained and consis
Page 65 and 66: and mudstone drapes reflects varyin
Page 67 and 68: with the presence of a minor angula
Page 69 and 70: the north-east and south-west, resp
Page 71 and 72: elly mass-flow deposits. In: Koster
Page 73 and 74: Jurassic dinoflagellate cyst strati
Page 75 and 76: 74°00'N ■■ ■■ ■■ 73°5
Page 77 and 78: Bernbjerg Formation Payer Dal Forma
Page 79 and 80: Depositional environment. The prese
Page 85 and 86: Metres 30 20 10 Hold with Hope, Loc
Page 87 and 88:
Correlations The Pelion Formation o
Page 89 and 90:
Jurassic dinoflagellate cysts from
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Fig. 2. Sedimentological log of the
Page 93 and 94:
LITHOSTRATIGRAPHY BIOSTRATIGRAPHY F
Page 95 and 96:
ALPHABETICAL SPECIES LIST 41 Adnato
Page 97 and 98:
References Alsgaard, P.C., Felt, V.
Page 99 and 100:
Jurassic dinoflagellate cyst strati
Page 101 and 102:
parties from the Geological Survey
Page 103 and 104:
may indicate a hiatus in the sedime
Page 105 and 106:
Metre 50 25 0 Store Koldewey Ravn P
Page 107 and 108:
Fig. 6. Schematic stratigraphical c
Page 109 and 110:
Chronozone) to the earliest Kimmeri
Page 111 and 112:
The Upper Jurassic succession is co
Page 113 and 114:
GEUS Bulletin no 5.pmd 113 29-10-20
Page 115 and 116:
185 Greenland from Archaean to Quat
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GEUS Bulletin no 5.pmd

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