GEUS Bulletin no 5.pmd

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part, and are followed by mudstones of the Bernbjerg Formation that yield Upper Oxfordian – Lower Kimmeridgian ammonites (Surlyk 1978). The outcrops at Kulhus and Agnetesøelven expose the main part of the Jurassic succession in Hochstetter Forland. These localities were visited during fieldwork in 1987 in order to collect material for palynological analysis with the aim of refining the stratigraphy. The present paper describes for the first time the dinoflagellate cyst floras from these northern outcrops close to the transition to the Boreal dinoflagellate cyst province, for example in Peary Land (Håkansson et al. 1981) and on Svalbard (Århus 1988). 90 Agnetesø 2 3 Kulhus 1 20ºW Agnetesøelven Nanok Søndre Muslingebjerg 20 km N 76º30'N Greenland HOCHSTETTER FORLAND 1: Milne Land 2: Jameson Land 3: Wollaston Forland 4: Hochstetter Forland 5: Store Koldewey 6: Germania Land 7: Peary Land Undifferentiated, mostly glacial deposits Cretaceous Jurassic Caledonian crystalline basement Locality Fault 7 6 4 3 1 500 km Material GEUS Bulletin no 5.pmd 90 29-10-2004, 11:14 1 5 2 Fig. 1. Simplified sketch map of Hochstetter Forland illustrating the Jurassic outcrops and the sampled localities. The map is modified from Surlyk (1978, fig. 1). At Kulhus (Fig. 1; Locality 1), on the south coast of Hochstetter Forland west of Søndre Muslingebjerg, sand and coal seams were sampled during a ground stop on helicopter reconnaissance in 1987. Only one sample (GGU 351570) contains dinoflagellate cysts. Two closely situated localities at Agnetesøelven were spotted from the air and visited during a short ground stop. The westernmost sandstone outcrop (Locality 2) was measured and two fine-grained samples with at least some potential for palynology were collected from two horizons (Fig. 2). Eastwards and down-river, the sandstone-dominated succession was seen to be faulted against a succession of laminated mudstones (Locality 3), and this was closely sampled for palynology (Fig. 3). Only a few, well-preserved dinoflagellate cysts were recovered from the sand succession at Locality 2. By
Fig. 2. Sedimentological log of the upper Payer Dal Formation at Agnetesøelven (Locality 2) showing the positions of analysed samples. contrast dinoflagellate cysts are abundant but poorly preserved in the mudstones at Locality 3. Ammonites are abundant in the lower, pyritic, part of the mudstone succession and in loose concretionary beds at the base of the cliff. These ammonites provide independent stratigraphical control of the dinoflagellate cyst assemblages. All of the samples from the three localities on Hochstetter Forland were prepared by traditional palynological methods and analysed for their content of dinoflagellate cysts. m 35 30 25 20 15 10 5 0 Mud Sand 351538 351537 Geology The Jurassic succession on Hochstetter Forland is divided into the Muslingebjerg, Payer Dal and Bernbjerg Formations of the Vardekløft Group. The marine sandstones of the Payer Dal Formation were previously included in the Pelion Member of the Vardekløft Formation (sensu Surlyk 1978); the Pelion Member is now raised to formation status (Surlyk 2003, fig. 5). Kulhus (Locality 1) GEUS Bulletin no 5.pmd 91 29-10-2004, 11:14 Structures Lithology Fossils, etc. 351537 Planar lamination/bedding Planar cross-lamination Lenticular lamination Trough cross-bedding Scour and fill Shell bed Fine-grained sand Mud Pyrite Ammonite Belemnite Bivalve Oyster Pecten spp. Planolites ispp. Wood Bioturbation GGU sample Hard bed The low coastal cliff at Kulhus, south-west Hochstetter Forland (Fig. 1, Locality 1), comprises 3–4 main coal 91
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GEOLOGICAL SURVEY OF DENMARK AND GR
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GEUS Bulletin no 5.pmd 3 29-10-2004
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Contents Preface . . . . . . . . .
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(Alsen & Surlyk 2004, this volume).
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Jurassic syn-rift sedimentation on
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NW SE m 1000 500 0 NW SE m 1000 500
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GEUS Bulletin no 5.pmd 13 29-10-200
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grained than the lower parasequence
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the Pelion Formation. The mudstone-
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The fluviatile Bristol Elv Formatio
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Name. After the river Bristol Elv i
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edded, and display both sheet-like
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N S Fig. 5. Coarse-grained sandston
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Fig. 7. Lacustrine deposits from th
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deposition of peat and coal. Journa
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Maximum Middle Jurassic transgressi
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834 N Lycett Bjerg Barrikade Gletsc
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SW NE Lycett Bjerg Parnas Member Be
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Cadoceras cf. nordenskjoeldi Callom
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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: Jurassic dinoflagellate cysts from
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 115 and 116: 185 Greenland from Archaean to Quat
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GEUS Bulletin no 5.pmd

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