GEUS Bulletin no 5.pmd

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76 75 A new Middle–Upper Jurassic succession, up to 360 m thick, was found recently on northern Hold with Hope, North-East Greenland (Fig. 1; Stemmerik et al. 1997; Kelly et al. 1998; Larsen et al. 1998). It spans the Early Callovian – Early Kimmeridgian time interval as indicated by dinoflagellate cysts and ammonites, and consists of coarse-grained sandstones overlain by heteroliths and mudstones. The sandstone-dominated lower part of the succession assigned here to the Pelion Formation was originally studied by Koch (1932) and Maync (1949) and was tentatively given an Early Cre- 52 Greenland 28 Milne Land 24ºW PDMF Jameson Land DCF Traill Ø 20ºW 16ºW Kuhn Ø Store Koldewey Wollaston Forland Clavering Ø Fig. 2 Hold with Hope Geographical Society Ø DCF PDMF 76ºN 74ºN 72ºN Jurassic Fault Dombjerg–Clavering Fault Post-Devonian Main Fault 100 km GEUS Bulletin no 5.pmd 52 29-10-2004, 11:14 Fig. 1. Map of East Greenland showing the distribution of Jurassic sediments and major faults. Rectangle marks the investigated area on northern Hold with Hope, shown in more detail in Figure 2. Modified from Koch & Haller (1971) and Surlyk et al. (1973). taceous age, although W. Maync noted the resemblance to the Middle Jurassic succession on Wollaston Forland. The apparent absence of Jurassic sediments in the Hold with Hope area was explained differently by Maync (1947), Donovan (1957), Surlyk (1977) and Stemmerik et al. (1993). Maync (1947) and Surlyk (1977) suggested that during the Jurassic the area formed a landmass between the Wollaston Forland Basin to the north and the Jameson Land Basin to the south, implying that the lack of sediments was primarily due to non-deposition. Donovan (1957) in contrary found it
74º00'N ■■ ■■ ■■ 73º55'N ■■ ■■ ■■ ■■ Spath Plateau 2 km ■■■■ 1 ■■ ■■ ■■ Blåelv Stensiö Plateau ■■ ■■ ■■ ■■ ■■ ■■ 21º15'W 3A 3B 3C 3D most likely that the absence was secondary owing to pre-Aptian erosion of the Jurassic rocks. Based on comparison with nearby Clavering Ø, Stemmerik et al. (1993) suggested that Middle–Upper Jurassic sediments were present in the subsurface east of the continuation of the Dombjerg–Clavering Fault on Hold with Hope (Fig. 1, DCF). The present investigations confirm that Hold with Hope formed a landmass between the Wollaston Forland and Jameson Land Basins during much of the Middle Jurassic time interval. The discovery on Hold with Hope of a marine succession of Early Callovian – Kimmeridgian age, however, shows that the land mass was flooded in late Middle Jurassic time and continued to be sea-covered for most of the remaining Jurassic period. Gulelv ■■■■ 3E ■■ ■■■■ ■■ ■■ ■■ 5 4 ■■ ■■ ■■ ■■ ■■ ■■ ■■ Sortelv ■■ ■■ ■■ ■■ 2 ■■ 6 ■■ 7 ■■ ■■ ■■ ■■ ■■ ■■ 8 ■■ ■■ Steensby Bjerg Ice Undifferentiated superficial deposits Dolerite sill Plateau basalt Paleocene Lower Cretaceous Middle and Upper Jurassic Lower Triassic Permian Crystalline basement ■■ ■■ ■■■■ ■■ 21º00'W Gael Hamke Bugt ■■ ■■ 9 ■■ Normal fault Inferred fault Locality Cross-section (log panel) The Jurassic succession on Hold with Hope is subdivided into shallow marine sandstones of the Pelion and Payer Dal Formations (Vardekløft Group) and lower shoreface – offshore transition heteroliths and offshore mudstones of the Bernbjerg Formation (Hall Bredning Group). The Pelion Formation includes the new Spath Plateau Member, which contains abundant sandy heteroliths in contrast to the dominant clean sandstone lithology of the Pelion Formation. The sedimentary facies of the units are described and the depositional environments interpreted. The Jurassic succession is placed within a regional framework including the Wollaston Forland and Jameson Land Basins to the north and south, respectively. ■■ ■■ 3 ■■■■ ■■ ■■ Diener Bjerg Fig. 2. Geological map of part of northern Hold with Hope including position of localities mentioned in text. The composite section from Gulelv (Fig. 5) was compiled from five part-sections (A–E). The solid lines show schematically the orientation of the NE–SW and NW–SE log panels in Figures 7 and 8, respectively. GEUS Bulletin no 5.pmd 53 29-10-2004, 11:14 ■■ ■■ ■■ ■■ ■■ ■■ ■■ ■■ ■■ ■■ ■■ Fosdalen ■■ ■■ ■■ ■■ ■■ Hold with Hope 53
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 and 36: SW NE Lycett Bjerg Parnas Member Be
Page 37 and 38: Cadoceras cf. nordenskjoeldi Callom
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: A new Middle-Upper Jurassic success
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
Page 91 and 92: 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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