GEUS Bulletin no 5.pmd

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Appendix 42 Plate 1 Description of a new species of ammonite, Kepplerites tenuifasciculatus n. sp., from the Middle Jurassic, Lower Callovian of East Greenland John H. Callomon A new species of ammonite, Kepplerites tenuifasciculatus n. sp., is described. Its type locality is at Fossilbjerget in central Jameson Land, East Greenland and its type horizon lies in the Apertum Zone, the lowest zone in the Lower Callovian Stage of the Middle Jurassic. It has a narrow stratigraphical range and hence makes a good guide-fossil for stratigraphical time correlation. Keywords: ammonite, East Greenland, Fossilbjerget, Jameson Land, Kepplerites tenuifasciculatus n. sp., Middle Jurassic Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK. E-mail: johncallomon@lineone.net The revision of the biostratigraphy and biochronology of the ammonite faunas of the Middle Jurassic of East Greenland has revealed a number of hitherto unknown species that characterize very narrow chronostratigraphic intervals and hence make excellent guide-fossils for time correlations (Callomon 1993). One of these is now described. It represents a transient – chronospecies of some authors – in the evolution of one of the two evolutionary lineages, the Kosmoceratidae, whose members inhabited East Greenland during the Late Bathonian and Callovian, the other being the much longer-ranging Cardioceratidae. Superfamily Stephanocerataceae Neumayr 1875 Family Kosmoceratidae Haug 1887 Genus Kepplerites Neumayr & Uhlig 1892 Type species. Amm. keppleri Oppel 1862. Kepplerites tenuifasciculatus n. sp. Plate 1, figs 1–2 GEUS Bulletin no 5.pmd 42 29-10-2004, 11:14 1993 Kepplerites sp. nov. J [tenuifasciculatus MS] Callomon, p. 103. Holotype. Plate 1, fig. 1, MGUH 25310 from GGU 185614a (T. Birkelund and C. Heinberg collection 1974) Jameson Land, Fossilbjerget, section 43, bed 14, horizon J27 (Figs 1, 2). Other material. Paratypes I, II, MGUH 25311–312 from GGU 185614b, c; paratype III, MGUH 25313 from JHC 4475 (Plate 1, fig. 2; T. Birkelund and J.H. Callomon collection 1971), same locality and bed; JHC 4469–4471, section 42, bed 18 (see Fig. 2); GGU 144191–192 from south slopes of mount Mikael Bjerg, section 31 (Birkelund coll. 1971; Fig. 1). Numerous other specimens seen in situ were too poorly preserved to be worth collecting. Stratigraphical horizon. The southern slopes of Fossilbjerget are marked by three ridges, running southwards, on which sections have been recorded, numbered 41–43 from east to west (Callomon 1993, fig. 1).
Fig. 1. Sketch-map of the Jameson Land area with place names mentioned in the text. The sections span the shaly Fossilbjerget Formation underlain by the sandy Pelion Formation and capped by the sandstones and shales of the Olympen Formation (Surlyk et al. 1973; Larsen & Surlyk 2003). The three sections differ only in detail. Section 43 is shown in weathering-profile in Figure 2. It was previously shown in outline by Surlyk et al. (1973, fig. 23). Lithologically, the sediments consist predominantly of shaly siltstones or very fine-grained sandstones, barely consolidated except in concretionary layers that punctuate the succession as markers or in scattered calcitic or phosphatic concretions. Some of the beds are highly glauconitic, indicating condensed, sediment-starved intervals and comparison with adjacent areas, e.g. at the mountains Olympen and Mikael Bjerg (Fig. 1), shows that the succession incorporates numerous hiatuses of variable durations. The age-diagnostic ammonites can be recovered only from the hard beds. Their biostratigraphy in terms of faunal horizons, however, 25 24ºW Scoresby Sund Scoresby Land Olympen Jameson Land 23ºW Mikael Bjerg GEUS Bulletin no 5.pmd 43 29-10-2004, 11:14 Greenland Schuchert Dal Pelion Fleming Fjord Fossilbjerget Ugleelv Sortehat Katedralen 22ºW 71ºN 50 km is with only few exceptions as close to complete as present knowledge allows (Callomon 1993, fig. 4). The only horizon in the interval under discussion not so far recognized in the Fossilbjerget–Olympen area is J23, that of Kepplerites vardekloeftensis. It may have been lost in a hiatus, marked by a sharp lithological break, under the glauconitic ironstones of beds 9–13 (Fig. 2, Section 43). The type-horizon of Kepplerites tenuifasciculatus, J27, is bed 14, an indurated, shaly, non-glauconitic, light brown fine-grained sandstone, 0.2 m thick, lying with sharp contact on the hard, ferruginous and highly glauconitic sandstone marker of bed 13 below (Fig. 2, Section 43). The contact probably marks another hiatus that would account for the considerable break, both in composition and morphologies, between the faunas of beds 13 and 14. The fauna of bed 13 consists predominantly of Cadoceras (apertum), with only minor Kepplerites (cf. traillensis). That of bed 14 is dominated by monospecific Neill Klinter 0 Kong Oscar Fjord Hurry Inlet Carlsberg Fjord 43
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: 4 C B 1 2 GEUS Bulletin no 5.pmd 41
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
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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