Bulletin of the Geological Society of Denmark, Vol. 39/3-4 Pp. 123-141
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Belemnites from the Lower Jurassic of East Greenland and their biostratigraphical and biogeographical significance PETER DOYLE Doyle, P.: Belemnites from the Lower Jurassic of East Greenland and their biostratigraphical and biogeographical significance. Bull. geol. Soc. Denmark, Vol. 39, pp. 123--141. Copenhagen, December 20th, 1991. https://doi.org/10.37570/bgsd-1991-39-04 Belemnites collected in the 1920s from the Lower Jurassic Neill Klinter Formation of East Greenland are described for the first time. Two belemnite faunas are recognised. The Rrevekl0ft Member yielded Nannobelus, Pseudohastites, Passaloteuthis?, Gastrobelus? and a hastitid, giving an age of the Lower Pliensbachian Uptonia jamesoni to Prodacty/ioceras davoei zones for the molluscan-rich lower fauna! division. The Ostreaelv Member yielded Parapassaloteuthis, Acrocoelites (Toarcibelus), A. (Odontobe /us), Simpsonibelus and "Parabrachybeus" representative of a Toarcian Hildoceras bifrons to Haugia variabilis Zone age as previously determined. However, the presence of Parapassaloteuthis gives a oldest age of at least Dactylioceras commune Subzone, with a loose specimen of a possible juvenile Acrocoe/ites trisulcu!osussugge sting that the Ostreaelv Member may range into the Harpoceras falciferum Zone. The Pliensbachian species are identical to those from western Europe and are the most northerly repre sentatives of their taxa. The Toarcian species have closest affinity to those of northwest Europe rather than the distinct and endemic Siberian Toarcian belemnite fauna which arose at this time. Peter Doyle, School of Earth Sciences, Thames Polytechnic, Wa/burgh House, Big/and Street, London El 2NG England. March 20th, 1991. During the 1926-27 Danish expedition to East sandstone with a marine fauna and underlain by Greenland, Alfred Rosenkrantz studied in detail coal-bearing strata. Subsequent macrofloral work for the first time the Lower Jurassic deposits of determined a "Rhaeto-Liassic" age for the lower Jameson Land. Extensive collections of the rich strata (Kap Stewart Formation), with the over fossil invertebrate fauna were made by Rosenk lying marine strata (Neill Klinter Formation) rantz, and were listed in his subsequent strati yielding Early Pliensbachian and Toarcian fossils graphical publications (Rosenkrantz, 1934, (see Rosenkrantz, 1934, p. 8). An early system 1942). However, of these specimens, only two atic study of the Lower Jurassic beds of south crustacean species ( Glyphaea rosenkrantzi van eastern Jameson Land and Liverpool Land is giv Straelen, 1929, Glyphaea sp.) and one bivalve en in the papers of Rosenkrantz (1929, 1934, (Velata hartzi Rosenkrantz, 1956) have been for 1942). Since this seminal work, detailed aspects mally described (van Straelen, 1929; Rosen of the lithostratigraphy, sedimentology, ichnol krantz, 1956). The purpose of this paper there ogy and palaeogeographical significance of the fore is to describe for the first time Lower Juras Kap Stewart and Neill Klinter formations have sic belemnites from Jameson Land and Liverpool been discussed by Surlyk et al. (1973, 1981), Land, and to discuss their wider stratigraphical Sykes (1974a, b), Dam (1989, 1990) and Surlyk and biogeographical significance. (1990). Surlyk et al. (1973, 1981) and Surlyk (1977, 1978, 1990) traced the development of the sedi ments within the East Greenland Jurassic basin. Stratigraphy Taking a section fromJameson Land in the south to Store Koldewey 0 in the north, a series of William Scoresby (1823) was first to record a blocks active in the Jurassic can be recognised, In stratigraphical succession in Neill Klinter (Neill's the Jameson Land-Scoresby Land area, the basin Cliffs) at Kap Stewart, which was dominated by was downfaulted during Late Triassic to Early 124 Doyle: Belemnites from Greenland SCORESBY LAND JAMESON LAND O Rosenkrantz localities aNeill Klinter Formation SCORESBY SUND Text-fig. 1. Map of Jameson Land and Liverpool Land, showing the outcrop of the Neill Klinter Formation (from Dam, 1989, fig. l), and the approximate positions of the collecting localities of Rosenkrantz (1934). Key to localities: 1, Kap Stewart; 2, Trancrediakloft; 3, Goniomyakloft; 4, Vardekloft; 5, Astartekloft; 6, Harris Fjeld; 7, Constable Pynt; 8, Umingmakbjerg (Umimmak Fjeld); 9, "mountain near Lejrelv" (unnamed); 10, Hjornefjeldet; 11, Igtajigmit (Igterajivit); 12, Kumait. Bulletin of the Geological Society of Denmark Jurassic times allowing the accumulation of, first, gen, Germany; OUM, Oxford University non-marine alluvial sediments (Kap Stewart For- Museum, Oxford, England; WM, Whitby Mu- mation, Rhaetian - Hettangian), followed by seum, Whitby, England. For explanations of the shallow marine deposits (Neill Klinter Forma- terminology used below, see Doyle & Kelly tion, Pliensbachian - Toarcian) deposited in a (1988) and Doyle (1990). The classification used Pliensbachian marine transgression. Lower Ju- below follows that given in the appendix to Doyle rassic rocks are absent elsewhere in East Green- (in press). Approximate size (length) ranges are land. Subsequent deepening of this basin in later given by the terms smal1 (c50 mm), medium Jurassic times led to the accumulation of the shelf (50-80 mm) and large (>80 mm). Measurements sediments of the Vardekl~ftFormation (Hein- (in mm): L, total preserved length; 1, length from berg & Birkelund, 1984) which caps the Lower protoconch to apex; Dv, dorsoventral diameter Jurassic sediments in Neill Klinter. at the protoconch; Dl, lateral diameter at the Three members are presently recognised protoconch; Dvmax, maximum dorsoventral di- within the Neill Klinter Formation: RæveklØft ameter; Dlmax, maximum lateral diameter; x, Member (Lower Pliensbachian, Uptonia jame- distance from apex to position of maximum in- soni and Prodactylioceras davoei zones have been flation of the rostrum. For brevity, in most of the recognised) (= Pecten limestone series of Ro- synonymies only the original valid description senkrantz, 1934, p. 21); Gule Horn Member (denoted thus*), the most recent references (with (largely lacking body fossils, possible Upper ful1 synonymy), and the citations of Rosenkrantz Pliensbachian); Ostreaelv Member (Toarcian, (1936) traceable to individual specimens still pre- Hildoceras bifrons and "Lytoceras jurense" sent in the Geologisk Museum are given. The zones) (= Oyster bank series of Rosenkrantz, symbol v indicates the type andlor figured speci- 1934, p. 21). The RzeveklØft Member comprises mens have been examined. Subj., subjective syn- coarse sandstones indicative of a high energy en- onym; obj., objective synonym. The approxi- vironment (see fig. 2 of Dam, 1990). The Os- mate location of Rosenkrantz's collecting stations treaelv Member comprises shelf and subaqueous are given in text-fig. 1. shelf sandstones (fig. 2 of Dam, 1990) with uplift in the source area providing the coarse clastics. Class Cephalopoda Cuvier, 1794 The intervening Gule Horn Member was prob- Subclass Coleoidea Bather, 1888 ably deposited in a lower energy, shallow, pos- Order Belemnitida Zittel, 1895 sibly intertidal, environment (Surlyk et al., 1973; Suborder Belemnitina Zittel, 1895 Dam, 1990). Family Belemnitidae d'orbigny, 1845 The belemnites described below were reco- vered from the RzveklØft and Ostreaelv mem- Subfamily Belemnitinae d'orbigny, 1845 bers, collected from southeastern Jameson Land and southern Liverpool Land. The specimens Nannobelus Pavlow, 1913 were accurately located by Rosenkrantz in his (= Prototeuthis Lemoine, 1915, obj.; non Nan- paper (Rosenkrantz, 1936), although using in nobelus Saks & Nal'nyaeva, 1970) some cases informal geographical names. These localities are given in fig. 1. Type species: Belemnites acutus Miller, 1826, by original designation. Systematic descriptions Diagnosis: Smal1 conical to cylindriconical Be- lemnitinae; outline and profile symmetrical, con- All specimens are housed in the Geologisk Mu- ical to cylindriconical; apex acute; transverse sec- seum, Copenhagen (GM), unless otherwise tions subquadrate to pynform; apical grooves ab- stated. The Geologisk Museum prefix MGUH sent, though apex may bear striae; lateral lines denotes specimens in the type and figured collec- two faint subparallel depressions on each flank; tion. Other repositories: BMNH, Natural His- apical line ortholineate; phragmocone penetrates tory Museum, London, England; GPIT, Geol- one-quarter to one-third rostrum. ogisches und Palaontologisches Institut, Tubin- Doyle: Belemnites from Greenland Plae 1. PI& 1-5, PsuOIIRPIItu apiapicIcai~(BlainGUe): l, 2. vmml outline and profile, MGUH 20673, d; 3, ptafile, MGUH m74. xl; 4.5, venid nuiitlineyd piirle, MGUA 211675, XI.Ep 6,7. Hm-sp., eritraioutlirrewid paofite, MGUHXWZ, x1.5. F@ &9,Nannubetu d alvaplaus (Werner), ventrd outfine and prof&. KURml, x5.5, [email protected]. P@w~oI&~?sp., wnt~aloutline and profite. M(3UH2M76. XI. Bulletin of the Geological Society of Denmark Range: Lower Sinemurian to Lower Pliensba- Passaloteuthis or Pseudohastites, this specimen chian of Europe (Britain, Germany, France, may safely be assigned to the genus Nannobelus Italy, Denmark (Bornholm: GM 1879.742, N. because it lacks any vestige of apical grooves. acutus?), Sweden, Bulgaria, Czechoslovakia), The specimen closely resembles N. alveolatus Turkey, ?North Africa and East Greenland. Sib- (Werner), which is equally elongated, but it is erian "Nannobelus" of Toarcian age (Saks & Nal- only tentatively assigned to this species because it 'nyaeva, 1970) are endemic homeomorphs now