Geological Survey of Denmark and Greenland Bulletin 23, 2011, 61–64 61 Scattered occurrences of Palaeogene sediments are found in North-East Greenland, where they overlie unconformably Cretaceous sediments and are capped by Palaeogene basalts. These sediments have received little attention (Watt 1994), except for relatively recent studies (Nøhr-Hansen & Piasecki 2002; Jolley & Whitham 2004; Larsen et al. 2005; Heil- mann-Clausen et al. 2008). As part of an ongoing petroleum geological study that focuses on the Jurassic–Cretaceous suc- cession, the Palaeogene sediments were included to better constrain their age, depositional environment and relation to the basalts. Several localities were investigated on Wollaston Forland, Sabine Ø and Hold with Hope, a few of which are described here (Fig. 1). Eastern Wollaston Forland and Sabine Ø Discontinuous outcrops of mostly loose and un-cemented Palaeogene sediments occur in Haredal, eastern Wollaston Forland. A N–S-striking normal fault with 100–125 m of downthrow to the east separates the main outcrop in the southern slope into two blocks. The best exposed succession is situated in the western footwall block, where the succes- sion dips 20° to the SW (Fig. 2). It overlies marine mudstones of Late Albian age (Wigginsiella grandstandica Subzone (V1) of Nøhr-Hansen 1993) in the footwall block and of Early to Middle Campanian age (indicated by the dinocysts Alterbi- dinium ioannidesii and Cerodinium diebelii) in the hanging wall block; however, the contact to the Cretaceous is not ex- posed. A poorly exposed Palaeogene succession in the north- ern slope is probably from the hanging wall block; the base of the succession and underlying strata are not exposed. Haredal, southern slope. Approximately 200 m of Palaeogene sediments are partly exposed in the footwall block, forming two upward-coarsening units overlain by basalts (Fig. 2). The lower unit consists of more than 70 m of dark grey mud overlain by 54 m of fine- to medium-grained sand beds al- ternating with thinner heteroliths topped by more than 2 m of coarse-grained sand. The succession is of earliest Ypresian age based on the presence of the dinocyst Apectodinium au- gustum (Fig. 3) and the nannofossil Discoaster lenticularis. The palynological assemblage is dominated by reworked ma- terial from Upper Jurassic (e.g. Gonyaulacysta jurassica), mid to Upper Cretaceous (e.g. Hapsocysta benteae, Chatangiella spp. and Wodehouseia spinata) and lower Paleocene (e.g. Al- isocysta margarita). The presence of A. augustum may cor- relate with the A. augustum (P6b) Subzone described from the central North Sea (Mudge & Bujak 1996) and correlated Palaeogene deposits in North-East Greenland Henrik Nøhr-Hansen, Lars Henrik Nielsen, Emma Sheldon, Jussi Hovikoski and Peter Alsen Fig. 1. Geological map of the Wollaston Forland – Hold with Hope study area in North-East Greenland. The location of the studied sections cor- responds to the distribution of Palaeogene sediments. © GEUS, 2011. Geological Survey of Denmark and Greenland Bulletin 23, 61–64. Open Access: www.geus.dk/publications/bull Young Sund G a e l H a m k e B u g t Lille Pendulum Kap Broer Ruys Sabine Ø Wollaston Forland Hold with Hope Palnatoke Bjerg Ice Quaternary Intrusive complexes (48–28 Ma) Basaltic sills and dykes Basaltic plateau lavas (58–54 Ma) Palaeogene Cretaceous Jurassic Triassic Palaeozoic Daneborg To b i a s D a l 20°W 74°N Jackson Ø Harefjeld Haredal Fosdalen Langsiden Dronning Augusta Dal 25 km Home Forland Faults Studied section Greenland 6262 E le v at io n 400 m 380 360 340 320 300 280 260 240 220 200 E . P al ae o ge n e P e ri o d /E p o c h S ta ge Palyno zones Palyno zones C h ro n o - st ra ti gr ap h y C h ro n o - st ra ti gr ap h y P 6 A . a u g u st u m Z o n e P 6 b A . a u g u st u m S u b zo n e S am p le s P a la e o p e ri d in iu m p yr o p h o ru m A p e ct o d in iu m a u gu st u m A re o lig e ra s p p . C e ro d in iu m s tr ia tu m D e fl a n d re a o e b is fe ld e n si s P a la e o cy st o d in iu m b u lli fo rm e T h a la ss ip h o ra d e lic a ta A p e ct o d in iu m p a n ic u la tu m G la p h yr o cy st a r e ti in te xt a A lis o cy st a m a rg a ri ta C e ro d in iu m d ie b e lii P a la e o cy st o d in iu m a u st ra lin u m C e ro d in iu m s p e ci o su m P h th a n o p e ri d in iu m s p p . ? ? ?? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? Dinoflagellate Cysts Haredal southern slope, eastern Wollaston Forland Haredal southern slope Haredal northern slopeD is co a st e r le n ti cu la ri s D is co a st e r ge m m e u s? H e lic o sp h a e ra s e m in u lu m T ri b ra ch ia tu s o rt h o st yl u s NA N P Z o n e s Z o n e E le v at io n 220 A. augustum top A. augustum base A. augustum base A. margarita base T. evittii top m 200 180 160 140 120 100 80 60 E . P al ae o ge n e P e ri o d /E p o c h S ta ge P 6 A . a u gu st u m Z o n e S u b zo n e S am p le s A re o lig e ra s p p . C e ro d in iu m d ie b e lii G la p h yr o cy st a c f. r e ti in te xt a P a la e o p e ri d in iu m p yr o p h o ru m S p o n go d in iu m d e lit ie n se T ri th yr o d in iu m e vi tt ii S e n o n ia sp h a e ra i n o rn a ta A lis o cy st a m a rg a ri ta C o rd o sp h a e ri d iu m i n o d e s D in o c y st s p 4 H N H 2 0 0 2 M u ra to d in iu m f im b ri a tu m P a la e o cy st o d in iu m b u lli fo rm e S e n e ga lin iu m i te rl a a e n se C e ro d in iu m s tr ia tu m A p e ct o d in iu m a u gu st u m A p e ct o d in iu m p a n ic u la tu m D e fl a n d re a o e b is fe ld e n si s T h a la ss ip h o ra d e lic a ta A p e ct o d in iu m h o m o m o rp h u m ? ? ? ? ? ? ? ? Dinoflagellate Cysts E C re t. L A lb . (V) (V1) P 6 b A . a u g u st u m N P 9 - N P 1 0 N P 1 1 - U . N P 1 0 N P 1 1 - ? N P 1 2 clay silt sand ? ? ? ? pebbl.clay silt gnl. sand Cross bedding Cross lamination Wavy and flaser bedding Erosive contact Clay and coal clast Sandstone Mudstone Muddy sandstone Basalt Conglomerate Lithology Planar lamination Sedimentary structures ? 220 ? ? ? g ?? L .. T h an e ti an - ? E . Y p re si an L . T h an e ti an - ? E . Y p re si an ? ? 1 2 3 4 A. augustum top E . D an ia n - ? E . S e la n d ia n A B Fault West East with the Paleocene–Eocene thermal maximum (PETM) which occurred at about 56 Ma and lasted for c. 170 kyr (Harding et al. 2011). The upper, coarser-grained part only yielded two dinocyst species Cerodinium sp. and Areoligera sp. and no nannofossils. The upper unit consists of more than 20 m of dark grey silty and sandy mud overlain by slightly heterolithic, fine- grained sand (22 m), fine-grained sand (10 m), conglomer- ate and pebbly sandstone (8 m) topped by a few metres of sand, mud and carbonaceous mud or coal. The palynologi- Fig. 2. A: Southern slope and fault at Haredal. The highest mountain is c. 700 m high. B: Sedimentological logs and range charts of selected in situ dinocysts and calcareous nannofossils. Numerals in the zones of the northern slope are: 1: Alisocysta margarita Zone, 2: Senegalinium iterlaaense Zone or Palaeo- cystodinium bulliforme Zone, 3: Trithyrodinium evittii Zone and 4: Spongodinium delitiense Subzone (Nøhr-Hansen et al. 2002). NA: Nannofossils, NP: Palaeogene nannoplankton zone. V, V1: Subtilisphaera kalaalliti Zone and Wigginsiella grandstandica Subzone (Nøhr-Hansen 1993). 63 cal assemblages below the conglomerate are dominated by reworked material of mid – Late Cretaceous age and a few specimens of Paleocene age. The succession is of early Ypre- sian (Early Eocene) age based on poorly preserved specimens of the dinocysts Apectodinum augustum, Apectodinium pan- iculatum, Def landrea oebisfeldensis and the nannofossil Tri- brachiatus orthostylus (Fig. 3). Samples above the conglomer- ate yielded a few reworked Upper Cretaceous and Paleocene dinocysts together with a few indeterminate algae and the nannofossil Helicosphaera seminulum (Fig. 3). The latter in- dicates an age not younger than mid Ypresian for the young- est dated sediments in Haredal; this is compatable with a mid Ypresian radiometric 39Ar/40Ar age of 55.02 ± 0.49 Ma for the oldest lava analysed from Wollaston Forland (L.M. Larsen personal communication 2008). Haredal northern slope. Approximately 180 m of sediments were studied on the northern slope of Haredal (Fig 1). The lower 40 m consist of dark grey mud with a palynological assemblage dominated by reworked material from mid – Up- per Cretaceous strata (e.g. Hapsocysta benteae, Chatangiella spp. and Aquilapollenites spp.). The presence of Trithyrodin- ium evittii, Spongodinium delitiense and a few specimens of Senoniasphaera inornata in the two lowermost samples indi- cates an Early Paleocene age and may correlate with the low- er Danian Trithyrodinium evittii Zone (Fig. 2) established from West Greenland (Nøhr-Hansen et al. 2002). The pres- ence of common Senegalinium iterlaaense and Palaeocysto- dinium bulliforme in the two overlying samples indicates a mid to late Danian age correlating with the Senegalinium iterlaaense and Palaeocystodinium bulliforme zones (2 and 3 in Fig. 2), whereas the next sample contains a few speci- mens of the dinocysts Alisocysta margarita and Cerodinium striatum indicating a late Danian/?early Selandian age cor- relating with the Alisocysta margarita Zone (Nøhr-Hansen et al. 2002; 1 in Fig. 2). The upper 130 m of sand and mud contain very few in situ palynomorphs, however the presence of Apectodinium augustum indicates correlation with the Apectodinium augustum (P6b) Subzone, indicating an ?early Selandian – Thanetian hiatus. Outer Haredal, Dronning Augusta Dal and Sabine Ø. Palaeo- gene sediments from the southern slope of the easternmost part of Haredal, on the eastern slope of Dronning Augusta Dal, and on the north-eastern slope of Harebjerg, Sabine Ø were also studied and sampled (Fig. 1).The successions all contain the PETM dinocyst marker Apectodinium augustum. North-eastern Hold with Hope Langsiden. Interbedded in dark grey mud at Langsiden (Fig. 1) occurs an 8 m thick unit with sharp-based, upward- fining successions of conglomerate and pebbly sand, up to a few metres thick containing large reworked mudstone clasts. The palynological assemblage from the underlying mud is dominated by a reworked f lora of late Maastrichtian age indicated by the presence of Triblastula wilsonii and Wode- houseia octospina. The presence of in situ Trithyrodinium evittii, Spongodinium delitiense and a few specimens of Se- noniasphaera inornata indicates correlation with the lower Danian Trithyrodinium evittii Zone (Nøhr-Hansen et al. 2002). The mudstone clasts yielded a mid Cretaceous f lo- ra. The palynomorph assemblage of two samples from the overlying mud is likewise dominated by a reworked Upper Cretaceous f lora; however, the lower sample also contains a few specimens of the dinocysts Alisocysta margarita and Cerodinium striatum, indicating correlation with the upper Danian/?lower Selandian Alisocysta margarita Zone (Nøhr- Hansen et al. 2002). The presence of Thalassiphora delicata in the upper sample indicates a latest Danian/early Selandian age (Nøhr-Hansen & Piasecki 2002). East of Fosdalen. Approximately 6 m of loose, white-grey, fine- to medium-grained sand with scattered small clay clasts 1 42A 2B 3 65 987 10 20 μm 20 μm 20 μm 20 μm 20 μm 20 μm 20 μm 2 μm2 μm2 μm20 μm Fig. 3. Images of selected dinocysts (1–7) and nannofossils (8–10). 1: Tri- thyrodinium evittii. 2A, B: Alisocysta margarita. 3: Thalassiphora delicata. 4: Gen et sp. indet. of Piasecki et al. (1992). 5: Apectodinium augustum. 6: Apectodinium paniculatum. 7: Def landrea oebisfeldensis. 8: Discoaster gem- meus? 9: Helicosphaera seminulum. 10: Tribrachiatus orthostylus. 6464 overlain by a less than 2 m thick bed of dark grey mud cov- ered by volcanic rocks overlies mid Cretaceous sandy mud- stone east of Fosdalen (Fig. 1). The palynological assemblage of the mud bed is dominated by spores and pollen and some reworked dinocysts of mid to Late Cretaceous age. In situ specimens of the dinocyst gen. et sp. indet. of Piasecki et al. (1992; Fig. 3) also occur, suggesting fresh to brackish water. The species is common in wells offshore eastern Canada just above the Apectodinium augustum P6b Subzone (H. Nøhr- Hansen, unpublished data). The occurrence of the species immediately below the basalts may indicate an earliest Ypre- sian age. Discussion The new biostratigraphic dating shows that the Palaeogene sediments on Wollaston Forland, Hold with Hope and Sa- bine Ø comprise Paleocene and earliest Eocene strata with a hiatus that probably spans the major part of the Selandian and Thanetian. The age of the underlying Cretaceous depos- its east of the fault in Haredal is Early–Middle Campanian, much younger than the Middle Albian previously described from Wollaston Forland (Nøhr-Hansen 1993). The strati- graphic gap between the Cretaceous and Palaeogene sedi- ments thus decreases towards the basin to the east. The large amount of reworked Cretaceous marine palynomorphs in- cluding a Late Maastrichtian f lora documents uplift of Cre- taceous marine sediments and major erosion during the Early Palaeogene. The ages of the youngest Palaeogene sediments and the oldest f lood basalts appear to be almost identical; however, the nature of the contact between the sediments and basalts needs to be further investigated to determine whether the contact is angular, as is suggested in places by a relatively steep dip of the sediments. Discontinuous conglomerate beds with rounded quartz- ite pebbles and boulders up to 20 cm, as well as cross-bedded sandstones, terminate the upper unit in Haredal and are in- terpreted as f luvial channel deposits. The absence of basaltic clasts indicates that deposition occurred prior to the volcan- ic events. The thin overlying succession with a coaly bed is interpreted as an aggrading coastal plain subject to marine inundations. However, the principal part of the Palaeogene sediments accumulated in a marine environment as indicat- ed by marine dinocysts and the presence of scattered marine trace fossils. Thin, fine-grained sandstone beds with f lute casts and a massive lower part overlain by beds with parallel lamination and cross-lamination in outer Haredal indicate deposition from turbidite currents. The sharp-based, fining- upward conglomerate beds and pebbly sand from Langsiden embedded in mud are interpreted as channelised gravity f low deposits. The two upward-coarsening units in Haredal sug- gest that the Palaeogene sediments mainly accumulated dur- ing two major depositional phases. Potential by-pass surfaces are identified at the Cretaceous–Palaeogene boundary, at the top of the lower unit, at the base of the f luvial conglome- rates and possibly at the sediment–basalt boundary. Coarse- grained sediments may have been transported toward the basin area to the east along these surfaces. 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