Pub Date : 2021-05-31DOI: 10.37570/BGSD-2021-69-04
Tom J. Giltaij, V. Jeroen, B. Lindow, A. Schulp, J. Jagt
The carbon stable isotope composition (δ13C) of tooth enamel in mosasaurid squa-mates reflects aspects of their diet and diving behaviour. Here we present new δ13C data for such marine squamates from the Maastrichtian of Denmark and compare these with results obtained in previous studies from the lower-latitude type area of the Maastrichtian Stage (latest Cretaceous; 72.1–66.0 Ma) in the south-east Nether-lands and north-east Belgium. For the Danish samples, there is a weak correlation between mosasaur body size and δ13C values, with larger-sized taxa having lower δ13C values, comparable to what has previously been observed for mosasaurs from the Maastrichtian type area.
{"title":"Carbon isotope trends in north-west European mosasaurs (Squamata; Late Cretaceous)","authors":"Tom J. Giltaij, V. Jeroen, B. Lindow, A. Schulp, J. Jagt","doi":"10.37570/BGSD-2021-69-04","DOIUrl":"https://doi.org/10.37570/BGSD-2021-69-04","url":null,"abstract":"The carbon stable isotope composition (δ13C) of tooth enamel in mosasaurid squa-mates reflects aspects of their diet and diving behaviour. Here we present new δ13C data for such marine squamates from the Maastrichtian of Denmark and compare these with results obtained in previous studies from the lower-latitude type area of the Maastrichtian Stage (latest Cretaceous; 72.1–66.0 Ma) in the south-east Nether-lands and north-east Belgium. For the Danish samples, there is a weak correlation between mosasaur body size and δ13C values, with larger-sized taxa having lower δ13C values, comparable to what has previously been observed for mosasaurs from the Maastrichtian type area.","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":"69 1","pages":"59-70"},"PeriodicalIF":1.2,"publicationDate":"2021-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42649050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-02-23DOI: 10.37570/BGSD-2021-69-02
W. Schwarzhans, J. Milán, G. Carnevale
The ichnofossil Lepidenteron provides a unique taphonomic window into the life habits of a tube-dwelling predator, probably an eunicid polychaete, and its fish prey. Here we describe a new tube-like ichnofossil Lepidenteron mortenseni n. isp. from the Kerteminde Marl (100–150 m palaeo-water depth) from the Gundstrup gravel pit near Odense, Fyn, Denmark. 110 individual tubes were examined which contain fish remains, including a variety of disarticulated bones and otoliths, by far dominated by a single gadiform taxon referred herein to as Bobbitichthys n. gen. The isolated otoliths here associated with disarticulated gadiform bones have previously been described, from the time equivalent Lellinge Greensand exposed in the Copenhagen area, as Hymenocephalus rosenkrantzi, a grenadier fish (family Macrouridae). The abundance of associated bones and otoliths in the examined tubes allowed us to reconstruct part of the cranial configuration of Bobbitichthys rosenkrantzi and to tentatively interpret it as a stem macrourid. Bobbitichthys rosenkrantzi represents the earliest grenadier known in the fossil record. Additional, although considerably less abundant, skeletal remains and otoliths have been tentatively referred to a long-fin bonefish (family Pterothrissidae, Pterothrissus? conchaeformis), a viviparous brotula (family Bythitidae, Bidenichthys? lapierrei), a conger eel (family Congridae, possibly belonging to Rhynchoconger angulosus), and another unidentified gadiform.
{"title":"A tale from the middle Paleocene of Denmark: A tube-dwelling predator documented by the ichnofossil Lepidenteron mortenseni n. isp. and its predominant prey, Bobbitichthys n. gen. rosenkrantzi (Macroridae, Teleostei)","authors":"W. Schwarzhans, J. Milán, G. Carnevale","doi":"10.37570/BGSD-2021-69-02","DOIUrl":"https://doi.org/10.37570/BGSD-2021-69-02","url":null,"abstract":"The ichnofossil Lepidenteron provides a unique taphonomic window into the life habits of a tube-dwelling predator, probably an eunicid polychaete, and its fish prey. Here we describe a new tube-like ichnofossil Lepidenteron mortenseni n. isp. from the Kerteminde Marl (100–150 m palaeo-water depth) from the Gundstrup gravel pit near Odense, Fyn, Denmark. 110 individual tubes were examined which contain fish remains, including a variety of disarticulated bones and otoliths, by far dominated by a single gadiform taxon referred herein to as Bobbitichthys n. gen. The isolated otoliths here associated with disarticulated gadiform bones have previously been described, from the time equivalent Lellinge Greensand exposed in the Copenhagen area, as Hymenocephalus rosenkrantzi, a grenadier fish (family Macrouridae). The abundance of associated bones and otoliths in the examined tubes allowed us to reconstruct part of the cranial configuration of Bobbitichthys rosenkrantzi and to tentatively interpret it as a stem macrourid. Bobbitichthys rosenkrantzi represents the earliest grenadier known in the fossil record. Additional, although considerably less abundant, skeletal remains and otoliths have been tentatively referred to a long-fin bonefish (family Pterothrissidae, Pterothrissus? conchaeformis), a viviparous brotula (family Bythitidae, Bidenichthys? lapierrei), a conger eel (family Congridae, possibly belonging to Rhynchoconger angulosus), and another unidentified gadiform.","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":"69 1","pages":"35-52"},"PeriodicalIF":1.2,"publicationDate":"2021-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43190867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-20DOI: 10.37570/BGSD-2021-69-01
J. S. Peel
Trilobites dominantly of middle Cambrian (Miaolingian Series, Wuliuan Stage) age are described from the Telt Bugt Formation of Daugaard-Jensen Land, western North Greenland (Laurentia), which is a correlative of the Cape Wood Formation of Inglefield Land and Ellesmere Island, Nunavut. Four biozones are recognised in Daugaard-Jensen Land, representing the Delamaran and Topazan regional stages of the western USA. The basal Plagiura–Poliella Biozone, with Mexicella cf. robusta, Kochiella, Fieldaspis? and Plagiura?, straddles the Cambrian Series 2–Miaolingian Series boundary. It is overlain by the Mexicella mexicana Biozone, recognised for the first time in Greenland, with rare specimens of Caborcella arrojosensis. The Glossopleura walcotti Biozone, with Glossopleura, Clavaspidella and Polypleuraspis, dominates the succession in eastern Daugaard-Jensen Land but is seemingly not represented in the type section in western outcrops, likely reflecting the drastic thinning of the formation towards the north-west. The Ehmaniella Biozone, with Ehmaniella, Clappaspsis, Blainia and Blainiopsis, is the youngest recognised biozone. The presence of Drumian Stage strata reported elsewhere in North Greenland and adjacent Ellesmere Island has not been confirmed in Daugaard-Jensen Land. Lower beds of the Cass Fjord Formation, which directly overlie the Telt Bugt Formation, are assigned to the Guzhangian Stage. New species: Fieldaspis? iubilaei, Ehmaniella tupeqarfik.
{"title":"Trilobite fauna of the Telt Bugt Formation (Cambrian Series 2–Miaolingian Series), western North Greenland (Laurentia)","authors":"J. S. Peel","doi":"10.37570/BGSD-2021-69-01","DOIUrl":"https://doi.org/10.37570/BGSD-2021-69-01","url":null,"abstract":"Trilobites dominantly of middle Cambrian (Miaolingian Series, Wuliuan Stage) age are described from the Telt Bugt Formation of Daugaard-Jensen Land, western North Greenland (Laurentia), which is a correlative of the Cape Wood Formation of Inglefield Land and Ellesmere Island, Nunavut.\u0000\u0000Four biozones are recognised in Daugaard-Jensen Land, representing the Delamaran and Topazan regional stages of the western USA. The basal Plagiura–Poliella Biozone, with Mexicella cf. robusta, Kochiella, Fieldaspis? and Plagiura?, straddles the Cambrian Series 2–Miaolingian Series boundary. It is overlain by the Mexicella mexicana Biozone, recognised for the first time in Greenland, with rare specimens of Caborcella arrojosensis. The Glossopleura walcotti Biozone, with Glossopleura, Clavaspidella and Polypleuraspis, dominates the succession in eastern Daugaard-Jensen Land but is seemingly not represented in the type section in western outcrops, likely reflecting the drastic thinning of the formation towards the north-west. The Ehmaniella Biozone, with Ehmaniella, Clappaspsis, Blainia and Blainiopsis, is the youngest recognised biozone. The presence of Drumian Stage strata reported elsewhere in North Greenland and adjacent Ellesmere Island has not been confirmed in Daugaard-Jensen Land. Lower beds of the Cass Fjord Formation, which directly overlie the Telt Bugt Formation, are assigned to the Guzhangian Stage. New species: Fieldaspis? iubilaei, Ehmaniella tupeqarfik.","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":"69 1","pages":"1-33"},"PeriodicalIF":1.2,"publicationDate":"2021-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42324577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.37570/BGSD-2011-59-03
G. Mayr
Morsoravis sedilis is a small bird from the early Eocene Fur Formation of Denmark, which in the original description was considered to be most closely related to Charadriiformes. Because Morsoravis has subsequently been likened to Pumiliornis tesselatus, an equally enigmatic bird from the middle Eocene of Messel in Germany, I perform here the first phylogenetic analysis including the two taxa. This analysis supports a sister group relationship between Morsoravis and Pumiliornis, and the clade including the two taxa is recovered as the sister taxon of the late Eocene/early Oligocene Eocuculus. I report a possible, albeit lost, second specimen of Morsoravis, and identify derived characters in support of a sister group relationship between Morsoravis and Pumiliornis. The analysis did not resolve the higher-level affinities of the clade including Morsoravis, Pumiliornis, and Eocuculus, and did not confirm charadriiform affinities of Morsoravis. More data on the osteology of the fossils, as well as an improved understanding of the interrelationships of extant birds, are needed for a well-established phylogenetic assignment of these fossil taxa.
{"title":"On the osteology and phylogenetic affinities of Morsoravis sedilis (Aves) from the early Eocene Fur Formation of Denmark","authors":"G. Mayr","doi":"10.37570/BGSD-2011-59-03","DOIUrl":"https://doi.org/10.37570/BGSD-2011-59-03","url":null,"abstract":"Morsoravis sedilis is a small bird from the early Eocene Fur Formation of Denmark, which in the original description was considered to be most closely related to Charadriiformes. Because Morsoravis has subsequently been likened to Pumiliornis tesselatus, an equally enigmatic bird from the middle Eocene of Messel in Germany, I perform here the first phylogenetic analysis including the two taxa. This analysis supports a sister group relationship between Morsoravis and Pumiliornis, and the clade including the two taxa is recovered as the sister taxon of the late Eocene/early Oligocene Eocuculus. I report a possible, albeit lost, second specimen of Morsoravis, and identify derived characters in support of a sister group relationship between Morsoravis and Pumiliornis. The analysis did not resolve the higher-level affinities of the clade including Morsoravis, Pumiliornis, and Eocuculus, and did not confirm charadriiform affinities of Morsoravis. More data on the osteology of the fossils, as well as an improved understanding of the interrelationships of extant birds, are needed for a well-established phylogenetic assignment of these fossil taxa.","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":"59 1","pages":"23-35"},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69889945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-17DOI: 10.37570/bgsd-2020-68-11
J. Milán, P. Falkingham, Inken Juliane Mueller-Töwe
Two new small tridactyl dinosaur tracks are found in the Middle Jurassic Bagå Formation of Bornholm and are interpreted as ornithopodian in origin. A skeletal fragment is identified as a crocodilian skull fragment. Previous finds of dinosaur tracks from the locality consist of two sizes of sauropods, a medium sized theropod and thyreophorans. The addition of tracks from ornithopod dinosaurs and skeletal evidence of crocodilians now give a broader picture of a diverse Middle Jurassic vertebrate fauna. This is an important addition to the understanding of the terres-trial Mesozoic ecosystem of Denmark, and a valuable addition to the scarce Middle Jurassic vertebrate record of Europe.
{"title":"Small ornithopod dinosaur tracks and crocodilian remains from the Middle Jurassic Bagå Formation, Bornholm, Denmark: Important additions to the rare Middle Jurassic vertebrate faunas of Northern Europe","authors":"J. Milán, P. Falkingham, Inken Juliane Mueller-Töwe","doi":"10.37570/bgsd-2020-68-11","DOIUrl":"https://doi.org/10.37570/bgsd-2020-68-11","url":null,"abstract":"Two new small tridactyl dinosaur tracks are found in the Middle Jurassic Bagå Formation of Bornholm and are interpreted as ornithopodian in origin. A skeletal fragment is identified as a crocodilian skull fragment. Previous finds of dinosaur tracks from the locality consist of two sizes of sauropods, a medium sized theropod and thyreophorans. The addition of tracks from ornithopod dinosaurs and skeletal evidence of crocodilians now give a broader picture of a diverse Middle Jurassic vertebrate fauna. This is an important addition to the understanding of the terres-trial Mesozoic ecosystem of Denmark, and a valuable addition to the scarce Middle Jurassic vertebrate record of Europe.","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49316173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-24DOI: 10.37570/bgsd-2019-67-07
P. Holm, Niels-Ole Prægel
The Kærven Syenite Complex (KSC) is one of the oldest felsic intrusions in the Tertiary East Greenland province. Here we update our previous description of the KSC and supply a greatly expanded and comprehensive geochemical dataset. New data allow us to present a more detailed petrogenetic model for the evolution of the KSC and to investigate the geochemical characteristics of igneous cumulates subjected to loss and, occasionally, replacement of residual liquid. The KSC comprises eleven mappable units that generally young westwards. Rock types range from quartz syenite to quartz alkali feldspar syenite and alkali feldspar granite. Individual intrusive units are relatively narrow and steep-sided and are collectively suggested to represent a ring dyke complex. Basement gneiss and gabbro host rocks have locally contaminated the oldest quartz syenite KSC unit, but most of the main part of the complex escaped significant influence from host rocks. A late suite of E–W to NE–SW striking peralkaline dykes of trachytic to phonolitic compositions intrude the KSC. Compositions of the KSC rocks span a considerable range in SiO2, 59–73 wt%. Concentrations of several elements vary widely for a given SiO2 (especially at SiO2 < 66 wt%), and variation diagrams do not suggest a single model for the evolution of the units of the complex. A cumulative origin is envisaged for several KSC units. Geochemical modelling suggests that KSC magmas were derived from more than one primary magma, and that the complex evolved through a four-stage process: fractional crystallisation in precursory magma chambers was followed by final emplacement of each unit, establishment of a crystal/melt mush, expulsion of part of the residual melt and, finally, crystallisation of the remaining melt. Trace element disequilibria between alkali feldspar and host rocks in two closely associated quartz alkali feldspar syenite units indicate that highly evolved residual melt was replaced by a less evolved melt phase. Modelling of potential parent melt compositions to the Kærven magmas suggests an origin not in the Iceland plume asthenosphere, but rather in a moderately enriched source, possibly in the continental lithosphere. The course of melt evolution by fractional crystallisation is indicated to have taken place in magma chambers at depth, and repeated rise of magma into the upper crustal magma chambers and crystallisation there formed the KSC. Based on our survey of published geochemical data, the inferred parental magmas seem to have few equivalents in the North Atlantic Igneous Province and may have been generated mainly from melting of enriched dry lithospheric mantle of possibly Archaean age.
{"title":"The importance of in situ crystallisation and loss of interstitial melt during formation of the Kærven Syenite Complex, Kangerlussuaq, East Greenland","authors":"P. Holm, Niels-Ole Prægel","doi":"10.37570/bgsd-2019-67-07","DOIUrl":"https://doi.org/10.37570/bgsd-2019-67-07","url":null,"abstract":"The Kærven Syenite Complex (KSC) is one of the oldest felsic intrusions in the Tertiary East Greenland province. Here we update our previous description of the KSC and supply a greatly expanded and comprehensive geochemical dataset. New data allow us to present a more detailed petrogenetic model for the evolution of the KSC and to investigate the geochemical characteristics of igneous cumulates subjected to loss and, occasionally, replacement of residual liquid. The KSC comprises eleven mappable units that generally young westwards. Rock types range from quartz syenite to quartz alkali feldspar syenite and alkali feldspar granite. Individual intrusive units are relatively narrow and steep-sided and are collectively suggested to represent a ring dyke complex. Basement gneiss and gabbro host rocks have locally contaminated the oldest quartz syenite KSC unit, but most of the main part of the complex escaped significant influence from host rocks. A late suite of E–W to NE–SW striking peralkaline dykes of trachytic to phonolitic compositions intrude the KSC. Compositions of the KSC rocks span a considerable range in SiO2, 59–73 wt%. Concentrations of several elements vary widely for a given SiO2 (especially at SiO2 < 66 wt%), and variation diagrams do not suggest a single model for the evolution of the units of the complex. A cumulative origin is envisaged for several KSC units. Geochemical modelling suggests that KSC magmas were derived from more than one primary magma, and that the complex evolved through a four-stage process: fractional crystallisation in precursory magma chambers was followed by final emplacement of each unit, establishment of a crystal/melt mush, expulsion of part of the residual melt and, finally, crystallisation of the remaining melt. Trace element disequilibria between alkali feldspar and host rocks in two closely associated quartz alkali feldspar syenite units indicate that highly evolved residual melt was replaced by a less evolved melt phase. Modelling of potential parent melt compositions to the Kærven magmas suggests an origin not in the Iceland plume asthenosphere, but rather in a moderately enriched source, possibly in the continental lithosphere. The course of melt evolution by fractional crystallisation is indicated to have taken place in magma chambers at depth, and repeated rise of magma into the upper crustal magma chambers and crystallisation there formed the KSC. Based on our survey of published geochemical data, the inferred parental magmas seem to have few equivalents in the North Atlantic Igneous Province and may have been generated mainly from melting of enriched dry lithospheric mantle of possibly Archaean age.","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44356909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-20DOI: 10.37570/bgsd-2020-68-10
O. Bennike, P. Pantmann, Esben Aarsleff
The Salpetermosen area in north-east Sjælland, Denmark, was deglaciated about 18 000 to 17 000 years ago. Melting of bodies of stagnant glacier ice led to the for-mation of kettle holes, which contain Lateglacial and Holocene sediments with remains of plants and animals that provide information on the past flora and fauna of the area. During the Allerød period, open forests with Betula pubescens (downy birch) characterised the area, the flora included light-demanding species such as Arctostaphylos uva-ursi (bearberry), Empetrum nigrum (crowberry) and rare Populus tremula (aspen), Betula nana (dwarf birch) and Rubus saxatilis (stone bramble), as well as the thermophilous swamp plant Oenanthe aquatica (fine-leaved water dropwort). During the Younger Dryas, the vegetation was characterised by dwarf-shrub heaths dominated by Betula nana, but including Dryas octopetala (mountain avens), Salix herbacea (least willow), Arctostaphylos alpina (alpine bearberry,) and rare Betula pube-scens, as well as the thermophilous plants Urtica dioeca (stinging nettle) and Lychnis flos-cuculi (ragged robin). The Early Holocene forests were dominated by Betula pubescens, Populus tremula and Pinus sylvestris (scots pine), but included rare Betula nana. Alnus glutinosa (alder) arrived at c. 10 000 cal. years BP. The calciphilous sedge Cladium mariscus (fen-sedge) and the macrolimnophyte Najas marina (spiny naiad) were common. The Late Holocene flora included the acidophilous plant Scheuchzeria palustris (rannoch-rush).
{"title":"Lateglacial and Holocene floras and faunas from the Salpetermosen area, north-east Sjælland, Denmark","authors":"O. Bennike, P. Pantmann, Esben Aarsleff","doi":"10.37570/bgsd-2020-68-10","DOIUrl":"https://doi.org/10.37570/bgsd-2020-68-10","url":null,"abstract":"The Salpetermosen area in north-east Sjælland, Denmark, was deglaciated about 18 000 to 17 000 years ago. Melting of bodies of stagnant glacier ice led to the for-mation of kettle holes, which contain Lateglacial and Holocene sediments with remains of plants and animals that provide information on the past flora and fauna of the area. During the Allerød period, open forests with Betula pubescens (downy birch) characterised the area, the flora included light-demanding species such as Arctostaphylos uva-ursi (bearberry), Empetrum nigrum (crowberry) and rare Populus tremula (aspen), Betula nana (dwarf birch) and Rubus saxatilis (stone bramble), as well as the thermophilous swamp plant Oenanthe aquatica (fine-leaved water dropwort).\u0000During the Younger Dryas, the vegetation was characterised by dwarf-shrub heaths dominated by Betula nana, but including Dryas octopetala (mountain avens), Salix herbacea (least willow), Arctostaphylos alpina (alpine bearberry,) and rare Betula pube-scens, as well as the thermophilous plants Urtica dioeca (stinging nettle) and Lychnis flos-cuculi (ragged robin).\u0000The Early Holocene forests were dominated by Betula pubescens, Populus tremula and Pinus sylvestris (scots pine), but included rare Betula nana. Alnus glutinosa (alder) arrived at c. 10 000 cal. years BP. The calciphilous sedge Cladium mariscus (fen-sedge) and the macrolimnophyte Najas marina (spiny naiad) were common. The Late Holocene flora included the acidophilous plant Scheuchzeria palustris (rannoch-rush).","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":"68 1","pages":"231-244"},"PeriodicalIF":1.2,"publicationDate":"2020-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45421396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-27DOI: 10.37570/bgsd-2019-67-05
J. S. Peel
The gastropods Sinuopea sp. and Lecanospira cf. compacta (Salter 1859) of probable early Ordovician age are described from cherty limestone clasts within fluvial strata of the Cretaceous Atane Form ...
{"title":"Ordovician gastropods from pebbles in Cretaceous fluvial\u0000sandstones in south-east Disko, West Greenland","authors":"J. S. Peel","doi":"10.37570/bgsd-2019-67-05","DOIUrl":"https://doi.org/10.37570/bgsd-2019-67-05","url":null,"abstract":"The gastropods Sinuopea sp. and Lecanospira cf. compacta (Salter 1859) of probable early Ordovician age are described from cherty limestone clasts within fluvial strata of the Cretaceous Atane Form ...","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":"67 1","pages":"75-81"},"PeriodicalIF":1.2,"publicationDate":"2020-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47847894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-14DOI: 10.37570/BGSD-2020-68-09
N. Schovsbo, L. Ponsaing, A. Mathiesen, J. Bojesen‐Koefoed, L. Kristensen, K. Dybkjær, P. Johannessen, F. Jakobsen, B. Peter
Schovsbo, N.H., Ponsaing, L., Mathiesen, A., Bojesen-Koefoed, J.A., Kristensen, L., Dybkjær, K., Johannessen, P., Jakobsen, F. & Britze, P. 2020. Regional hydrocarbon potential and thermal reconstruction of the Lower Jurassic to lowermost Cretaceous source rocks in the Danish Central Graben. Bulletin of the Geological Society of Denmark, Vol. 68, pp. 195–230. ISSN 2245-7070. https://doi.org/10.37570/bgsd-2020-68-09
{"title":"Regional hydrocarbon potential and thermal reconstruction of the Lower Jurassic to lowermost Cretaceous source rocks in the Danish Central Graben","authors":"N. Schovsbo, L. Ponsaing, A. Mathiesen, J. Bojesen‐Koefoed, L. Kristensen, K. Dybkjær, P. Johannessen, F. Jakobsen, B. Peter","doi":"10.37570/BGSD-2020-68-09","DOIUrl":"https://doi.org/10.37570/BGSD-2020-68-09","url":null,"abstract":"Schovsbo, N.H., Ponsaing, L., Mathiesen, A., Bojesen-Koefoed, J.A., Kristensen, L., Dybkjær, K., Johannessen, P., Jakobsen, F. & Britze, P. 2020. Regional hydrocarbon potential and thermal reconstruction of the Lower Jurassic to lowermost Cretaceous source rocks in the Danish Central Graben. Bulletin of the Geological Society of Denmark, Vol. 68, pp. 195–230. ISSN 2245-7070. https://doi.org/10.37570/bgsd-2020-68-09","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":"68 1","pages":"195-230"},"PeriodicalIF":1.2,"publicationDate":"2020-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46388996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-08-07DOI: 10.37570/bgsd-2020-68-08
Line Bayer Winslow, S. Pedersen, L. O. Boldreel, E. Nørmark
Wrench-fault structures below Danian limestone and Palaeogene marl, and an overlying structural framework of Quaternary glacial deposits in north-east Sjælland, Denmark, are interpreted from two vibro-seismic sections recorded to 600 msec TWT depth. The main seismic section is 6.3 km long, N–S oriented, and intersected by a 0.7 km long, E–W oriented satellite seismic section. In addition, boreholes in the vicinity of the seismic profile are used for the interpretation. The sections were acquired in 2014 along the western shoreline of the lake Esrum Sø in the Gribskov area. In the lower part of the seismic section (the interval 100–300 msec TWT), parallel-bedded geological layers occur along most of the profile apart from six locations, where six wrench-fault structures displace the upper part of the Chalk Group and lower Palaeogene marl. The northernmost of the six wrench-fault locations correlates to the eastern slope of the buried Esrum–Alnarp valley, which suggests that the valley is an inherited tectonic feature. The location of the wrench- fault structures supports the outline of faults related to the Sorgenfrei-Tornquist Zone on previous geological maps, which had almost no seismic data from the area. Above the stratigraphic level presented by the Danian limestone and lower Palaeogene marl, a composite glaciotectonic complex comprising two glaciodynamic sequences is recognized by e.g. thrust-fault structures and the lithostratigraphy of glacial successions recorded in the wells. In parts of the seismic sections, the lowermost level of the glaciotectonic complex inherited the wrench-tectonic fault structures, most significantly seen in the northern segment. The advance of the Scandinavian ice sheet caused the glaciotectonic structures displayed in the seismic section. The two sequences represent events related to the Norwegian and the Swedish glacial advances. From the interpretation of the seismic section it is found that the glaciotectonic complex conceals the wrench-tectonic flower structures.
{"title":"Wrench-fault structures superimposed by glaciotectonic complexes, interpreted from high-resolution reflection-seismic sections and boreholes along the western bank of Esrum Sø, north-east Sjælland, Denmark","authors":"Line Bayer Winslow, S. Pedersen, L. O. Boldreel, E. Nørmark","doi":"10.37570/bgsd-2020-68-08","DOIUrl":"https://doi.org/10.37570/bgsd-2020-68-08","url":null,"abstract":"Wrench-fault structures below Danian limestone and Palaeogene marl, and an overlying\u0000structural framework of Quaternary glacial deposits in north-east Sjælland,\u0000Denmark, are interpreted from two vibro-seismic sections recorded to 600 msec TWT\u0000depth. The main seismic section is 6.3 km long, N–S oriented, and intersected by a 0.7\u0000km long, E–W oriented satellite seismic section. In addition, boreholes in the vicinity\u0000of the seismic profile are used for the interpretation. The sections were acquired in\u00002014 along the western shoreline of the lake Esrum Sø in the Gribskov area. In the\u0000lower part of the seismic section (the interval 100–300 msec TWT), parallel-bedded\u0000geological layers occur along most of the profile apart from six locations, where six\u0000wrench-fault structures displace the upper part of the Chalk Group and lower Palaeogene\u0000marl. The northernmost of the six wrench-fault locations correlates to the\u0000eastern slope of the buried Esrum–Alnarp valley, which suggests that the valley is\u0000an inherited tectonic feature. The location of the wrench- fault structures supports\u0000the outline of faults related to the Sorgenfrei-Tornquist Zone on previous geological\u0000maps, which had almost no seismic data from the area.\u0000Above the stratigraphic level presented by the Danian limestone and lower Palaeogene\u0000marl, a composite glaciotectonic complex comprising two glaciodynamic\u0000sequences is recognized by e.g. thrust-fault structures and the lithostratigraphy\u0000of glacial successions recorded in the wells. In parts of the seismic sections, the\u0000lowermost level of the glaciotectonic complex inherited the wrench-tectonic fault\u0000structures, most significantly seen in the northern segment. The advance of the\u0000Scandinavian ice sheet caused the glaciotectonic structures displayed in the seismic\u0000section. The two sequences represent events related to the Norwegian and the\u0000Swedish glacial advances. From the interpretation of the seismic section it is found\u0000that the glaciotectonic complex conceals the wrench-tectonic flower structures.","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":"401 8","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41286465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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