Pub Date : 2020-07-28DOI: 10.37570/bgsd-2019-67-02
Kai Ingemann Schnetler
Spinucella reimersi in the Late Miocene Gram Clay, Denmark The mica-rich clay at Gram in southern Denmark (Fig. 1) has been known since 1848, and digging of a pit for brick-making started after 1857 (L.B. Rasmussen 1968, p. 10). The collecting of molluscs started soon thereafter, and Semper (1861) studied material from Gram. Further studies in the second half of the 19th century, including material from Gram, were made by von Koenen (1872, 1882) and Mörch (1874). A description of the geological setting of the Gram Clay is found in E.S. Rasmussen (2005). For further references to the fauna, see Schnetler (2005). The physician Martin Reimers started as a general practitioner in Gram in 1841 and was a keen and skillful collector of fossils in the clay pit; without doubt this caught the interest of the professional palaeontologists. Carinastarte vetula reimersi (Ravn 1907), the most common mollusc species in the Gram Clay, was named in honour of Martin Reimers by Semper in an unpublished manuscript. The present study describes Martin Reimers’ connection to a very rare and almost neglected gastropod species, Spinucella reimersi, which since the first finding in 1862 has only been encountered twice. Furthermore, two new specimens have allowed an emended description of the species.
{"title":"On the occurrence of Spinucella reimersi (von Koenen 1872) (Gastropoda: Muricidae) in the Late Miocene Gram Clay of Denmark, and an emended description of the species","authors":"Kai Ingemann Schnetler","doi":"10.37570/bgsd-2019-67-02","DOIUrl":"https://doi.org/10.37570/bgsd-2019-67-02","url":null,"abstract":"Spinucella reimersi in the Late Miocene Gram Clay, Denmark The mica-rich clay at Gram in southern Denmark (Fig. 1) has been known since 1848, and digging of a pit for brick-making started after 1857 (L.B. Rasmussen 1968, p. 10). The collecting of molluscs started soon thereafter, and Semper (1861) studied material from Gram. Further studies in the second half of the 19th century, including material from Gram, were made by von Koenen (1872, 1882) and Mörch (1874). A description of the geological setting of the Gram Clay is found in E.S. Rasmussen (2005). For further references to the fauna, see Schnetler (2005). The physician Martin Reimers started as a general practitioner in Gram in 1841 and was a keen and skillful collector of fossils in the clay pit; without doubt this caught the interest of the professional palaeontologists. Carinastarte vetula reimersi (Ravn 1907), the most common mollusc species in the Gram Clay, was named in honour of Martin Reimers by Semper in an unpublished manuscript. The present study describes Martin Reimers’ connection to a very rare and almost neglected gastropod species, Spinucella reimersi, which since the first finding in 1862 has only been encountered twice. Furthermore, two new specimens have allowed an emended description of the species.","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":"67 1","pages":"23-27"},"PeriodicalIF":1.2,"publicationDate":"2020-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44377145","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 : 2020-07-27DOI: 10.37570/bgsd-2019-67-01
U. Gregersen, P. Knutz, H. Nøhr-Hansen, E. Sheldon, J. Hopper
Large structural highs and sedimentary basins are identified from mapping of the West Greenland continental margin from the Labrador Sea to the Baffin Bay. We present a new tectonic elements map and a map of thickness from the seabed to the basement of the entire West Greenland margin. In addition, a new stratigraphic scheme of the main lithologies and tectonostratigraphy based on ties to all offshore exploration wells is presented together with seven interpreted seismic sections. The work is based on interpretation of more than 135 000 km of 2D seismic reflection data supported by other geophysical data, including gravity- and magnetic data and selected 3D seismic data, and is constrained by correlation to wells and seabed samples. Eight seismic mega-units (A–H) from the seabed to the basement, related to distinct tectonostratigraphic phases, were mapped. The oldest units include pre-rift basins that contain Proterozoic and Palaeozoic successions. Cretaceous syn-rift phases are characterised by development of large extensional fault blocks and basins with wedge-shaped units. The basin strata include Cretaceous and Palaeogene claystones, sandstones and conglomerates. During the latest Cretaceous, Paleocene and Eocene, crustal extension followed by oceanic crust formation took place, causing separation of the continental margins of Greenland and Canada with north-east to northward movement of Greenland. From Paleocene to Eocene, volcanic rocks dominated the central West Greenland continental margin and covered the Cretaceous basins. Development of the oceanic crust is associated with compressional tectonics and the development of strike-slip and thrust faults, pull-apart basins and inversion structures, most pronounced in the Davis Strait and Baffin Bay regions. During the late Cenozoic, tectonism diminished, though some intra-plate vertical adjustments occurred. The latest basin development was characterised by formation of thick Neogene to Quaternary marine successions including contourite drifts and glacial related shelf progradation towards the west and south-west.
{"title":"Tectonostratigraphy and evolution of the West Greenland continental margin","authors":"U. Gregersen, P. Knutz, H. Nøhr-Hansen, E. Sheldon, J. Hopper","doi":"10.37570/bgsd-2019-67-01","DOIUrl":"https://doi.org/10.37570/bgsd-2019-67-01","url":null,"abstract":"Large structural highs and sedimentary basins are identified from mapping of the West Greenland continental margin from the Labrador Sea to the Baffin Bay. We present a new tectonic elements map and a map of thickness from the seabed to the basement of the entire West Greenland margin. In addition, a new stratigraphic scheme of the main lithologies and tectonostratigraphy based on ties to all offshore exploration wells is presented together with seven interpreted seismic sections. The work is based on interpretation of more than 135 000 km of 2D seismic reflection data supported by other geophysical data, including gravity- and magnetic data and selected 3D seismic data, and is constrained by correlation to wells and seabed samples. Eight seismic mega-units (A–H) from the seabed to the basement, related to distinct tectonostratigraphic phases, were mapped. The oldest units include pre-rift basins that contain Proterozoic and Palaeozoic successions. Cretaceous syn-rift phases are characterised by development of large extensional fault blocks and basins with wedge-shaped units. The basin strata include Cretaceous and Palaeogene claystones, sandstones and conglomerates. During the latest Cretaceous, Paleocene and Eocene, crustal extension followed by oceanic crust formation took place, causing separation of the continental margins of Greenland and Canada with north-east to northward movement of Greenland. From Paleocene to Eocene, volcanic rocks dominated the central West Greenland continental margin and covered the Cretaceous basins. Development of the oceanic crust is associated with compressional tectonics and the development of strike-slip and thrust faults, pull-apart basins and inversion structures, most pronounced in the Davis Strait and Baffin Bay regions. During the late Cenozoic, tectonism diminished, though some intra-plate vertical adjustments occurred. The latest basin development was characterised by formation of thick Neogene to Quaternary marine successions including contourite drifts and glacial related shelf progradation towards the west and south-west.","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":"67 1","pages":"1-21"},"PeriodicalIF":1.2,"publicationDate":"2020-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46937287","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 : 2020-07-05DOI: 10.37570/bgsd-2019-67-03
I. Møller, N. Balling, C. Ditlefsen
Shallow subsurface thermal structure onshore Denmark Subsurface temperatures and thermal properties are important factors in controlling the amount of thermal energy that can be extracted or stored in the ground. Local and regional variations in the thermal conditions affect the design and efficiency of shallow geothermal installations, especially when heat pumps are applied (Rasmussen et al. 2016; Sanner 2016). Thus, knowledge about temperature, subsurface thermal properties as well as heat flow are required for estimating geothermal resources and in evaluating methodologies for heat extraction. In contrast to deep geothermal conditions (cf. Balling et al. 1992, 2002; Mathiesen et al. 2009, 2010), until the present study, the shallow subsurface thermal conditions in Denmark have not been analysed on a national scale. The first borehole temperatures were measured around 1900 as accurate bottom hole temperatures (Bonnesen et al. 1913) while the, at the time, deepest Shallow subsurface thermal structure onshore Denmark: temperature, thermal conductivity and heat flow
{"title":"Shallow subsurface thermal structure onshore Denmark: temperature, thermal conductivity and heat flow","authors":"I. Møller, N. Balling, C. Ditlefsen","doi":"10.37570/bgsd-2019-67-03","DOIUrl":"https://doi.org/10.37570/bgsd-2019-67-03","url":null,"abstract":"Shallow subsurface thermal structure onshore Denmark Subsurface temperatures and thermal properties are important factors in controlling the amount of thermal energy that can be extracted or stored in the ground. Local and regional variations in the thermal conditions affect the design and efficiency of shallow geothermal installations, especially when heat pumps are applied (Rasmussen et al. 2016; Sanner 2016). Thus, knowledge about temperature, subsurface thermal properties as well as heat flow are required for estimating geothermal resources and in evaluating methodologies for heat extraction. In contrast to deep geothermal conditions (cf. Balling et al. 1992, 2002; Mathiesen et al. 2009, 2010), until the present study, the shallow subsurface thermal conditions in Denmark have not been analysed on a national scale. The first borehole temperatures were measured around 1900 as accurate bottom hole temperatures (Bonnesen et al. 1913) while the, at the time, deepest Shallow subsurface thermal structure onshore Denmark: temperature, thermal conductivity and heat flow","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":"67 1","pages":"29-52"},"PeriodicalIF":1.2,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47775595","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 : 2020-06-26DOI: 10.37570/bgsd-2020-68-07
S. Piasecki, J. Bojesen‐Koefoed, P. Alsen
New data on the Lower Cretaceous Falskebugt Member (Palnatokes Bjerg Formation) and Stratumbjerg Formation in easternmost Wollaston Forland, northern East Greenland, are interpreted here. The type locality of the Falskebugt Member on the north-west corner of the Falkebjerg ridge has been revisited, and additional new good exposures were found in a riverbed just north of Falkebjerg and more in river beds on the plain further to the north, where both the Falskebugt Member and the Stratumbjerg Formation are exposed. Previously, only a limited marine fauna was reported providing a restricted middle Valanginian age of the Falskebugt Member. New fossil faunas in other parts of the Falskebugt Member suggest an early Valanginian – Hauterivian age and confirm lateral correlation with the Albrechts Bugt and Rødryggen Members of the Palnatokes Bjerg Formation. However, in places where the Falskebugt Member is exposed in contact with the lower Stratumbjerg Formation, dinoflagellate cysts from these units indicate Barremian and late Barremian ages, respectively. The stratigraphic range of the combined biostratigraphic data from the Falskebugt Member indicates an early Valanginian – late Barremian age. Dinoflagellate cysts from part of the assemblage in the Stratumbjerg Formation suggest a marginal marine/brackish water depositional environment. Comparable depositional environments are also recorded in upper Barremian sediments on Store Koldewey and in the Ladegårdsåen Formation on Peary Land much farther to the north in Greenland. The dark mudstones of the Stratumbjerg Formation show no potential for generation of liquid hydrocarbons, and the immature and poorly sorted sediments of the Falskebugt Member have little potential as a petroleum reservoir.
{"title":"Geology of the Lower Cretaceous in the Falkebjerg area, Wollaston Forland, northern East Greenland","authors":"S. Piasecki, J. Bojesen‐Koefoed, P. Alsen","doi":"10.37570/bgsd-2020-68-07","DOIUrl":"https://doi.org/10.37570/bgsd-2020-68-07","url":null,"abstract":"New data on the Lower Cretaceous Falskebugt Member (Palnatokes Bjerg Formation) and Stratumbjerg Formation in easternmost Wollaston Forland, northern East Greenland, are interpreted here. The type locality of the Falskebugt Member on the north-west corner of the Falkebjerg ridge has been revisited, and additional new good exposures were found in a riverbed just north of Falkebjerg and more in river beds on the plain further to the north, where both the Falskebugt Member and the Stratumbjerg Formation are exposed. Previously, only a limited marine fauna was reported providing a restricted middle Valanginian age of the Falskebugt Member. New fossil faunas in other parts of the Falskebugt Member suggest an early Valanginian – Hauterivian age and confirm lateral correlation with the Albrechts Bugt and Rødryggen Members of the Palnatokes Bjerg Formation. However, in places where the Falskebugt Member is exposed in contact with the lower Stratumbjerg Formation, dinoflagellate cysts from these units indicate Barremian and late Barremian ages, respectively. The stratigraphic range of the combined biostratigraphic data from the Falskebugt Member indicates an early Valanginian – late Barremian age. Dinoflagellate cysts from part of the assemblage in the Stratumbjerg Formation suggest a marginal marine/brackish water depositional environment. Comparable depositional environments are also recorded in upper Barremian sediments on Store Koldewey and in the Ladegårdsåen Formation on Peary Land much farther to the north in Greenland. The dark mudstones of the Stratumbjerg Formation show no potential for generation of liquid hydrocarbons, and the immature and poorly sorted sediments of the Falskebugt Member have little potential as a petroleum reservoir.","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46252125","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 : 2020-06-12DOI: 10.37570/bgsd-2020-68-06
Lisa Pasquinelli, M. Felder, M. Gulbrandsen, T. Hansen, Jun-Seo Jeon, N. Molenaar, K. Mosegaard, I. Fabricius
Heat storage in the Danish subsurface is gaining increasing interest for optimizing the use of energy resources, but no deep heat storage facilities have yet been established. As an analogue we study the Gassum Formation in the Stenlille structure that is presently used for gas storage. This allows us to discuss geological and technical characteristics of an aquifer relevant for heat storage in Denmark. We develop a 3D model for a high-temperature aquifer thermal energy storage system using analysis of geological core data, sedimentological description, geophysical data including well logs and seismic lines, as well as a finite difference model to calculate the recovery efficiency, heat storage capacity and thermal breakthrough time. Based on geostatistical methods we made three realisations and found similar results for the three cases. In accordance with results from published simplified models we found a high recovery efficiency of 70% after 4 years and 69% after 20 years, a high heat storage capacity of 1.8×1018 J, and a long thermal breakthrough time of 66–77 years. These results reflect the excellent reservoir properties of the Gassum Formation in Stenlille, characterised by a uniformly layered sand/shale sedimentology, a high average porosity of 25% and a high permeability of 1000 to 10 000 mD of sandstone intervals.
{"title":"The feasibility of high-temperature aquifer thermal energy storage in Denmark: the Gassum Formation in the Stenlille structure","authors":"Lisa Pasquinelli, M. Felder, M. Gulbrandsen, T. Hansen, Jun-Seo Jeon, N. Molenaar, K. Mosegaard, I. Fabricius","doi":"10.37570/bgsd-2020-68-06","DOIUrl":"https://doi.org/10.37570/bgsd-2020-68-06","url":null,"abstract":"Heat storage in the Danish subsurface is gaining increasing interest for optimizing\u0000the use of energy resources, but no deep heat storage facilities have yet been\u0000established. As an analogue we study the Gassum Formation in the Stenlille\u0000structure that is presently used for gas storage. This allows us to discuss geological\u0000and technical characteristics of an aquifer relevant for heat storage in Denmark.\u0000We develop a 3D model for a high-temperature aquifer thermal energy storage system\u0000using analysis of geological core data, sedimentological description, geophysical\u0000data including well logs and seismic lines, as well as a finite difference model to\u0000calculate the recovery efficiency, heat storage capacity and thermal breakthrough\u0000time. Based on geostatistical methods we made three realisations and found similar\u0000results for the three cases. In accordance with results from published simplified\u0000models we found a high recovery efficiency of 70% after 4 years and 69% after 20\u0000years, a high heat storage capacity of 1.8×1018 J, and a long thermal breakthrough\u0000time of 66–77 years. These results reflect the excellent reservoir properties of the\u0000Gassum Formation in Stenlille, characterised by a uniformly layered sand/shale\u0000sedimentology, a high average porosity of 25% and a high permeability of 1000 to\u000010 000 mD of sandstone intervals.","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42758397","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 : 2020-06-05DOI: 10.37570/bgsd-2020-68-05
L. Clemmensen, Dennis Kent, M. Mau, O. Mateus, J. Milán
The lithostratigraphy of the Triassic deposits of the Jameson Land Basin in central East Greenland is revised. The new Scoresby Land Supergroup is now composed of the Wordie Creek, Pingo Dal, Gipsdalen and Fleming Fjord Groups. This paper only deals with the lithostratigraphy of the late Early-Late Triassic continental deposits of the latter three groups with emphasis on the vertebratebearing Fleming Fjord Group. The new Pingo Dal Group consists of three new formations, the Rødstaken, Paradigmabjerg and Klitdal Formations (all elevated from members), the new Gipsdalen Group consists of three new formations, the Kolledalen, Solfaldsdal (with the new Gråklint Member) and Kap Seaforth Formations (all elevated from members), and the new Fleming Fjord Group is subdivided into three new formations, the Edderfugledal, Malmros Klint and Ørsted Dal Formations (all elevated from members). The Edderfugledal Formation contains two cyclic bedded, lacustrine members, a lowermost Sporfjeld Member (elevated from beds), and an uppermost Pingel Dal Member (elevated from beds). The lacustrine red beds of the Malmros Klint Formation are not subdivided. The lacustrine and fluvial Ørsted Dal Formation contains three new members. In the eastern and central part of the basin, the formation is initiated by cyclic bedded, red lacustrine mudstones of the Carlsberg Fjord Member (elevated from beds), while in the northwestern part of the basin the lowermost part of the formation is composed of grey fluvial conglomerates and sandstones with subordinate red mudstones of the Bjergkronerne Member (elevated from beds). The uppermost part of the formations in most of the basin is composed of cyclic bedded, variegated lacustrine mudstones and grey to yellowish marlstones of the Tait Bjerg Member (elevated from beds). The sediments in the Fleming Fjord Group contain remains of a rich and diverse vertebrate fauna including dinosaurs, amphibians, turtles, aeotosaurs, pterosaurs, phytosaurs and mammaliaforms. Most vertebrate bones have been found in uppermost Malmros Klint Formation, and in the Carlsberg Fjord and Tait Bjerg Members. The Norian–early Rhaetian, lacustrine Fleming Fjord Group was deposited at about 41° N on the northern part of the supercontinent Pangaea. Lacustrine sedimentation was controlled by seasonal as well as longer-term (orbital) variation in precipitation. Precipitation was probably brought to the basin by southwesterly winds. The lacustrine sediments of the uppermost Fleming Fjord Group show deposition during increasingly humid conditions changing the lake environment from an ephemeral lake-steppe area to a perennial lake. This evolution of lake environment suggests a change from a winter-wet temperate climate to one with precipitation throughout the year.
{"title":"Triassic lithostratigraphy of the Jameson Land Basin (central East\u0000Greenland), with emphasis on the new Fleming Fjord Group","authors":"L. Clemmensen, Dennis Kent, M. Mau, O. Mateus, J. Milán","doi":"10.37570/bgsd-2020-68-05","DOIUrl":"https://doi.org/10.37570/bgsd-2020-68-05","url":null,"abstract":"The lithostratigraphy of the Triassic deposits of the Jameson Land Basin in\u0000central East Greenland is revised. The new Scoresby Land Supergroup is now\u0000composed of the Wordie Creek, Pingo Dal, Gipsdalen and Fleming Fjord Groups.\u0000This paper only deals with the lithostratigraphy of the late Early-Late Triassic\u0000continental deposits of the latter three groups with emphasis on the vertebratebearing\u0000Fleming Fjord Group. The new Pingo Dal Group consists of three new\u0000formations, the Rødstaken, Paradigmabjerg and Klitdal Formations (all elevated\u0000from members), the new Gipsdalen Group consists of three new formations,\u0000the Kolledalen, Solfaldsdal (with the new Gråklint Member) and Kap Seaforth\u0000Formations (all elevated from members), and the new Fleming Fjord Group is\u0000subdivided into three new formations, the Edderfugledal, Malmros Klint and\u0000Ørsted Dal Formations (all elevated from members). The Edderfugledal Formation\u0000contains two cyclic bedded, lacustrine members, a lowermost Sporfjeld Member\u0000(elevated from beds), and an uppermost Pingel Dal Member (elevated from beds).\u0000The lacustrine red beds of the Malmros Klint Formation are not subdivided. The\u0000lacustrine and fluvial Ørsted Dal Formation contains three new members. In the\u0000eastern and central part of the basin, the formation is initiated by cyclic bedded,\u0000red lacustrine mudstones of the Carlsberg Fjord Member (elevated from beds),\u0000while in the northwestern part of the basin the lowermost part of the formation\u0000is composed of grey fluvial conglomerates and sandstones with subordinate red\u0000mudstones of the Bjergkronerne Member (elevated from beds). The uppermost part\u0000of the formations in most of the basin is composed of cyclic bedded, variegated\u0000lacustrine mudstones and grey to yellowish marlstones of the Tait Bjerg Member\u0000(elevated from beds). The sediments in the Fleming Fjord Group contain remains\u0000of a rich and diverse vertebrate fauna including dinosaurs, amphibians, turtles,\u0000aeotosaurs, pterosaurs, phytosaurs and mammaliaforms. Most vertebrate bones\u0000have been found in uppermost Malmros Klint Formation, and in the Carlsberg\u0000Fjord and Tait Bjerg Members. The Norian–early Rhaetian, lacustrine Fleming\u0000Fjord Group was deposited at about 41° N on the northern part of the supercontinent\u0000Pangaea. Lacustrine sedimentation was controlled by seasonal as well as\u0000longer-term (orbital) variation in precipitation. Precipitation was probably brought\u0000to the basin by southwesterly winds. The lacustrine sediments of the uppermost\u0000Fleming Fjord Group show deposition during increasingly humid conditions\u0000changing the lake environment from an ephemeral lake-steppe area to a perennial\u0000lake. This evolution of lake environment suggests a change from a winter-wet\u0000temperate climate to one with precipitation throughout the year.","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41469957","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 : 2020-04-25DOI: 10.37570/bgsd-2020-68-04
M. Bjerager, P. Alsen, J. Bojesen‐Koefoed, M. Fyhn, J. Hovikoski, J. Ineson, H. Nøhr-Hansen, L. Nielsen, S. Piasecki, H. Vosgerau
An updated and revised lithostratigraphic scheme is presented for the Cretaceous of North-East Greenland from Traill Ø in the south to Store Koldewey in the north. The Ryazanian to lower Maastrichtian succession is up to several kilometres thick and comprises four groups, 12 formations and 18 members. The groups record the tectonic evolution of the East Greenland depocentre on the western flank of the evolving proto-Atlantic seaway. The Wollaston Forland Group encompasses the uppermost Jurassic – lowermost Cretaceous rift-climax succession and contains the Lindemans Bugt and Palnatokes Bjerg Formations; two new members of the latter formation are erected from Store Koldewey. Post-rift Cretaceous strata are referred to the new Brorson Halvø Group and the Home Forland Group. The Brorson Halvø Group (uppermost Hauterivian – middle Albian) is dominated by slope and basinal mudstones of the new Stratumbjerg Formation but also includes fluvio-deltaic and shallow marine sandstones of the revised Steensby Bjerg Formation on northern Hold with Hope and submarine slope apron breccias and conglomerates of the revised Rold Bjerge Formation on Traill Ø. The Home Forland Group covers the middle Albian – Coniacian succession. The basal unconformity records an important mid-Albian tectonic event involving intrabasinal uplift, tilting and erosion, as exemplified by the middle Albian conglomerates of the new Kontaktravine Formation on Clavering Ø. The Home Forland Group is dominated regionally by mud-dominated slope to basinal deposits of the elevated and revised Fosdalen Formation; it also includes lowstand basin-floor fan sandstones of the new upper Albian Langsiden Member. The new Jackson Ø Group (upper Turonian – lower Maastrichtian), records a phase of basin reorganisation marked by a significant fall in sedimentation rate in North-East Greenland, probably linked to rift events in, and bypass to, the central proto-Atlantic rift system. The base of the group is an erosional unconformity on Traill Ø and Geographical Society Ø overlain by submarine slope-apron conglomerates of the Turonian Månedal Formation. The base is conformable on Hold with Hope but is defined by a condensed interval (the Coniacian Nanok Member) that is succeeded conformably by slope and basin-floor turbidite sandstones of the Coniacian–Santonian Østersletten Formation and slope to basinal mudstones of the Campanian – lower Maastrichtian Knudshoved Formation. The new Leitch Bjerg Formation of Campanian slope-apron conglomerates and sandstones in eastern Geographical Society Ø erosionally overlies the Knudshoved Formation.
提出了一个更新和修订的格陵兰东北部白垩纪岩石地层方案，从南部的Traillæ到北部的Store Koldewey。梁赞阶至下马斯特里赫特阶层序厚达数公里，由四组、12个地层和18个成员组成。这些群记录了东格陵兰沉积中心的构造演化，该沉积中心位于演化中的原大西洋海道的西侧。Wollaston Forland群包含侏罗纪最上层-白垩纪最下层的裂谷高潮序列，并包含Lindemans Bugt和Palnatokes Bjerg组；后一个编队的两个新成员从Store Koldewey竖立起来。裂谷后白垩纪地层被称为新的Broson-Halvø群和Home-Forland群。Broson-Halvø群（最上层的豪特里夫阶-中阿尔比安阶）以新Stratumjerg组的斜坡和盆地泥岩为主，但也包括北部Hold with Hope改良后的Steensby Bjerg组中的河流三角洲和浅海砂岩，以及Traillæ改良后的Rold Bjerg地层中的海底斜坡护角砾岩和砾岩。主场福兰组覆盖了阿尔比亚-科尼亚奇中期的继承。基底不整合记录了一个重要的阿尔布期中期构造事件，涉及盆地内隆起、倾斜和侵蚀，例如克拉弗林上新Kontaktravine组的阿尔布阶中期砾岩。Home-Forland群在区域上以泥质为主，斜坡至盆地沉积为抬升和修正的Fosdalen组；还包括新上阿尔比安-朗西顿段低位盆底扇砂岩。新的杰克逊群（上土仑阶-下马斯特里赫特阶）记录了一个盆地重组阶段，其特征是格陵兰东北部沉积速率显著下降，可能与中央原大西洋裂谷系的裂谷事件有关，并绕过该裂谷系。该群的底部是Traill和Geographical Society上的侵蚀不整合面，上面覆盖着Turonian Månedal组的海底斜坡护坦砾岩。基底在Hold with Hope上是一致的，但由一个浓缩层段（Coniacian Nanok段）定义，该浓缩层段由Coniacian-SantonianÖstersletten组的斜坡和盆底浊积砂岩以及Campanian-lower Maastrichtian Knudshoved组的斜坡至盆地泥岩一致继承。东部地理学会的Campanian斜坡护坦砾岩和砂岩的新Leitch Bjerg组在侵蚀上覆盖在Knudshoved组上。
{"title":"Cretaceous lithostratigraphy of North-East Greenland","authors":"M. Bjerager, P. Alsen, J. Bojesen‐Koefoed, M. Fyhn, J. Hovikoski, J. Ineson, H. Nøhr-Hansen, L. Nielsen, S. Piasecki, H. Vosgerau","doi":"10.37570/bgsd-2020-68-04","DOIUrl":"https://doi.org/10.37570/bgsd-2020-68-04","url":null,"abstract":"An updated and revised lithostratigraphic scheme is presented for the Cretaceous of North-East Greenland from Traill Ø in the south to Store Koldewey in the north. The Ryazanian to lower Maastrichtian succession is up to several kilometres thick and comprises four groups, 12 formations and 18 members. The groups record the tectonic evolution of the East Greenland depocentre on the western flank of the evolving proto-Atlantic seaway. The Wollaston Forland Group encompasses the uppermost Jurassic – lowermost Cretaceous rift-climax succession and contains the Lindemans Bugt and Palnatokes Bjerg Formations; two new members of the latter formation are erected from Store Koldewey. Post-rift Cretaceous strata are referred to the new Brorson Halvø Group and the Home Forland Group. The Brorson Halvø Group (uppermost Hauterivian – middle Albian) is dominated by slope and basinal mudstones of the new Stratumbjerg Formation but also includes fluvio-deltaic and shallow marine sandstones of the revised Steensby Bjerg Formation on northern Hold with Hope and submarine slope apron breccias and conglomerates of the revised Rold Bjerge Formation on Traill Ø. The Home Forland Group covers the middle Albian – Coniacian succession. The basal unconformity records an important mid-Albian tectonic event involving intrabasinal uplift, tilting and erosion, as exemplified by the middle Albian conglomerates of the new Kontaktravine Formation on Clavering Ø. The Home Forland Group is dominated regionally by mud-dominated slope to basinal deposits of the elevated and revised Fosdalen Formation; it also includes lowstand basin-floor fan sandstones of the new upper Albian Langsiden Member. The new Jackson Ø Group (upper Turonian – lower Maastrichtian), records a phase of basin reorganisation marked by a significant fall in sedimentation rate in North-East Greenland, probably linked to rift events in, and bypass to, the central proto-Atlantic rift system. The base of the group is an erosional unconformity on Traill Ø and Geographical Society Ø overlain by submarine slope-apron conglomerates of the Turonian Månedal Formation. The base is conformable on Hold with Hope but is defined by a condensed interval (the Coniacian Nanok Member) that is succeeded conformably by slope and basin-floor turbidite sandstones of the Coniacian–Santonian Østersletten Formation and slope to basinal mudstones of the Campanian – lower Maastrichtian Knudshoved Formation. The new Leitch Bjerg Formation of Campanian slope-apron conglomerates and sandstones in eastern Geographical Society Ø erosionally overlies the Knudshoved Formation.","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41985619","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 : 2020-04-01DOI: 10.37570/bgsd-2020-68-03
B. Schulz, Madeleine L. Vickers, J. Huggett, H. Madsen, C. Heilmann-Clausen, H. Friis, E. Suess
Pristinely preserved mineral pseudomorphs called glendonites, up to 1.6 m long, from the Palaeogene strata of Denmark allow detailed crystallographic characterisation and add to the understanding of the transformation of the precursor mineral, ikaite (CaCO3·6H2O), to calcite, which constitutes the glendonite. We describe Danish pseudomorphs after ikaite from two localities and formations: the Early Eocene Fur Formation and the Late Oligocene Brejning Formation. This detailed study highlights that key aspects such as morphology and mode of occurrence of these ancient glendonites are identical to those of their parent mineral ikaite, when it grows in marine sediments. Systematic distortion of the angles in glendonite and marine sedimentary ikaite relative to the ideal ikaite symmetry may arise due to the incorporation of organic matter into the crystal structure, and we demonstrate the similarity between modern and ancient ikaite formation zones in the marine sedimentary realm with respect to organic matter.
{"title":"Palaeogene glendonites from Denmark","authors":"B. Schulz, Madeleine L. Vickers, J. Huggett, H. Madsen, C. Heilmann-Clausen, H. Friis, E. Suess","doi":"10.37570/bgsd-2020-68-03","DOIUrl":"https://doi.org/10.37570/bgsd-2020-68-03","url":null,"abstract":"Pristinely preserved mineral pseudomorphs called glendonites, up to 1.6 m long, from the Palaeogene strata of Denmark allow detailed crystallographic characterisation and add to the understanding of the transformation of the precursor mineral, ikaite (CaCO3·6H2O), to calcite, which constitutes the glendonite. We describe Danish pseudomorphs after ikaite from two localities and formations: the Early Eocene Fur Formation and the Late Oligocene Brejning Formation. This detailed study highlights that key aspects such as morphology and mode of occurrence of these ancient glendonites are identical to those of their parent mineral ikaite, when it grows in marine sediments. Systematic distortion of the angles in glendonite and marine sedimentary ikaite relative to the ideal ikaite symmetry may arise due to the incorporation of organic matter into the crystal structure, and we demonstrate the similarity between modern and ancient ikaite formation zones in the marine sedimentary realm with respect to organic matter.","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49292613","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 : 2020-03-13DOI: 10.37570/bgsd-2020-68-02
Ebbe Nyborg, F. Surlyk, N. Thibault
An atlante is a corbel figure (or pillar support) sculpted in the form of a man carrying a heavy load. A group of well-preserved stone carved atlantes from c. 1250 carrying the vaults of the Ribe Cathedral in western Jylland, Denmark, represents the antique titan Atlas and are up to 150 cm high. Their obviously foreign origin has so far remained uncertain. The figures are made of a relatively soft, sandy limestone. A new nannofossil analysis of small chips of the chalky and sandy limestone narrows the age of the stone down to the late Campanian (Late Cretaceous). Upper Campanian sandy limestones of this type are exposed in the Münster Basin in North Rhine-Westphalia, western Germany. The Campanian Baumberger Sandstein in this region fits well with the atlantes in terms of lithology and age and is the only possible provenance of the stone. Around 1250 the Baumberger Sandstein was used for baptismal fonts as far north as Ostfriesland at the Dutch-German border, and it is a novel finding of this investigation that it even reached Denmark. The stone was most likely floated along the rivers Lippe and Rhine and shipped via the Wadden Sea to Ribe. It is a remarkably long transport distance for historic commercial stone transportation in continental northern European art in the High Middle Ages.
{"title":"Provenance of Medieval atlantes in the Ribe Cathedral, Denmark, based on geological and palaeontological investigations","authors":"Ebbe Nyborg, F. Surlyk, N. Thibault","doi":"10.37570/bgsd-2020-68-02","DOIUrl":"https://doi.org/10.37570/bgsd-2020-68-02","url":null,"abstract":"An atlante is a corbel figure (or pillar support) sculpted in the form of a man carrying\u0000a heavy load. A group of well-preserved stone carved atlantes from c. 1250 carrying\u0000the vaults of the Ribe Cathedral in western Jylland, Denmark, represents the antique\u0000titan Atlas and are up to 150 cm high. Their obviously foreign origin has so far remained\u0000uncertain. The figures are made of a relatively soft, sandy limestone. A new\u0000nannofossil analysis of small chips of the chalky and sandy limestone narrows the age\u0000of the stone down to the late Campanian (Late Cretaceous). Upper Campanian sandy\u0000limestones of this type are exposed in the Münster Basin in North Rhine-Westphalia,\u0000western Germany. The Campanian Baumberger Sandstein in this region fits well\u0000with the atlantes in terms of lithology and age and is the only possible provenance\u0000of the stone. Around 1250 the Baumberger Sandstein was used for baptismal fonts\u0000as far north as Ostfriesland at the Dutch-German border, and it is a novel finding of\u0000this investigation that it even reached Denmark. The stone was most likely floated\u0000along the rivers Lippe and Rhine and shipped via the Wadden Sea to Ribe. It is a\u0000remarkably long transport distance for historic commercial stone transportation in\u0000continental northern European art in the High Middle Ages.","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46549131","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 : 2020-03-09DOI: 10.37570/bgsd-2020-68-01
J. S. Peel
A small fauna of middle Cambrian trilobites is described from the upper Telt Bugt Formation of Daugaard-Jensen Land, western North Greenland, and the formation is formally defined. Blainiopsis holt ...
{"title":"Middle Cambrian trilobites (Miaolingian, Ehmaniella Biozone) from the Telt Bugt Formation of Daugaard-Jensen Land, western North Greenland","authors":"J. S. Peel","doi":"10.37570/bgsd-2020-68-01","DOIUrl":"https://doi.org/10.37570/bgsd-2020-68-01","url":null,"abstract":"A small fauna of middle Cambrian trilobites is described from the upper Telt Bugt Formation of Daugaard-Jensen Land, western North Greenland, and the formation is formally defined. Blainiopsis holt ...","PeriodicalId":55310,"journal":{"name":"Bulletin of the Geological Society of Denmark","volume":"68 1","pages":"1-14"},"PeriodicalIF":1.2,"publicationDate":"2020-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69890258","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：