Late Wenlock graptolite-bearing tuffaceous sandstone from Bornholm, Denmark
Late Wenlock (Silurian) graptoliferous dark grey mudstone and tuffaceous sandstone lithofacies occur, mainly as loose boulders, at the southeast coast of Bornholm. The mudstone may be estimated to repre-sent a 25 m thick sequence, and contains a graptolite fauna indicating the Cyrtograptus lundgreni...
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ftciteseerx:oai:CiteSeerX.psu:10.1.1.494.8296 2023-05-15T16:13:03+02:00 Late Wenlock graptolite-bearing tuffaceous sandstone from Bornholm, Denmark Merete Bjerreskov Karl Åge Jørgensen The Pennsylvania State University CiteSeerX Archives application/pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.494.8296 http://2dgf.dk/xpdf/bull31-03-04-129-149.pdf en eng http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.494.8296 http://2dgf.dk/xpdf/bull31-03-04-129-149.pdf Metadata may be used without restrictions as long as the oai identifier remains attached to it. http://2dgf.dk/xpdf/bull31-03-04-129-149.pdf text ftciteseerx 2016-01-08T08:42:56Z Late Wenlock (Silurian) graptoliferous dark grey mudstone and tuffaceous sandstone lithofacies occur, mainly as loose boulders, at the southeast coast of Bornholm. The mudstone may be estimated to repre-sent a 25 m thick sequence, and contains a graptolite fauna indicating the Cyrtograptus lundgreni Zone. The fauna is correlated with sequences of similar age from other areas, specially from Scania. Monograp-tus flemingi and Pristiograptus dubius pseudodubius are virtually the only species in the tuffaceous sandstone, some of which were deposited by turbidity currents. There is evidence from the taphonomy and diversity of the sandstone graptolites to suggest that the two species lived at a lower level in the water column than other, coexisting species. Size-frequency analyses are inconclusive as to whether or not the fauna in the tuffaceous sandstone represents a rapidly buried life-assemblage. The tuffaceous sandstone samples represent at least 3 airfall water deposited tuff beds and one bed deposited by turbidity current action. Mineral composition and grain-size of the tuffaceous sandstone indicate an origin from plinian eruptions at an estimated distance of about 300 km from Bornholm, and deposition at a depth of 1000 m ± 300 m, on the outer rim of the Fennoscandian platform. The volcanoes were probably situated on a continent south of Bornholm. The eruption centre later may either have disappeared within the Caledo-nian foldbelt or have been displaced by early Palaeozoic large-scale strike-slip faults towards the SE, along the SW border of the East-European craton. Text Fennoscandian Unknown |
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English |
description |
Late Wenlock (Silurian) graptoliferous dark grey mudstone and tuffaceous sandstone lithofacies occur, mainly as loose boulders, at the southeast coast of Bornholm. The mudstone may be estimated to repre-sent a 25 m thick sequence, and contains a graptolite fauna indicating the Cyrtograptus lundgreni Zone. The fauna is correlated with sequences of similar age from other areas, specially from Scania. Monograp-tus flemingi and Pristiograptus dubius pseudodubius are virtually the only species in the tuffaceous sandstone, some of which were deposited by turbidity currents. There is evidence from the taphonomy and diversity of the sandstone graptolites to suggest that the two species lived at a lower level in the water column than other, coexisting species. Size-frequency analyses are inconclusive as to whether or not the fauna in the tuffaceous sandstone represents a rapidly buried life-assemblage. The tuffaceous sandstone samples represent at least 3 airfall water deposited tuff beds and one bed deposited by turbidity current action. Mineral composition and grain-size of the tuffaceous sandstone indicate an origin from plinian eruptions at an estimated distance of about 300 km from Bornholm, and deposition at a depth of 1000 m ± 300 m, on the outer rim of the Fennoscandian platform. The volcanoes were probably situated on a continent south of Bornholm. The eruption centre later may either have disappeared within the Caledo-nian foldbelt or have been displaced by early Palaeozoic large-scale strike-slip faults towards the SE, along the SW border of the East-European craton. |
author2 |
The Pennsylvania State University CiteSeerX Archives |
format |
Text |
author |
Merete Bjerreskov Karl Åge Jørgensen |
spellingShingle |
Merete Bjerreskov Karl Åge Jørgensen Late Wenlock graptolite-bearing tuffaceous sandstone from Bornholm, Denmark |
author_facet |
Merete Bjerreskov Karl Åge Jørgensen |
author_sort |
Merete Bjerreskov |
title |
Late Wenlock graptolite-bearing tuffaceous sandstone from Bornholm, Denmark |
title_short |
Late Wenlock graptolite-bearing tuffaceous sandstone from Bornholm, Denmark |
title_full |
Late Wenlock graptolite-bearing tuffaceous sandstone from Bornholm, Denmark |
title_fullStr |
Late Wenlock graptolite-bearing tuffaceous sandstone from Bornholm, Denmark |
title_full_unstemmed |
Late Wenlock graptolite-bearing tuffaceous sandstone from Bornholm, Denmark |
title_sort |
late wenlock graptolite-bearing tuffaceous sandstone from bornholm, denmark |
url |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.494.8296 http://2dgf.dk/xpdf/bull31-03-04-129-149.pdf |
genre |
Fennoscandian |
genre_facet |
Fennoscandian |
op_source |
http://2dgf.dk/xpdf/bull31-03-04-129-149.pdf |
op_relation |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.494.8296 http://2dgf.dk/xpdf/bull31-03-04-129-149.pdf |
op_rights |
Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
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1765998658034073600 |