Advanced

The Cambrian–Ordovician succession at Lanna, Sweden : stratigraphy and depositional environments

Lindskog, Anders LU ; Lindskog, Anna M. L. ; Johansson, Jan V.; Ahlberg, Per LU and Eriksson, Mats LU (2018) In Estonian Journal of Earth Sciences 67(2). p.133-148
Abstract
A ca 20 m thick succession of upper Furongian (Cambrian Stage 10) through Middle Ordovician (Darriwilian) strata exposed at Lanna, in the province of Närke, south-central Sweden, is described. The upper Furongian is represented by the Alum Shale Formation and reflects an overall shallowing trend that ultimately resulted in emergence above sea level and subaerial conditions. Hence, as in most other areas in south-central Sweden, the boundary between the Cambrian and the Ordovician is marked by a prominent disconformity and significant hiatus. In Närke, the hiatus spans the middle Stage 10 through the uppermost Tremadocian or lowermost Floian. The presence of stromatolites indicates quite shallow marine conditions during the latest Cambrian.... (More)
A ca 20 m thick succession of upper Furongian (Cambrian Stage 10) through Middle Ordovician (Darriwilian) strata exposed at Lanna, in the province of Närke, south-central Sweden, is described. The upper Furongian is represented by the Alum Shale Formation and reflects an overall shallowing trend that ultimately resulted in emergence above sea level and subaerial conditions. Hence, as in most other areas in south-central Sweden, the boundary between the Cambrian and the Ordovician is marked by a prominent disconformity and significant hiatus. In Närke, the hiatus spans the middle Stage 10 through the uppermost Tremadocian or lowermost Floian. The presence of stromatolites indicates quite shallow marine conditions during the latest Cambrian. The Ordovician succession is characterized by flatly bedded ‘orthoceratite limestone’, belonging to the ‘Latorp’, ‘Lanna’ and ‘Holen’ limestones (‘topoformations’). Widely varying microfacies characteristics in the ‘orthoceratite limestone’ suggest that the depositional environment underwent substantial changes through time, largely due to changes in sea level. A long-term trend of coarsening carbonate textures and more diverse fossil assemblages is seen upwards through the Ordovician succession. Cyclic microfacies patterns probably reflect high-frequency sea-level changes. Comparisons to other parts of Sweden and Baltoscandia reveal consistent patterns in the sedimentary development across a wide geographical area. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Carbonate sedimentology, Microfacies, Palaeoecology, Palaeoenvironment, Baltoscandia
in
Estonian Journal of Earth Sciences
volume
67
issue
2
pages
133 - 148
publisher
Estonian Academy Publishers
external identifiers
  • scopus:85047554258
ISSN
1736-7557
DOI
10.3176/earth.2018.10
language
English
LU publication?
yes
id
f7521d58-d4dc-433c-8a99-789638a6f657
date added to LUP
2019-03-02 22:12:18
date last changed
2019-10-15 06:59:19
@article{f7521d58-d4dc-433c-8a99-789638a6f657,
  abstract     = {A ca 20 m thick succession of upper Furongian (Cambrian Stage 10) through Middle Ordovician (Darriwilian) strata exposed at Lanna, in the province of Närke, south-central Sweden, is described. The upper Furongian is represented by the Alum Shale Formation and reflects an overall shallowing trend that ultimately resulted in emergence above sea level and subaerial conditions. Hence, as in most other areas in south-central Sweden, the boundary between the Cambrian and the Ordovician is marked by a prominent disconformity and significant hiatus. In Närke, the hiatus spans the middle Stage 10 through the uppermost Tremadocian or lowermost Floian. The presence of stromatolites indicates quite shallow marine conditions during the latest Cambrian. The Ordovician succession is characterized by flatly bedded ‘orthoceratite limestone’, belonging to the ‘Latorp’, ‘Lanna’ and ‘Holen’ limestones (‘topoformations’). Widely varying microfacies characteristics in the ‘orthoceratite limestone’ suggest that the depositional environment underwent substantial changes through time, largely due to changes in sea level. A long-term trend of coarsening carbonate textures and more diverse fossil assemblages is seen upwards through the Ordovician succession. Cyclic microfacies patterns probably reflect high-frequency sea-level changes. Comparisons to other parts of Sweden and Baltoscandia reveal consistent patterns in the sedimentary development across a wide geographical area.},
  author       = {Lindskog, Anders and Lindskog, Anna M. L.  and Johansson, Jan V. and Ahlberg, Per and Eriksson, Mats},
  issn         = {1736-7557},
  keyword      = {Carbonate sedimentology,Microfacies,Palaeoecology,Palaeoenvironment,Baltoscandia},
  language     = {eng},
  month        = {04},
  number       = {2},
  pages        = {133--148},
  publisher    = {Estonian Academy Publishers},
  series       = {Estonian Journal of Earth Sciences},
  title        = {The Cambrian–Ordovician succession at Lanna, Sweden : stratigraphy and depositional environments},
  url          = {http://dx.doi.org/10.3176/earth.2018.10},
  volume       = {67},
  year         = {2018},
}