Journal cover Journal topic
Solid Earth An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

IF value: 2.921
IF2.921
IF 5-year value: 3.087
IF 5-year
3.087
CiteScore value: 4.8
CiteScore
4.8
SNIP value: 1.314
SNIP1.314
IPP value: 2.87
IPP2.87
SJR value: 0.993
SJR0.993
Scimago H <br class='widget-line-break'>index value: 38
Scimago H
index
38
h5-index value: 36
h5-index36
Preprints
https://doi.org/10.5194/se-2020-165
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/se-2020-165
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

  19 Oct 2020

19 Oct 2020

Review status
This preprint is currently under review for the journal SE.

Early Cenozoic Eurekan strain partitioning and decoupling in central Spitsbergen, Svalbard

Jean-Baptiste P. Koehl1,2,3,4 Jean-Baptiste P. Koehl
  • 1Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003 NMBU, NO-1432 Ås, Norway
  • 2Department of Geosciences, UiT The Arctic University of Norway in Tromsø, NO-9037 Tromsø, Norway
  • 3Research Centre for Arctic Petroleum Exploration (ARCEx), University of Tromsø, NO-9037 Tromsø, Norway
  • 4CAGE – Centre for Arctic Gas Hydrate, Environment and Climate, NO-9037 Tromsø, Norway

Abstract. The present study of field, petrological, exploration well and seismic data shows that backward-dipping duplexes comprised of phyllitic coal and bedding-parallel décollements and thrusts, which localized along lithological transitions in tectonically thickened Lower–lowermost Upper Devonian, uppermost Devonian–Mississippian and uppermost Pennsylvanian–lowermost Permian sedimentary strata of the Wood Bay and/or Widje Bay and/or Grey Hoek formations, of the Billefjorden Group and of the Wordiekammen Formation respectively, partially decoupled uppermost Devonian–Permian sedimentary rocks of the Billefjorden and Gipsdalen groups from Lower–lowermost Upper Devonian rocks of the Andrée Land Group and Mimerdalen Subgroup during early Cenozoic Eurekan deformation in central Spitsbergen. Eurekan strain decoupling along these structures explains differential deformation between Lower–lowermost Upper Devonian rocks of the Andrée Land Group/Mimerdalen Subgroup and overlying uppermost Devonian–Permian sedimentary strata of the Billefjorden and Gipsdalen groups in central–northern Spitsbergen without requiring an episode of (Ellesmerian) contraction in the Late Devonian. Potential formation mechanisms for bedding-parallel décollements and thrusts include shortcut faulting, and/or formation as a roof décollement in a fault-bend hanging wall (or ramp) anticline, as an imbricate fan, as an antiformal thrust stack, and/or as fault-propagation folds over reactivated/overprinted basement-seated faults. The interpretation of seismic data in Reindalspasset indicates that Devonian sedimentary rocks of the Andrée Land Group and Mimerdalen Subgroup might be preserved east of the Billefjorden Fault Zone, suggesting that the Billefjorden Fault Zone did not accommodate reverse movement in the Late Devonian. Hence, the thrusting of Proterozoic basement rocks over Lower Devonian sedimentary rocks along the Balliolbreen Fault and fold structures within strata of the Andrée Land Group and Mimerdalen Subgroup in central Spitsbergen may be explained by a combination of down-east Carboniferous normal faulting with associated footwall rotation and exhumation, and subsequent top-west early Cenozoic Eurekan thrusting along the Billefjorden Fault Zone. Finally, the study shows that major east-dipping faults, like the Billefjorden Fault Zone, may consists of several, discrete, unconnected (soft-linked and/or stepping) or, most probably, offset fault segments that were reactivated/overprinted with varying degree during Eurekan deformation due to strain partitioning and/or decoupling along sub-orthogonal NNE-dipping reverse faults.

Jean-Baptiste P. Koehl

Interactive discussion

Status: open (until 02 Jan 2021)
Status: open (until 02 Jan 2021)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement

Jean-Baptiste P. Koehl

Data sets

Replication data for: Devonian–Mississippian collapse and core complex exhumation, and partial decoupling and partitioning of Eurekan deformation as alternatives to the Ellesmerian Orogeny in Spitsbergen Jean-Baptiste P. Koehl https://doi.org/10.18710/MXKQPE

Jean-Baptiste P. Koehl

Viewed

Total article views: 257 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
221 28 8 257 15 1 5
  • HTML: 221
  • PDF: 28
  • XML: 8
  • Total: 257
  • Supplement: 15
  • BibTeX: 1
  • EndNote: 5
Views and downloads (calculated since 19 Oct 2020)
Cumulative views and downloads (calculated since 19 Oct 2020)

Viewed (geographical distribution)

Total article views: 237 (including HTML, PDF, and XML) Thereof 237 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 

Cited

Saved

No saved metrics found.

Discussed

No discussed metrics found.
Latest update: 30 Nov 2020
Publications Copernicus
Download
Short summary
This contribution shows that soft and coal-rich sedimentary rocks in central Spitsbergen absorbed most of the (Eurekan) contractional deformation that occurred in the early Cenozoic using seismic data and fieldwork, thus suggesting that no contractional deformation event is needed in the Late Devonian to explain the deformation differences among late Paleozoic sedimentary rocks. It also shows that the Billefjorden Fault Zone, a major crack in the Earth crust in Svalbard, is probably segmented.
This contribution shows that soft and coal-rich sedimentary rocks in central Spitsbergen...
Citation