Caledonian thrusting on Bjornoya: Implications for Palaeozoic and Mesozoic tectonism of the western Barents Shelf

Alvar Braathen, Harmon D. Maher, Tora E. Haabet, Stein Erik Kristensen, Bjørn Ove Tørudbakken, David Worsley

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

The late Proterozoic to Ordovician rocks on Bjornoya, located on the western Barents Shelf, experienced significant contractional deformation during the Caledonian orogeny, contrary to some descriptions. Major thrust zones bound the various pre-Devonian basement units of the island, and the Upper Riphean-Vendian to Middle Ordovician rocks are stacked in a WNW-verging thrust pile. In detail, mesoscopic structures, such as ductile shear folds and fabrics, brittle faults with appropriate slip-lines, and stacked units, support a contractional nature of the deformation. An unconformity with overlying Upper Devonian sandstones truncates all the major basement thrusts, thereby indicating a Caledonian age for the major deformation of the basement units. Later, Palaeozoic normal faults dissect the basement units and upper Devonian to mid-Carboniferous cover rocks. During this faulting episode, all units were also folded into a monocline. A strong similarity in orientation of the basement- and cover-related fault populations indicates that these extensional faults were controlled by the Caledonian structural grain. The Palaeozoic normal faults have also utilized the Caledonian contractional fabric, supporting basement control on the Palaeozoic extension in the area. Using Bjornoya as a guide, we discuss the importance of the Caledonian basement grain for Palaeozoic and Mesozoic extension of the western Barents Shelf.

Original languageEnglish (US)
Pages (from-to)57-68
Number of pages12
JournalNorsk Geologisk Tidsskrift
Volume79
Issue number1
DOIs
StatePublished - Jan 1 1999

Fingerprint

Caledonian orogeny
Paleozoic
thrust
normal fault
Ordovician
rock
monocline
Riphean
Vendian
unconformity
Proterozoic
faulting
pile
sandstone
fold
fabric

ASJC Scopus subject areas

  • Geology

Cite this

Caledonian thrusting on Bjornoya : Implications for Palaeozoic and Mesozoic tectonism of the western Barents Shelf. / Braathen, Alvar; Maher, Harmon D.; Haabet, Tora E.; Kristensen, Stein Erik; Tørudbakken, Bjørn Ove; Worsley, David.

In: Norsk Geologisk Tidsskrift, Vol. 79, No. 1, 01.01.1999, p. 57-68.

Research output: Contribution to journalArticle

Braathen, Alvar ; Maher, Harmon D. ; Haabet, Tora E. ; Kristensen, Stein Erik ; Tørudbakken, Bjørn Ove ; Worsley, David. / Caledonian thrusting on Bjornoya : Implications for Palaeozoic and Mesozoic tectonism of the western Barents Shelf. In: Norsk Geologisk Tidsskrift. 1999 ; Vol. 79, No. 1. pp. 57-68.
@article{9f5b511133184975bfab4598361f3317,
title = "Caledonian thrusting on Bjornoya: Implications for Palaeozoic and Mesozoic tectonism of the western Barents Shelf",
abstract = "The late Proterozoic to Ordovician rocks on Bjornoya, located on the western Barents Shelf, experienced significant contractional deformation during the Caledonian orogeny, contrary to some descriptions. Major thrust zones bound the various pre-Devonian basement units of the island, and the Upper Riphean-Vendian to Middle Ordovician rocks are stacked in a WNW-verging thrust pile. In detail, mesoscopic structures, such as ductile shear folds and fabrics, brittle faults with appropriate slip-lines, and stacked units, support a contractional nature of the deformation. An unconformity with overlying Upper Devonian sandstones truncates all the major basement thrusts, thereby indicating a Caledonian age for the major deformation of the basement units. Later, Palaeozoic normal faults dissect the basement units and upper Devonian to mid-Carboniferous cover rocks. During this faulting episode, all units were also folded into a monocline. A strong similarity in orientation of the basement- and cover-related fault populations indicates that these extensional faults were controlled by the Caledonian structural grain. The Palaeozoic normal faults have also utilized the Caledonian contractional fabric, supporting basement control on the Palaeozoic extension in the area. Using Bjornoya as a guide, we discuss the importance of the Caledonian basement grain for Palaeozoic and Mesozoic extension of the western Barents Shelf.",
author = "Alvar Braathen and Maher, {Harmon D.} and Haabet, {Tora E.} and Kristensen, {Stein Erik} and T{\o}rudbakken, {Bj{\o}rn Ove} and David Worsley",
year = "1999",
month = "1",
day = "1",
doi = "10.1080/002919699433915",
language = "English (US)",
volume = "79",
pages = "57--68",
journal = "Norsk Geologisk Tiddsskrift",
issn = "0029-196X",
publisher = "Geological Society of Norway",
number = "1",

}

TY - JOUR

T1 - Caledonian thrusting on Bjornoya

T2 - Implications for Palaeozoic and Mesozoic tectonism of the western Barents Shelf

AU - Braathen, Alvar

AU - Maher, Harmon D.

AU - Haabet, Tora E.

AU - Kristensen, Stein Erik

AU - Tørudbakken, Bjørn Ove

AU - Worsley, David

PY - 1999/1/1

Y1 - 1999/1/1

N2 - The late Proterozoic to Ordovician rocks on Bjornoya, located on the western Barents Shelf, experienced significant contractional deformation during the Caledonian orogeny, contrary to some descriptions. Major thrust zones bound the various pre-Devonian basement units of the island, and the Upper Riphean-Vendian to Middle Ordovician rocks are stacked in a WNW-verging thrust pile. In detail, mesoscopic structures, such as ductile shear folds and fabrics, brittle faults with appropriate slip-lines, and stacked units, support a contractional nature of the deformation. An unconformity with overlying Upper Devonian sandstones truncates all the major basement thrusts, thereby indicating a Caledonian age for the major deformation of the basement units. Later, Palaeozoic normal faults dissect the basement units and upper Devonian to mid-Carboniferous cover rocks. During this faulting episode, all units were also folded into a monocline. A strong similarity in orientation of the basement- and cover-related fault populations indicates that these extensional faults were controlled by the Caledonian structural grain. The Palaeozoic normal faults have also utilized the Caledonian contractional fabric, supporting basement control on the Palaeozoic extension in the area. Using Bjornoya as a guide, we discuss the importance of the Caledonian basement grain for Palaeozoic and Mesozoic extension of the western Barents Shelf.

AB - The late Proterozoic to Ordovician rocks on Bjornoya, located on the western Barents Shelf, experienced significant contractional deformation during the Caledonian orogeny, contrary to some descriptions. Major thrust zones bound the various pre-Devonian basement units of the island, and the Upper Riphean-Vendian to Middle Ordovician rocks are stacked in a WNW-verging thrust pile. In detail, mesoscopic structures, such as ductile shear folds and fabrics, brittle faults with appropriate slip-lines, and stacked units, support a contractional nature of the deformation. An unconformity with overlying Upper Devonian sandstones truncates all the major basement thrusts, thereby indicating a Caledonian age for the major deformation of the basement units. Later, Palaeozoic normal faults dissect the basement units and upper Devonian to mid-Carboniferous cover rocks. During this faulting episode, all units were also folded into a monocline. A strong similarity in orientation of the basement- and cover-related fault populations indicates that these extensional faults were controlled by the Caledonian structural grain. The Palaeozoic normal faults have also utilized the Caledonian contractional fabric, supporting basement control on the Palaeozoic extension in the area. Using Bjornoya as a guide, we discuss the importance of the Caledonian basement grain for Palaeozoic and Mesozoic extension of the western Barents Shelf.

UR - http://www.scopus.com/inward/record.url?scp=0033039751&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0033039751&partnerID=8YFLogxK

U2 - 10.1080/002919699433915

DO - 10.1080/002919699433915

M3 - Article

AN - SCOPUS:0033039751

VL - 79

SP - 57

EP - 68

JO - Norsk Geologisk Tiddsskrift

JF - Norsk Geologisk Tiddsskrift

SN - 0029-196X

IS - 1

ER -