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Table of Content
1. Introduction ... 9
2. Geological Background ... 12
2.1 Late Proterozoic metasediments of the North Atlantic Caledonides ... 12
2.1.1 Eastern Laurentian margin ... 13
2.1.2 Western and northern Baltic margin ... 17
2.1.3 Arctic Terranes ... 18
2.1.3.1 The Pearya terrane ... 18
2.1.3.2 The Arctic Alaska Chukotka Terrane ... 19
2.1.3.3 Other Arctic Terranes ... 19
2.1.4 Svalbard ... 20
2.1.4.1 The Eastern Basement Province ... 20
2.1.4.2 The Northwestern Basement Province ... 21
2.1.4.3 Southwestern Basement Province ... 22
3. Methods ... 26
3.1 Zircon separation ... 26
3.2 U-Pb zircon dating ... 26
3.3 Data filtering and analysis ... 26
3.4 Mineral chemistry and element maps EMPA ... 27
3.5 Th-U-total Pb dating of monazite... 27
4. Chapter I: Defining tectonic boundaries using detrital zircon geochronology – Southwestern Caledonian Basement Province of Svalbard ... 29
4.1 Introduction ... 29
4.2 U-Pb detrital zircon geochronology ... 29
4.2.1 Southern Wedel Jarlsberg Land and Sorkapp Land ... 29
4.2.1.1 U-Pb detrital zircon geochronology of Eimfjellet Complex ... 31
4.2.1.2 U-Pb detrital zircon geochronology of Isbjørnhamna Group ... 32
4.2.1.3 U-Pb detrital zircon geochronology of Unit 35 of Sørkapp Land ... 32
4.2.1.4 U-Pb detrital zircon geochronology of the Deillega Group and the Sofiebogen Group ... 33
4.3 Discussion ... 34
4.3.1 Age groups and trends ... 34
4.3.2 The Gullichsenfjellet Formation ... 35
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4.3.4 Northeastern subprovince of WJL ... 39
4.3.5 Defining tectonic boundaries using detrital zircon age signatures ... 40
4.4 Conclusions ... 41
5. Chapter II: Lithotectonic Group 2 metasediments of the SBP ... 43
5.1 Introduction ... 43
5.2 Sample description ... 43
5.2.1 Berzeliuseggene – Martinfjella area ... 43
5.2.2 Central Oscar II Land ... 45
5.3 U-Pb detrital zircon geochronology of LTG2 metasediments ... 46
5.3.1 Deilegga Group (?) ... 46
5.3.2 Müllerneset Formation ... 47
5.3.3 St. Jonsfjorden Group ... 47
5.4 Discussion ... 49
5.4.1 Age groups and trends ... 49
5.4.2 Regional implications ... 50
5.4.3 The LTG2 rocks of Svalbard ... 52
5.4.4 Implications for North Atlantic region ... 54
5.5 Conclusions ... 58
6. Chapter III: Metasedimentary rocks of Lithotectonic Group 3 ... 59
6.1 Introduction ... 59
6.2 Sample description ... 59
6.3 U-Pb detrital zircon geochronology ... 61
6.3.1 The Deilegga Group ... 61
6.3.2 The Nordbukta Group ... 62
6.4 Discussion ... 62
6.4.1 The LTG2 metasediments of the Svalbard and their relations to the Pearya Terrane ... 62
6.4.2 Implications for the North Atlantic region ... 65
6.5 Conclusions ... 67
7. Chapter IV: Early Devonian sinistral transpression of the Caledonian Basement in Oscar II Land ... 69
7.1 Introduction ... 69
7.2 Previous research in the Müllerneset Formation ... 69
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7.3.1 Field observations ... 70
7.3.1.1 Western Svartfjellstranda ... 72
7.3.1.2 Eastern Svartfjellstranda ... 76
7.3.1.3 The Chaotic Zone ... 76
7.3.2 Petrography and mineral chemistry ... 79
7.3.3 Monazite chemistry and geochronology ... 85
7.4 Discussion ... 87
7.4.1 Metamorphic evolution ... 87
7.4.2 Tectonic implications ... 90
7.4.2.1 Structural framework of the Müllerneset Formation ... 90
7.4.2.2 Relation to remaining Oscar II Land Caledonian Basement ... 91
7.4.2.3 Implications for structural development of the Southwestern Basement Province ... 93
7.5 Conclusions ... 94
8. Concluding remarks ... 96
8.1 Proterozoic metasediments of Svalbard and their affinities ... 96
8.1.1 Inhomogeneity of the Proterozoic provenance in the SBP ... 96
8.1.2 Relationship of the SBP with Laurentia and Pearya Terrane ... 96
8.2 Late Silurian – Early Devonian assembly of Svalbard ... 98
9. References ... 101
10. List of figures ... 118
11. List of tables ... 125
Appendix A: U-Pb geochronological data for chapter I. ... 126
Appendix B: U-Pb geochronological data for chapter II. ... 135
Appendix C: U-Pb geochronological data for chapter III. ... 151
Appendix D. Representative chemical analysis of REE minerals in wt. % and recalculated to a.p.f.u. (Chapter IV). ... 165
Appendix E. Chemical analyses of monazite recalculated to a.p.f.u. (Chapter IV). ... 166
