Field Guide 26

By A.H.N. Rice, Marc B. Edwards, and T.A. Hansen Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/3738115/9780813756264_frontmatter.pdf by guest on 28 September 2021 Neoproterozoic Glacial and Associated Facies in the Tanafjord- Area, , North

by

A.H.N. Rice Department of Geodynamics and Sedimentology University of Vienna Althanstrasse 14 1090 Vienna Austria

Marc B. Edwards 3420 Yoakum Blvd Houston, Texas 77006 USA

T.A. Hansen Talisman Energy Norge AS Verven 4 PO Box 649 Stavanger Norway

Field Guide 26 3300 Penrose Place, P.O. Box 9140 Boulder, Colorado 80301-9140, USA 2012

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All photos courtesy of Hugh Rice except for Figures 44B and 65B.

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Library of Congress Cataloging-in-Publication Data

Rice, A. H. N. (A. Hugh N.) Neoproterozoic glacial and associated facies in the Tanafjord-Varangerfjord area, Finnmark, north Norway / by A.H.N. Rice, Marc B. Edwards, T.A. Hansen. p. cm. Includes bibliographical references. ISBN 978-0-8137-0026-7 (pbk.) 1. Facies (Geology)—Norway—Tanafjorden. 2. Facies (Geology)—Varanger (Norway and ) 3. Geology—Norway—Finnmark fylke. 4. Geology, Stratigraphic—Proterozoic. I. Edwards, Marc B. II. Hansen, T. A. (Tor Arne) III. Title. QE281.R53 2012 554.84′6—dc23

2011053489

Front cover: Early evening view from Geaidnonjoasèohkat, northeastward to the peninsula (Álddarbákti) between Máldovuotna in the west and Vestertana in the east and thence across Tanafjord to Lille Molvika, on Varangerhalvøya, in the east (see Figs. 1 and 3 for direction of view). The hills on Varangerhalvøya are mostly quartzitic sandstones of the pre–Smalfjord Formation (≡Marinoan Glaciation) Tanafjord Group. The rounded steep-sided hills on the photo’s west side are of the Digermul Group, reaching from the Cambrian up to the Tremadocian. The low-lying rugged areas between, on the west side of Tanafjord and around Vestertana, are from the Vestertana Group (Ediacaran-Cambrian), here mostly of the Nyborg Formation, Mortensnes Formation (≡Gaskiers Glaciation), and younger rocks. The picture was taken standing on the Thin Sub-Member of the Middle Member of the Mortensnes Formation. The Thick Sub-Member forms the long buff-colored outcrop (Hárjas) beyond Louvdajavrit (the large lakes) on the southeast side of Máldovuotna. The ridges in the foreground, around and above the small lake, reflect the periodic mesoscale east-vergent folding in Member B of the Nyborg Formation. 10 9 8 7 6 5 4 3 2 1

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Abstract ...... 1

Introduction ...... 2

Logistics ...... 2 Excursion timing ...... 2 Travel arrangements ...... 2 Accommodations ...... 2 Field logistics ...... 3 Maps and literature ...... 3

Geological Introduction ...... 4 Stratigraphy, sedimentology, and paleontology ...... 6 Structure and metamorphism ...... 8 Isotopic age constraints ...... 8 Magmatic history ...... 9 Paleolatitude and paleogeography ...... 9 Glacigenic deposits and associated strata ...... 9 Smalfjord Formation (≡ Marinoan Glaciation; late Cryogenian)...... 10 Nyborg Formation (interglacial succession) ...... 11 Mortensnes Formation (≡ Gaskiers Glaciation) ...... 12 Innerelv Member (postglacial) ...... 12 Facies and paleogeographic interpretation ...... 12 Stable isotopes and Neoproterozoic correlations ...... 14

Natural History and Cultural Background ...... 15

Excursion Route and Road Log ...... 19 Day 1. Lower Smalfjord Formation in South Varangerfjord and West , Varanger paleovalley (I) ...... 19 Introduction ...... 19 Stop 1.1: Lattanjar’ga Peninsula ...... 19 Stop 1.2: Gåppebalta and Sirdagåp’pi, S. Karlebotn ...... 21 Stop 1.3: Mar’kan (Karlebotn village) ...... 23 Stop 1.4: Karlebotn School ...... 24 Day 2. Lower Smalfjord Formation at Oaibaččanjar’ga and Selešnjar’ga, Varanger paleovalley (II) ...... 24 Introduction ...... 24 Stop 2.1: Vesterelv ...... 25 Stop 2.2: Oaibaččannjar’ga (Bigganjar’ga, Cape Headache) ...... 25 Stop 2.3: Larajœg’gi and unnamed hill ...... 30

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Day 3. Lower Smalfjord Formation on Skjåholmen and Vieranjar’ga, Varanger paleovalley (III) ...... 31 Introduction ...... 31 Stop 3.1: Southeast coast of Skjåholmen viewed from the boat ...... 31 Stop 3.2: Skjåholmen eastern end ...... 33 Stop 3.3: View of NE corner of Vieranjar’ga peninsula ...... 34 Stop 3.4: Vieranjar’ga peninsula ...... 34 Day 4. Lower Smalfjord Formation and cap dolostones along N. Varangerfjord and Leirpollen, Varanger paleovalley (IV) ...... 40 Introduction ...... 40 Stop 4.1: Handelsneset ...... 44 Stop 4.2: Hammarnes Quarry ...... 46 Stop 4.3: Gis’kananjåkka (east of ) ...... 47 Stop 4.4: View to Ruok’sadas ...... 49 Stop 4.5: Leirpollen ...... 49 Day 5. Glacigenic rocks in the South Tanafjord-Vestertana area ...... 51 Introduction ...... 51 Stop 5.1: Šœresgied’djav’ri ...... 51 Stop 5.2: Auskarnes ...... 52 Stop 5.3: Torhop ...... 52 Stop 5.4: SW Duoivejeakkečohkat (east side Vestertana) ...... 52 Stop 5.5: Šuoššjåkka ...... 54 Stop 5.6: East of Poas’tagurra ...... 54 Stop 5.7: Geaidnonjoasèohkat ...... 54 Day 6. Upper Smalfjord Formation on Gæssenjar’ga ...... 55 Introduction ...... 55 Stop 6.1: View of Gæssenjar’ga from the road corner west of Torhop ...... 55 Stop 6.2: Gæssenjar’ga ...... 57 Day 7. Mortensnes Formation in the Las’sasuolo-Låk’sunjåkka coastal profile, West Tanafjord ...... 63 Introduction ...... 63 Stop 7.1: Las’sasuolo-Låk’sunjåkka (Stappugied’di) coastal profile ...... 63 Day 8. Associated Neoproterozoic strata along the Varanger Coast (Vadsø to Hamningberg) . . . . 76 Introduction ...... 76 Stop 8.1: Sjåbuselva, east of Kiby ...... 76 Stop 8.2: Ekkerøya bird colony ...... 77 Stop 8.3: West of Komagnes ...... 78 Stop 8.4: SSW of Hestmannes ...... 79 Stop 8.5: Persfjord ...... 79 Stop 8.6: Storflognakken ...... 79

Acknowledgments ...... 80

References Cited ...... 80

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