Masterarbeit
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Masterarbeit Titel der Masterarbeit Landscape evolution north of the Sonnblick (Salzburg) during the Alpine Lateglacial verfasst von Mathias Bichler B.Sc. gemeinsam mit Martin Reindl B.Sc. angestrebter akademischer Grad Master of Science (M.Sc.) Wien, 2013 Studienkennzahl lt. Studienblatt:A 066 815 Studienrichtung lt. Studienblatt:Masterstudium Erdwissenschaften Betreut von:Hermann Häusler, Ao. Univ. Prof. Dr. Contents 1. Preface [Reindl] 7 2. The Study Area [Reindl/Bichler] 9 2.1. Overview [Reindl] ............................... 9 2.2. Lateglacial Stratigraphy and Terminology [Bichler] ............ 12 2.3. Previous Research [Bichler] .......................... 18 2.4. Morphological and Geological Setting [Bichler] ............... 23 2.4.1. The Tauern Window ......................... 23 2.4.2. Kolm-Saigurn ............................. 23 2.4.2.1. Bedrock Geology ...................... 23 2.4.2.2. Morphology ......................... 26 2.5. Aims and Goals [Reindl] ........................... 29 3. Methods [Reindl/Bichler] 31 3.1. Mapping [Bichler] ............................... 31 3.1.1. Geological and Geomorphological Mapping ............. 31 3.1.2. Digital Elevation Model ....................... 32 3.1.3. Geographic Information System - GIS ................ 32 3.1.4. Lithofacies Description ........................ 33 3.2. Dating Methods [Reindl] ........................... 35 3.2.1. Surface Exposure Dating ....................... 35 3.2.2. Radiocarbon Dating ......................... 38 3.2.3. Errors and Limitations ........................ 39 4. Field Evidence [Reindl/Bichler] 41 4.1. Hüttwinklache [Reindl] ............................ 41 4.2. Durchgangwald [Reindl] ........................... 45 4.2.1. Description .............................. 45 4.2.2. Interpretation ............................. 47 3 Contents 4.3. Filzenalm [Reindl] ............................... 49 4.3.1. Description .............................. 49 4.3.2. Interpretation ............................. 50 4.4. Kolm-Saigurn [Bichler] ............................ 51 4.4.1. Description .............................. 51 4.4.2. Interpretation ............................. 52 4.5. Grieswiesalm [Reindl] ............................. 53 4.5.1. Description .............................. 53 4.5.2. Interpretation ............................. 55 4.6. Lenzanger and Gersteben [Reindl] ...................... 55 4.6.1. Description .............................. 55 4.6.2. Interpretation ............................. 56 4.7. Bodenhaus [Reindl] .............................. 58 4.7.1. Description .............................. 58 4.7.2. Interpretation ............................. 59 4.8. Knappenhaus [Bichler] ............................ 61 4.8.1. Description .............................. 61 4.8.2. Interpretation ............................. 62 4.9. Grieswiestauern [Bichler] ........................... 62 4.9.1. Description .............................. 62 4.9.2. Interpretation ............................. 63 4.10. Goldbergkees [Bichler] ............................ 63 4.10.1. Description .............................. 63 4.10.2. Interpretation ............................. 63 4.11. Forefront Goldbergkees [Bichler] ....................... 64 4.11.1. Description .............................. 64 4.11.2. Interpretation ............................. 65 4.12. Pilatuskees [Bichler] .............................. 68 4.12.1. Description .............................. 68 4.12.2. Interpretation ............................. 69 4.13. Forefront Pilatuskees [Bichler] ........................ 69 4.13.1. Description .............................. 69 4.13.2. Interpretation ............................. 69 4.14. Melcherböden [Bichler] ............................ 70 4.14.1. Description .............................. 70 4 Contents 4.14.2. Interpretation ............................. 70 4.15. Durchgangriegel [Bichler] ........................... 70 4.15.1. Description .............................. 70 4.15.2. Interpretation ............................. 72 4.16. Summary [Bichler] .............................. 73 4.16.1. Durchgangwald Landslide ...................... 74 4.16.2. Kolm-Saigurn Glacier System .................... 74 4.16.3. The Quartzite Landslide ....................... 75 5. Dating [Reindl/Bichler] 77 5.1. The Durchgangwald landslide [Reindl] ................... 77 5.2. The Kolm-Saigurn Glacier System [Bichler] ................. 81 5.2.1. Glacial Advance and Maximum Extent ............... 81 5.2.2. Glacial Retreat ............................ 81 5.2.2.1. Kolm-Saigurn basin .................... 82 5.2.2.2. Grieswiestauern and Melcherböden ............ 82 5.3. The Quartzite landslide [Reindl] ....................... 84 6. Glacier Dynamics [Reindl/Bichler] 87 6.1. The Kolm-Saigurn Confluence Situation [Bichler] ............. 87 6.2. Equilibrium Line Altitudes [Reindl] ..................... 92 6.2.1. Methods ................................ 93 6.2.1.1. Maximum Elevation of Lateral Moraines ......... 93 6.2.1.2. Toe-to-Headwall Altitude Ratio .............. 95 6.2.1.3. Area × Altitude ...................... 97 6.2.1.4. Accumulation Area Ratio ................. 98 6.2.1.5. Area × Altitude Balance Ratio .............. 99 6.2.2. Comparison ..............................100 6.2.2.1. ELA synthesis .......................100 6.2.2.2. The Younger Dryas local climate .............101 6.3. Ice thickness modelling [Reindl] .......................104 7. Synthesis [Reindl/Bichler] 109 7.1. Landscape Evolution [Reindl] ........................109 7.2. Stratigraphic Correlation [Bichler] ......................114 8. Discussion and Conclusion [Reindl/Bichler] 119 5 Contents 9. Acknowledgments [Reindl/Bichler] 123 10.Abstracts [Reindl/Bichler] 125 10.1. Abstract ....................................125 10.2. Zusammenfassung ...............................126 Appendix A. Mathematica Notebooks [Reindl] 129 AAR ELA calculation ...............................129 Topographic shielding ...............................130 Appendix B. AA and AABR Tables [Reindl] 133 Appendix C. Geologic Map [Bichler] 141 Curriculum Vitae 161 Martin Reindl ....................................161 Mathias Bichler ...................................163 6 1. Preface [Reindl] The Hoher Sonnblick or Rauriser Sonnblick in the Hohe Tauern alpine range in the Austrian province of Salzburg has a long history of scientific research. The summit area houses the highest meteorological Observatory in Austria (3106m asl), operated by the Zentralanstalt für Meteorologie und Geodynamik (ZAMG). This observatory was opened in 1886 and since then has an uninterrupted record of climatic data in an alpine environment. Every year 40 to 50 projects work on or around the alpine area of the Sonnblick and the glacier which plays such a big role in the valley head of the Hüttwinkl valley, the Goldbergkees. These projects center on the topics of environmental research like atmospherics chemistry, atmospheric physics, precipitation chemistry, avalanche re- search, climate research, and glacial research, but rarely geomorphology and Quaternary studies. In 2010, Ao. Univ. Prof. Dr. Hermann Häusler from the University of Vienna and Dr. Wolfgang Schöner of the ZAMG planned to research and date the diverse landforms (moraine ridges and landslides) in the area of Kolm-Saigurn, the head of the Hüttwinkl valley. With this spirit in mind, a field trip from the University of Vienna, under the supervision of Ao. Univ. Prof. Dr. Hermann Häusler and Dr. Jürgen Reitner of the Geological Survey of Austria (Geologische Bundesanstalt - GBA) was undertaken to explore the unique geomorphologic features. It was during this field trip, where the idea was born to investigate the full chronology of events during the Lateglacial ice decay. The GBA showed great interest in mapping the area part of the recently mapped Blatt 154, Rauris, being part of the Austrian geological map. This initial idea was then formulated and transformed into a project, where this document marks the final report. The goal was to clarify the time-stratigraphic position of the multiple identified glacial-deposits (moraines, boulders). During the beginning stages of this project it became clear that not only the sediment evidence from earlier glaciers played a vital role in the history of this specific valley head, but also numerous landslides left their traces. As the field work revealed temporal unique relationships of cross-cutting landscape elements, a solid relative chronology of 7 1. Preface [Reindl] the processes was given. It was worth trying to establish an absolute chronology for all major events with the help of 10Be exposure dating from boulders and bedrock and with the help of 14C dating of base-layers from peat-bogs. This document now represents the synthesis of our work, where we try to shed some light on the surface dynamics and document the special geomorphologic and Quaternary features and settings that make up the area north of the Hoher Sonnblick in the head of the Hüttwinkl valley. Our decision to write one master thesis was based on numerous reasons. While the initial extent of the area might have justified a single thesis, the amount of work in- volved with sampling and preparation, especially the 10Be method, was just too much to guarantee a successful outcome. During the course of our work it became apparent that the synergy when working as a team on these samples was very high. In addition, the relationship of the features high up on the mountain in the forefront of