Department of Geosciences, Geography University of Fribourg, Switzerland Geospatial modelling of the glacial archaeological potential in the Pennine Alps THESIS Presented to the Faculty of Science of the University of Fribourg (Switzerland) in consideration for the award of the academic grade of Doctor rerum naturalium by Stephanie R. Rogers from Canada Thesis No: 1858 UNIprint 2014 CONTENTS Summary ...................................................................................................................................................................... 5 Résumé ......................................................................................................................................................................... 6 List of Figures .............................................................................................................................................................. 7 List of Tables ................................................................................................................................................................ 9 List of Abbreviations ................................................................................................................................................ 11 1 General Introduction ............................................................................................................................................. 13 1.1 Motivation ........................................................................................................................................................ 13 1.2 Objectives ......................................................................................................................................................... 17 1.3 Structure of the thesis ..................................................................................................................................... 18 2 The Pennine Alps ................................................................................................................................................... 20 2.1 Glaciological context ....................................................................................................................................... 21 2.2 Production of a geospatial database for the Pennine Alps ........................................................................ 23 3 Geospatial Analysis & Glacial Archaeology ....................................................................................................... 27 3.1 Paper I: An overview of selected GIS methods available for use in glacial archaeology ...................... 29 4 Integrative Approach ............................................................................................................................................. 47 4.1 Paper II: Least cost path analysis for predicting glacial archaeological site potential in central Europe ................................................................................................................................................................................. 49 4.2 Paper III: Least cost path analysis for predicting archaeological potential: scale and parameter investigations ......................................................................................................................................................... 72 4.3 Paper IV: Combining glaciological and archaeological methods for gauging glacial archaeological potential .................................................................................................................................................................. 89 5 General Discussion ............................................................................................................................................... 118 5.1 Summary of results ....................................................................................................................................... 118 5.2 The use of geospatial technologies.............................................................................................................. 121 5.3 Future outlook ............................................................................................................................................... 123 6 Bibliography.......................................................................................................................................................... 125 Acknowledgements ................................................................................................................................................ 130 Curriculum vitae ..................................................................................................................................................... 131 SUMMARY Humans have a longstanding relationship with frozen environments. Although this relationship is not fully understood, humans are known to have frequented frozen regions for thousands of years to obtain resources or to move between locations. Recent changes in climate have increased melting of glaciers, ice patches, and permafrost at high latitudes and altitudes. In some regions, thawing of these environments has led to the accidental discovery of archaeological remains or artefacts. As a result, archaeologists have shifted their research to frozen areas in an attempt to collect and preserve unique glacial archaeological findings. The Pennine Alps, located between the canton of Valais in Switzerland and the provinces of Aosta and Piedmont in Italy, is a region of glacial archaeological interest due to its vast glaciated terrain and rich cultural history dating back to the Mesolithic (12,000 – 9,000 years BP). The high altitude passes located on the border between Switzerland and Italy have been used as trade, commerce, and migration routes for thousands of years. The melting of glaciers in this region is freeing-up archaeological remains on passes or surrounding areas that support their prehistoric and historic use. Due to the organic composition of many potential remains (e.g. wood, clothing), there is an urgent need to collect these items before they are destroyed. However, the high altitudes at which potential sites are located are not conducive to regular systematic archaeological prospection due to their remoteness and inaccessibility. Geospatial analyses, incorporating information from geographical, historical, and archaeological sources, offer a unique opportunity to determine glacial archaeological potential. In this thesis, geospatial analyses using Geographic Information Systems (GIS) and glaciological methods were employed to determine areas of highest glaciological potential in the Pennine Alps to help locate, collect, and preserve unique glacial archaeological objects in partnership with archaeologists and historians as part of a multidisciplinary project funded by the Swiss National Science Foundation (SNSF). Using various geospatial methods, including least cost path and locational analyses and glaciological modelling, 31 high altitude passes of glacial archaeological interest and potential were identified in the Pennine Alps. A Bronze Age artefact was discovered after the archaeological prospection at one of these sites which was previously unknown to archaeologists and historians. This demonstrates that geospatial analyses can be used to focus archaeological prospection by narrowing down large, remote, study regions to sites of a few square kilometers to support decisions about where to conduct current and future archaeological prospection. Future efforts should continue to use geospatial analyses to focus on the archaeology of frozen regions to identify areas of potential in order to avoid losing unique information about past cultures and climates. 5 RÉSUMÉ Les humains fréquentent les environnement froids et englacés depuis des milliers d'années, comme passage permettant de relier deux régions ou dans le but d’en exploiter les ressources. Dans certaines zones de haute montagne et situées sous les hautes latitudes, la fonte et le retrait des glaciers, des névés et du pergélisol, liés à des changements climatiques récents, a ainsi permis la découverte, souvent accidentelle, d’artéfacts et de restes archéologiques. Ces découvertes ont éveillé l’intérêt des archéologues pour ces régions englacées et ont ainsi contribué au développement de l’archéologie glaciaire. Le but des recherches dans ce domaine étant de collecter et de conserver ces objets uniques, fraîchement libérés des glaces, avant qu’ils ne disparaissent pour toujours. Les Alpes pennines désignent la région comprise entre le canton du Valais en Suisse et les provinces d'Aoste et du Piémont en Italie. En raison de l’étendue des masses glaciaires et de sa longue histoire culturelle qui a débuté au mésolithique (12'000-9'000 années BP), cette région représente un grand intérêt pour l'archéologie glaciaire. Les cols de hautes altitudes situés à la frontière entre la Suisse et l'Italie ont servi de routes commerciales, ainsi que de voie de migration depuis des milliers d'années. Des objets archéologiques, mis à jour par le retrait glaciaire sur les cols et dans leurs environs, apportent des indices quant à leur utilisation historique et préhistorique. Or, ces artéfacts, étant fréquemment de composition organique (comme le bois ou les pièces de vêtements), se décomposent rapidement au contact de l'air. Il y a par conséquent une urgence de les collecter avant qu'ils ne se dégradent.