Applying GIS Analysis to Archaeological Research in Canada T A L K B Y D R. K I S H A S U P E R N A N T P R E S E N T E D A T G E O A L B E R T A 2 0 1 3 S E P T E M B E R 2 3, 2 0 1 3
Overview Review of the application of GIS/mapping to archaeology Discussion of the types of GIS analyses we use Case Studies Prince Rupert Harbour, BC Lower Fraser River Canyon, BC Summary and Future Directions 2
We ve always mapped
Technology changes mapping practice Accessibility of GIS software Ability to perform analysis at large scales with many data points (i.e. LiDAR) Increasing ability to share data via cloud storage and online maps Advances in 3D modeling Advances in mapping technology allows for quick collection of high-quality data
Visualization Role of maps in archaeology Allows us new ways of perceiving and presenting archaeological data Excellent for dissemination of results 5 NOT necessarily connected to new ways of thinking about the archaeological record
Research Role of maps in archaeology Asking new spatial questions (or applying old questions) to archaeological data Use maps for interpretation, not just representation Can use them to streamline and test previous forms of analysis i.e. settlement density Can also use them to expand or invent new forms of analysis i.e. viewshed Combine multiple forms of archaeological and nonarchaeological data for more robust analysis 6
Visualization Research 7
Dissemination New methods have transformed how we disseminate archaeological knowledge: http://en.ancientmaize.com/maps http://www.thebanmappingproject.com/ http://www.youtube.com/watch?v=gryv34hvruw
Some typical spatial analyses Predictive Modeling Common in NA in a management context High and low potential for sites can be generated based on a series of factors Visibility/Viewshed Can sites see each other? How far can sites see? What monuments can be seen from where? Site Catchment analysis Proximity of locations to other features Cost surface analysis Routes and barriers Trend surface and spatial allocation 9
Types of Research Questions: Vectors Clustering or relationships between variables Density Distribution Intersection Overlap Patterning 10 Questions related to discrete variables tend to rely on vector data
Example of Vector Analysis 11
Proximity to Resources 12
Types of Research Questions: Rasters Movement across the landscape How do people move through the world? Visibility What can be seen from different points on the landscape? Predictive modeling Where are archaeological sites most likely to be located? 13
Examples of analysis: Rasters Digital Elevation Models Provide base data for many types of analysis Can calculate pseudo-3d models of landscapes 14 Original DEM Slope Hillshade
Data required: Base DEM data Predictive Model Any other relevant land feature information (vegetation, land use, soil information, geology, hydrology) More = better model Raster or vector formats can work Point features for which information can be generated Archaeological sites 15
Analyses required: Predictive Model Large variety depending on the number of variables: Slope, aspect Distances to streams Soil productivity Viewshed Statistical Analysis Univariate statistical methods (chi-squared, K-S) Logistic regression analysis Computation time: High for desktop resources 16
Maps as archaeological data Digital maps are robust datasets 3D with potential to be 4D Use of GIS software for complex mathematical analysis of landscapes Spatial data can be analysed at several scales: Intersite, including regional analysis Environmental variables Social variables Intrasite, including excavation unit analysis Artifact distribution Faunal remains distribution 17
Settlement Patterns 18
Defensibility 19
Visibility 20
Site change through time 3D modeling Isovists Intrasite: possibilities Measuring visibility in 3 dimensions Conceptual surface mapping Alternative topographies 21 Micro-topographic analysis
Examples from Prince Rupert Landscape analysis Modeling changing sea levels and resulting landscapes Querying temporal and spatial changes in settlement patterns Site analysis 22 Landscape modification using shell Conceptual maps of site perception
Landscape Change 23
Movement: Travel Time 24
Tracing Lost House Depressions 25
Shell-scaping? Landscape Modification 26
Examples from Lower Fraser River Canyon 27
Archaeological Visibility 28
Intervisibility 29 Site DjRi-14 DjRi-21 DjRi-13 DjRi- 62 DjRi- 3/5 DjRi- 2(S) DjRi- 2(N) DjRi- 46 DjRi-14 - Yes No No No No No No DjRi-21 Yes - Yes Yes No No No No DjRi-13 No Yes - Yes Yes No No No DjRi- 62 DjRi3/ 5 DjRi- 2(S) DjRi- 2(N) DjRi- 46 No No Yes - Yes No No No No No No Yes - Yes Yes No No No No No Yes - Yes No No No No No Yes Yes - No No No No No Yes No No -
Social Identity and Spatial Organization 30
Conclusions 31 Rock features locations where identities can be mediated and managed at many scales Internally and externally Symbolic markers of identity and ownership Located at significant points on the landscape Used to enhance defensibility on the landscape
Summary Mapping has always be a part of archaeology Advances in technology and GIS have provided robust spatial datasets for analysis Possibilities for GIS analysis of spatial data are immense Potential to answer old questions and inspire new ones Always looking to find new ways to use and analyse data 32
Thank You 33