⚓Archaeology of the Age of Exploration Unit 10 – Archaeological Methods in History

Key Concepts and Terminology

• Stratigraphy involves the study of layered deposits to establish relative chronology of a site
  • Law of Superposition states that in an undisturbed sequence, younger layers are deposited on top of older layers
• Typology classifies artifacts based on shared physical characteristics to establish chronologies and cultural affiliations
• Absolute dating methods provide specific dates or date ranges for artifacts and sites
  • Radiocarbon dating measures the decay of carbon-14 in organic materials (charcoal, bone)
  • Dendrochronology analyzes tree ring patterns to date wooden artifacts
• Relative dating methods establish the order of events or artifacts without assigning specific dates
  • Seriation arranges artifacts in a sequence based on changes in style or frequency over time
• Context refers to the relationship between artifacts, features, and their surroundings
  • Primary context indicates an artifact is in its original place of deposition
  • Secondary context suggests an artifact has been disturbed or moved from its original location
• Provenience denotes the three-dimensional location of an artifact or feature within a site
• Taphonomy studies the processes that affect an artifact or site from its initial deposition to its discovery

Historical Context of Archaeological Methods

• Early antiquarianism (16th-18th centuries) focused on collecting artifacts for private collections or curiosity cabinets
• The Enlightenment (18th century) sparked a more systematic approach to studying the past
  • Emphasis on empirical evidence and scientific reasoning
• The Three Age System, developed by Christian Jürgensen Thomsen, divided prehistory into Stone, Bronze, and Iron Ages
  • Based on the idea that technology progressed from stone to metal tools over time
• Nationalism and colonialism (19th-early 20th centuries) influenced archaeological practices and interpretations
  • Archaeology used to support national identities and justify colonial expansion
• The development of stratigraphy and typology in the 19th century laid the foundation for modern archaeological methods
• The introduction of absolute dating methods (radiocarbon dating) in the mid-20th century revolutionized archaeological chronologies
• Processual archaeology (1960s-1970s) emphasized scientific methods and hypothesis testing
  • Focus on cultural processes and systems rather than individual artifacts or sites
• Post-processual archaeology (1980s-present) critiques and expands upon processual approaches
  • Considers multiple interpretations, social and symbolic meanings, and the role of the archaeologist in shaping knowledge

Field Survey Techniques

• Pedestrian survey involves systematically walking over an area to identify and record archaeological sites and artifacts
  • Transects are parallel lines along which surveyors walk to ensure even coverage
  • Spacing between surveyors depends on the desired level of detail and terrain
• Aerial survey uses aircraft or drones to identify sites and features from above
  • Cropmarks, soilmarks, and shadowmarks can reveal buried features (walls, ditches)
• Geophysical survey employs non-invasive methods to detect subsurface features without excavation
  • Magnetometry measures variations in the earth's magnetic field caused by buried features
  • Ground-penetrating radar (GPR) uses radar pulses to create a profile of subsurface anomalies
  • Resistivity survey maps differences in electrical resistance of the soil, indicating potential features
• Satellite imagery analysis uses high-resolution images to identify sites, features, and landscape patterns
  • Multispectral imaging can detect subtle differences in vegetation and soil
• Underwater survey techniques locate and assess submerged sites and shipwrecks
  • Side-scan sonar creates images of the seafloor using sound waves
  • Sub-bottom profiling provides a cross-section of sediment layers beneath the seafloor
• Predictive modeling uses environmental and cultural variables to predict the likelihood of site presence in a given area
• Survey data is recorded using GPS, total stations, and geographic information systems (GIS) for spatial analysis and mapping

Excavation Strategies

• Stratigraphic excavation removes layers of soil in reverse order of deposition to maintain context
  • Arbitrary levels (5 or 10 cm) are used when natural strata are not visible
• Single context recording treats each deposit or feature as a discrete unit
  • Each context is excavated and recorded separately, regardless of thickness
• Open area excavation exposes large horizontal areas to understand spatial relationships between features
  • Requires careful planning and management to maintain stratigraphic control
• Quadrant method divides a site into four quarters, excavating opposite quadrants to create a cross-section
  • Allows for the identification of vertical and horizontal relationships
• Trench excavation involves digging long, narrow trenches to identify site boundaries and stratigraphy
  • Provides a cross-section of the site but may miss important features
• Underwater excavation techniques adapt land-based methods for submerged sites
  • Dredging removes sediment to expose artifacts and features
  • Airlift systems use compressed air to suction sediment and small artifacts
• Screening of excavated soil helps recover small artifacts and ecofacts
  • Mesh size (1/4 inch, 1/8 inch) depends on the desired level of recovery
• Flotation separates organic remains (seeds, charcoal) from soil using water
  • Light fraction contains floating material, while heavy fraction sinks

Artifact Analysis and Dating Methods

• Typological analysis classifies artifacts based on shared attributes (form, decoration, material)
  • Used to establish chronologies and cultural affiliations
• Functional analysis examines the use and purpose of artifacts
  • Use-wear analysis studies microscopic traces of wear to infer artifact function
  • Residue analysis identifies organic remains (blood, plant fibers) on artifact surfaces
• Technological analysis investigates the manufacturing process and techniques used to create artifacts
  • Chaîne opératoire approach examines the sequence of actions involved in artifact production
• Compositional analysis determines the chemical and physical properties of artifacts
  • X-ray fluorescence (XRF) identifies the elemental composition of materials
  • Neutron activation analysis (NAA) provides a more detailed chemical characterization
• Radiocarbon dating measures the decay of carbon-14 in organic materials to determine age
  • Accelerator mass spectrometry (AMS) allows for the dating of small samples
• Dendrochronology dates wooden artifacts by matching tree ring patterns to a master chronology
• Thermoluminescence dating measures the accumulated radiation in ceramics and other heated materials
• Optically stimulated luminescence (OSL) dating determines the last time sediments were exposed to sunlight

Maritime Archaeology Approaches

• Shipwreck archaeology investigates the remains of vessels and their contents
  • Provides insights into maritime technology, trade, and cultural interactions
• Underwater survey techniques (side-scan sonar, sub-bottom profiling) locate and assess submerged sites
• Excavation of shipwrecks requires specialized equipment and techniques
  • Cofferdam excavation involves building a watertight enclosure around the site
  • Underwater dredging removes sediment to expose the wreck and artifacts
• Conservation of waterlogged artifacts is crucial to prevent deterioration
  • Polyethylene glycol (PEG) treatment stabilizes wood by replacing water in cell walls
  • Electrolysis removes salts and concretions from metal artifacts
• Study of ship construction techniques and materials provides insights into shipbuilding traditions and innovations
  • Timber analysis can identify wood species and origin
  • Fastener analysis examines the type and placement of nails, bolts, and treenails
• Artifact analysis of cargo, personal possessions, and ship's equipment reveals information about trade, daily life, and social status
• Integration of historical records (manifests, logs, letters) with archaeological evidence provides a more comprehensive understanding of maritime activities

Data Recording and Documentation

• Context sheets record the details of each excavated context (soil type, inclusions, finds)
  • Harris matrix diagrams the stratigraphic relationships between contexts
• Artifact cataloging systematically records the attributes and provenience of each find
  • Standardized terminology and classification systems ensure consistency
• Field notes provide a daily record of observations, interpretations, and decisions made during excavation
  • Include sketches, measurements, and photographs
• Photographic documentation captures visual information about the site, features, and artifacts
  • Aerial photography provides an overview of the site and its surroundings
  • Close-up photography records details of individual artifacts and features
• Measured drawings accurately depict the shape, size, and spatial relationships of features and artifacts
  • Plan drawings show the horizontal layout of a site or feature
  • Section drawings illustrate the vertical stratigraphy and relationships between contexts
• 3D scanning and photogrammetry create high-resolution digital models of sites and artifacts
  • Allow for detailed analysis, visualization, and preservation of archaeological data
• Geographic Information Systems (GIS) integrate and analyze spatial data from various sources
  • Create maps, perform spatial analyses, and model past landscapes and site distributions
• Databases organize and store archaeological data for easy retrieval and analysis
  • Enable the identification of patterns, relationships, and trends within the data

Ethical Considerations in Exploration-Era Archaeology

• Looting and uncontrolled excavation of sites destroys context and information
  • Encourages the illegal antiquities trade and deprives communities of their cultural heritage
• Colonialism and nationalism have influenced the practice and interpretation of archaeology
  • Archaeology has been used to justify colonial expansion and support nationalist narratives
  • Repatriation of artifacts and human remains to descendant communities is an ongoing issue
• Collaboration with Indigenous communities is essential for ethical archaeological practice
  • Incorporates Indigenous knowledge, perspectives, and values into research and interpretation
  • Ensures that archaeological work benefits and respects the rights of descendant communities
• Public outreach and education promote the understanding and appreciation of archaeological heritage
  • Engages local communities in the protection and stewardship of sites and artifacts
• Sustainable tourism balances public access with site preservation and conservation
  • Minimizes the impact of visitor traffic on sensitive sites and artifacts
• Underwater cultural heritage is protected by international conventions and national laws
  • UNESCO Convention on the Protection of the Underwater Cultural Heritage (2001) sets standards for the responsible management of submerged sites
• Publication and dissemination of research results make archaeological knowledge accessible to the public and the scientific community
  • Open access and digital archives facilitate the sharing and preservation of data
• Professional codes of ethics guide the conduct of archaeologists and promote responsible practice
  • Society for American Archaeology (SAA) and World Archaeological Congress (WAC) have established ethical principles for the discipline