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Covers the basics of archaeological techniques and Analysis
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Excavation Techniques Excavation Techniques and Analysisand Analysis
Recovering Fossil FormsRecovering Fossil Forms
Fundamentals of ArchaeologyFundamentals of Archaeology
Site discovery and selectionSite discovery and selection Excavation of artifacts, ecofacts, and featuresExcavation of artifacts, ecofacts, and features Analysis for dates, attributes, and environmentAnalysis for dates, attributes, and environment
How are Sites Formed?How are Sites Formed?
Taphonomy: Study of how lifeforms or Taphonomy: Study of how lifeforms or artifacts wound up at a particular locationartifacts wound up at a particular location
Fossils:Fossils: Remains of life form from the pastRemains of life form from the past Petrification: replacement of bone with mineral or Petrification: replacement of bone with mineral or
stonestone
How are Items Preserved?How are Items Preserved?
Some materials resist deterioration:Some materials resist deterioration: Bone: Skulls and teethBone: Skulls and teeth Stone or Metal (tools, ornaments)Stone or Metal (tools, ornaments) Seeds, with protective coversSeeds, with protective covers
Others may be preserved byOthers may be preserved by Arid climates (Peruvian coast)Arid climates (Peruvian coast) Water: Planks in Lakes in FranceWater: Planks in Lakes in France Peat moss: the “Bog People”Peat moss: the “Bog People”
More Examples of PreservationMore Examples of Preservation
Waterlogged Sites: Bog People, DenmarkWaterlogged Sites: Bog People, Denmark Arid Sites: Puruchucho-Huaqerones Arid Sites: Puruchucho-Huaqerones
Mummies, PeruMummies, Peru Cold Sites: The Iceman, Italian AlpsCold Sites: The Iceman, Italian Alps Volcanic Ash, Cerén, El SalvadorVolcanic Ash, Cerén, El Salvador
Site DiscoverySite Discovery
Lucky findsLucky finds Consulting available sources: studies, records, Consulting available sources: studies, records,
even older informantseven older informants Maps and aerial photographsMaps and aerial photographs Geographical Information Systems/Remote Geographical Information Systems/Remote
SensingSensing
Site SelectionSite Selection
Learning everything possible about each siteLearning everything possible about each site Selecting as large and representative a site as Selecting as large and representative a site as
possiblepossible Preliminary work: surface finds, features, Preliminary work: surface finds, features,
perhaps test pits or trenchesperhaps test pits or trenches Problem-Oriented Research and Deliberate Problem-Oriented Research and Deliberate
Surveys: Hadar, EthiopiaSurveys: Hadar, Ethiopia
Survey: Mapping, Part 1: Survey: Mapping, Part 1: General General
First principle: Digging is destructive--record First principle: Digging is destructive--record everything!everything!
MappingMapping Latitude, longitude, and elevationLatitude, longitude, and elevation Benchmarks or featuresBenchmarks or features
MeasurementsMeasurements Horizontal Horizontal VerticalVertical
Survey: Mapping Part 2: Survey: Mapping Part 2: Horizontal MeasurementHorizontal Measurement
Select and draw west-east (X-axis) and north-Select and draw west-east (X-axis) and north-south (Y-axis) baselines from south (Y-axis) baselines from primary site primary site datum datum
Mark off intervals at meters and centimeters Mark off intervals at meters and centimeters from baselinesfrom baselines
Label the intervals along axes of the grid by Label the intervals along axes of the grid by letters, numbers, or bothletters, numbers, or both
Adapt procedure according to topographical or Adapt procedure according to topographical or archaeological featuresarchaeological features
Survey: Mapping Part 3: Survey: Mapping Part 3: Vertical MeasurementsVertical Measurements
Surveying using transit or alidade and Surveying using transit or alidade and measuring rodmeasuring rod
Vertical base: benchmark or permanent feature Vertical base: benchmark or permanent feature of known elevationof known elevation
Convert measures to meters above sea level.Convert measures to meters above sea level.
Survey: Test pits and trenchesSurvey: Test pits and trenches
Test pits provide sample of site stratigraphyTest pits provide sample of site stratigraphy Stratigraphy: Stratigraphy: profile of two or more layers ofprofile of two or more layers of
Natural sedimentNatural sediment Human remains and artifactsHuman remains and artifacts
Test pits provide sample of overall siteTest pits provide sample of overall site Test Trenches reveal stratigraphyTest Trenches reveal stratigraphy
Tools for ExcavationTools for Excavation
Dental picks or paint brushesDental picks or paint brushes Ice picksIce picks Tweezers (fragile objects)Tweezers (fragile objects) Trowels (pointed and square)Trowels (pointed and square) Shovels (pointed and square-nosed)Shovels (pointed and square-nosed) Heavy equipment (backhoes)Heavy equipment (backhoes) Buckets and ScreensBuckets and Screens
Vertical Excavation: Some “Laws”Vertical Excavation: Some “Laws”
Law of Association:Law of Association: Artifacts found at the same stratum (layer) are in Artifacts found at the same stratum (layer) are in
association with one anotherassociation with one another Artifacts found at different strata are not in association Artifacts found at different strata are not in association
with one anotherwith one another
Law of Superposition: Geological layers are Law of Superposition: Geological layers are stratified one upon anotherstratified one upon another
Lower strata are older than higher onesLower strata are older than higher ones
Uniformitarianism: Geological processes similar Uniformitarianism: Geological processes similar throughout timethroughout time
Vertical Excavation: Vertical Excavation: StratigraphyStratigraphy
Layer deposited in chronological order: lowest Layer deposited in chronological order: lowest layer is oldest and so on.layer is oldest and so on.
Disturbances can change stratigraphyDisturbances can change stratigraphy Erosion from hillside: oldest is top layerErosion from hillside: oldest is top layer Structure foundation disturbs layersStructure foundation disturbs layers Burrowing animals may move objectsBurrowing animals may move objects Then there are golddiggers and pothuntersThen there are golddiggers and pothunters
Vertical Excavation: Procedure: Vertical Excavation: Procedure:
Each artifact is recorded and removedEach artifact is recorded and removed Photographed, sketched, or describedPhotographed, sketched, or described Vertical and horizontal positionVertical and horizontal position
Soils analyzed for chemistry, pollen, etcSoils analyzed for chemistry, pollen, etc Associations between artifacts are recordedAssociations between artifacts are recorded
Assumption: artifacts found at same layer occurred Assumption: artifacts found at same layer occurred at same time periodat same time period
Vertical Excavation: ProveniencingVertical Excavation: Proveniencing
Definition: recording artifacts in three-Definition: recording artifacts in three-dimensional spacedimensional space
Transit and stadia rod: record is set from a Transit and stadia rod: record is set from a secondary datum pointsecondary datum point
Theodolite: records the position of an artifact Theodolite: records the position of an artifact using a laser bouncing off a prism of known using a laser bouncing off a prism of known heightheight
Horizontal Excavation: Horizontal Excavation: ProcedureProcedure
As each layer or stratum is excavated, it is As each layer or stratum is excavated, it is removedremoved
Same procedure of excavation is repeated for Same procedure of excavation is repeated for next layernext layer
One or two layers: prefer horizontal excavation One or two layers: prefer horizontal excavation to get lay of the siteto get lay of the site
Different samples are taken for different layers: Different samples are taken for different layers: soil, pollen, charcoal, bonesoil, pollen, charcoal, bone
Some layers may be left for controlSome layers may be left for control
Analysis: Aims and ObjectivesAnalysis: Aims and Objectives
DatingDating Artifact: classificationArtifact: classification Bone analysisBone analysis PaleobotanyPaleobotany Palynology (pollen analysis)Palynology (pollen analysis) PaleozoologyPaleozoology StructuresStructures Other featuresOther features
Overview of DatingOverview of Dating
UnifomitarianismUnifomitarianism Relative DatingRelative Dating
StratigraphyStratigraphy AssociationAssociation
Absolute DatingAbsolute Dating CalendricalCalendrical Natural FeaturesNatural Features IsotopicIsotopic
Dating: UniformitarianismDating: Uniformitarianism
Uniformitarianism vs. CatastrophismUniformitarianism vs. Catastrophism Uniformitarianism: All geological processes--Uniformitarianism: All geological processes--
erosion, weathering--observable today have erosion, weathering--observable today have always been present and at the same ratealways been present and at the same rate
Uniformitarianism is the basis of dating.Uniformitarianism is the basis of dating. Catastrophism: Changes have been sudden and Catastrophism: Changes have been sudden and
have occurred at different rates in the past have occurred at different rates in the past from those of the present.from those of the present.
Relative DatingRelative Dating
Stratigraphy: Stratigraphy: Establishment of sequences by Establishment of sequences by soil stratasoil strata Exceptions: soil disturbance, erosion.Exceptions: soil disturbance, erosion.
Law of Association: Dating of finds within a Law of Association: Dating of finds within a stratumstratum
Chronometric Associations: Chronometric Associations: Relative and Absolute Dating Relative and Absolute Dating
Combined?Combined? Basic principle:Basic principle: Materials associated with Materials associated with
other materials of known age are the same age other materials of known age are the same age rangerange Bottle styles and clay pipes .Bottle styles and clay pipes . Gravestones in Stoneham, MA (Deetz)Gravestones in Stoneham, MA (Deetz)
Absolute Dating: CalendricalAbsolute Dating: Calendrical
Entails use of traditional calendarsEntails use of traditional calendars MayanMayan
Long Count:Long Count: Beginning date fixed at 3113 BC Beginning date fixed at 3113 BC Calendar Rounds: Calendar Rounds: 260- and 365-day calendars260- and 365-day calendars
Egyptians: Egyptians: 332 BC Conquest by Alexander the Great332 BC Conquest by Alexander the Great Traced back through recorded dynastiesTraced back through recorded dynasties Astronomical events checked by present data Astronomical events checked by present data
Others: Others: Chinese, Romans, GreeksChinese, Romans, Greeks
Absolute Dating: Natural Absolute Dating: Natural FeaturesFeatures
Dendrochronology: Dendrochronology: Tree ring datingTree ring dating Tree rings vary from year to yearTree rings vary from year to year Local stumps or timber compared with master Local stumps or timber compared with master
sequence (e.g., Univ. of Arizona)sequence (e.g., Univ. of Arizona) Varve analysis: Varve analysis: Clay deposits in lakes from Clay deposits in lakes from
melting ice.melting ice. Patterns also differ yearlyPatterns also differ yearly Likewise compared with master chart.Likewise compared with master chart.
Absolute Dating: Isotopic Absolute Dating: Isotopic TechniquesTechniques
Common PrinciplesCommon Principles Isotopes: Isotopes: Radioactive variants of elements (e.g. Radioactive variants of elements (e.g.
carbon, potassium)carbon, potassium) Isotopes decay from radioactive to nonradioactive Isotopes decay from radioactive to nonradioactive
element element They do so at a constant rateThey do so at a constant rate
Half Life: Half Life: The period in which radioactivity The period in which radioactivity rate reaches half the original rate.rate reaches half the original rate.
Isotopic Techniques: Radiocarbon Isotopic Techniques: Radiocarbon DatingDating
Carbon Carbon is found in all lifeformsis found in all lifeforms Carbon 12Carbon 12 is the stable element is the stable element All living things accumulate All living things accumulate Carbon 14Carbon 14 At death, carbon 14 decays at a constant rate to At death, carbon 14 decays at a constant rate to
Carbon 12Carbon 12 It reaches half the rate of original radioactivity in It reaches half the rate of original radioactivity in
5730 years5730 years At 11460 years, radioactivity is half the second At 11460 years, radioactivity is half the second
rate--and so onrate--and so on
Isotopic Techniques: Accelerator Isotopic Techniques: Accelerator Mass SpectrometryMass Spectrometry
In dating, a sample is cleaned then burned to In dating, a sample is cleaned then burned to produce gasproduce gas
Proportion of C14 to C12 is then counted Proportion of C14 to C12 is then counted using Geiger counterusing Geiger counter
Several grams are required for the countSeveral grams are required for the count Accelerated Mass Spectrometer: Accelerated Mass Spectrometer: counts counts
individual moleculesindividual molecules Advantage: High accuracy, less materialAdvantage: High accuracy, less material
Isotopic Techniques: Isotopic Techniques: Radiopotassium DatingRadiopotassium Dating
Half life: Half life: 1.3 billion years1.3 billion years Potassium is found in granite, basalt, clayPotassium is found in granite, basalt, clay Potassium 40 decays to a gas, Argon 40Potassium 40 decays to a gas, Argon 40 Argon 40 accumulate when a rock is formedArgon 40 accumulate when a rock is formed Disadvantage: materials less than 500,000 Disadvantage: materials less than 500,000
years old cannot be datedyears old cannot be dated
Other Absolute Dating TechniquesOther Absolute Dating Techniques
Electronic Spin Resonance:Electronic Spin Resonance: Accumulation of unpaired electrons in crystals in tooth Accumulation of unpaired electrons in crystals in tooth
enamel and other items with calcium (inaccurate in enamel and other items with calcium (inaccurate in bone)bone)
Geomagnetism: Geomagnetism: Alignment of particles on magnetic rock; this is Alignment of particles on magnetic rock; this is
approximate and there are few labsapproximate and there are few labs Obsidian Hydration:Obsidian Hydration:
Reaction with water; measured by thickness of Reaction with water; measured by thickness of accretion.accretion.
Conclusion: DatingConclusion: Dating
All techniques are problematicAll techniques are problematic Appropriate labs may be rareAppropriate labs may be rare Analyzable material must be present: no volcanic Analyzable material must be present: no volcanic
rock, no radiopotassium datesrock, no radiopotassium dates Inherent problems: radiocarbon dating may be off Inherent problems: radiocarbon dating may be off
by centuriesby centuries Best strategy: use several techniquesBest strategy: use several techniques
e.g. dendrochronology with radiocarbon.e.g. dendrochronology with radiocarbon.