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If you want to cut down a tree… Or build a canoe… Or wage war…. Or scrape meat out of a coconut… Or cut meat from a pig… You need to make tools. Lacking metal, (pre-contact) Polynesians made tools out of stone. Figures from Encyclop é die de la Polyn é sie.
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If you want to cut down a tree… Or build a canoe… Or wage war…. Or scrape meat out of a coconut… Or cut meat from a pig… You need to make tools
Lacking metal, (pre-contact) Polynesians made tools out of stone Figures from Encyclopédie de la Polynésie
Is one stone as good as another? • Vesicular pāhoehoe lava makes a lousy adze, but an excellent grinding or • polishing stone • Coarse-grained rocks make crumbly adzes, but excellent sinkers and lures • Glass is best for cutters and scrapers (but hard to find in large pieces) What makes a good source rock for making an adze? 1. Fine-grained, with even sized grains is best - need to be able to fabricate and hold a fine edge without breaking 2. Not many vesicles(bubbles are structural defects) ‘a‘ā flow interiors, dikes, some massive alkalic lavas 3. Not many large crystals (crystals are defects too) most postshield alkalic rocks; some shield lavas 4. Fractures previously fractured outcrops save labor columnar jointed lavas and dikes were widely exploited sources unusual cooling of Mauna Kea lava that ponded against ice
Making tools from raw stone The stone must withstand fabrication And not break when being used
The Role of Geochemistry and Petrology • Any rock can be described in terms of: • Texture • Mineralogy • Chemical Composition Although Polynesians largely selected rocks based on physical properties (texture and fracture characteristics), the best method for “sourcing” artifacts is through the use of quantitative geochemical data. Matches of artifacts to source Does an artifact have the same texture, mineralogy and chemical composition within uncertainties to a known source (outcrop, volcano, island) Chemical data are fully quantitative, allowing for realistic uncertainty estimates to be determined.
Sources of Uncertainty Analytical Uncertainty Quarry Variability Different analytical methods have different inherent “errors” Two critical analytical issues are precision (reproducibility) and accuracy (correctness) How variable is the actual source area? This can only be determined from dedicated investigations of specific quarries Chemical Data for Eiao Adze Quarry Average of 17 analyses ± 1 standard deviation wt % ppm
Archeologists use artifacts to make interpretations about “spheres of influence” Weisler, 1998 This map shows some known and suspected interactions based on ethnohistoric sources and documented transfers of artifacts (mainly lithic) These interpretations are largely based on macroscopic appearance or stylistic similarities
Rock sections viewed through the microscope Chemical analyses of rocks 1986-602 adze (large adze found in Honolulu Harbor) apatite crystals C-159 (sample collected by G. A. Macdonald from Pu‘u Pāpa‘i, Moloka‘i) * total Fe as FeO LOI = loss on ignition at 900°C Pu‘u Pāpa‘i, E. Moloka‘i
Known Polynesian Adze Quarries (not including New Zealand) By far the three largest (export) quarries are Hawai‘i – 15 Samoa (Tutuila) – 4 Cook Is. – 4 Austral Is. – 3 Pitcairn – 2 Rapa Nui – 5 Marquesas – 4 Society Is. – 5 Mauna Kea (Hawai‘i) Tataga matau (Samoa) Eiao (N. Marquesas)
Geochemical Evidence of Interaction Major interaction within archipelagos; limited interaction between archipelagos • Tataga-matau adzes in N. Cook Is. • Tataga-matau maybe in Line Is. • Eiao throughout Marquesas • Eiao on Moorea • Eiao on Mangareva (Gambier) • Pu‘u Wa‘awa‘a obsidian in Halawa (O‘ahu) • Pu‘u Mō‘iwi (Kaho‘olawe) adze on Kaua‘i; Lāna‘i adze on Kohala • Mauna Kea adze on O‘ahu • Moloka‘i adze on O‘ahu and Kaua‘I • Possible Hawaiian adze in Tuamotus • Pitcairn obsidian on Henderson atoll Don’t know: - Process of transfer (commercial enterprise, bartar, exchange) - Organizational system for quarries (ownership if any, division of labor)
Quarry Types (from a geological perspective) • Outcrops: • Columnar lavas (Tahiti) • Dikes (Tahiti and elsewhere - see also residual dike rock) • Massive lava flows (W. Moloka‘i, Kailua, Kaho‘olawe, Haleakalā, Rurutu) • Massive flow chilled against ice (Mauna Kea) • Residual Deposits • Dike boulders in streams on Ra‘iatea • Major quarry of dike rocks in alluvial (stream) deposit on Eiao, N. Marquesas Columnar jointed lava, East Maui
Eiao, N. Marquesas Selective mining of dike rocks in stream deposit
The Tuamotu example • all atolls – no local volcanic sources • Geochemical evidence suggests some adzes from Society Is., Pitcairn, N. Marqueseas (Eiao) and possibly Hawai‘i Collerson and Weisler, 2007
Archeological Investigations at Hanamiai, Tahuata, Marquesas B. Rolett, Univ. Hawai‘i, Dept. Anthropology Evidence for major breakdown in the system of interaction ~1450 A.D.
Adze Quarries of West Moloka‘i Ka Lua Ko‘i “The adze pit” 14 separate adze sources known Most quarries on postshield lavas, but not all One dike quarry
Pu‘u Mō‘iwi adze quarry – Kaho‘olawe At least one Mō‘iwi adze found in an archeological site on Kaua‘i
Mauna Kea Adze Quarry Glacially chilled hawaiite lava flow
Hawaiian Sources Large squares denote documented quarries; small squares are other sources Note – at least one significant quarry on each inhabited island