Obsidian and Ancient Manufactured Glasses

Figures and Tables

ix Figures Figure 1.1. Diagram of a magnetic sector (CAMECA) SIMS instrument . . . . . . . . . . . . . . . . . . . . . 5 Figure 1.2. Diagram of a quadrupolebased SIMS instrument (Phi) . . . . . . . . . . . . . . . . . . . . . 5 Figure 1.3. Photomicrograph of SIMS craters on an oriented obsidian surface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Figure 1.4. Quadrupole SIMS depth profile measurements of hydrated obsidians . . . . . . . . . 8 Figure 1.5. SIMS profiles of laboratory hydrated obsidian samples. . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Figure 1.6. Correlation of hydration layer thickness. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Figure 1.7. AFM image of a conchoidal fractured obsidian surface . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Figure 1.8. AFM image of an obsidian artifact showing roughness due to pitting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Figure 1.9. Comparison of two SIMS profiles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Figure 2.1. Map showing the three main obsidian source areas in Papua New Guinea . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Figure 2.2a. The reproducibility of the SIMS analysis (Igwageta source). . . . . . . . . . . . . . . . 18 Figure 2.2b. Confirmation of the reproducibility of two SIMS runs. . . . . . . . . . . . . . . 19 Figure 2.3. The major element chemistry of the four obsidian sources as shown in this Arrhenius regression diagram. . . . . . . . 21 Figure 2.4. Average curve of 5 scans (A–B) across an external hydration band and average curve of 3 scans (A–D) across an internal fissure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Figure 3.1. A SIMS hydrogen profile. . . . . . . . . . . . . 28 Figure 3.2. A nondimensional profile with Crank’s theoretical curves . . . . . . . . . . . . . . . . . 30 Figure 3.3. A Polarised Light Microscope (PLM) image of a Melian obsidian surface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Figure 3.4. SEM backscattering image of Youra Island (Cyclop’s Cave) Melian obsidian . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Figure 3.5. AFM topographic image. . . . . . . . . . . . 31 Figure 3.6. Linear fit to the hydration region for the calculation of Rstd . . . . . . . . . . . . . . . . 32 Figure 3.7. Savitziky-Golay fit and the first derivative of the Savitziky-Golay. . . . . . . . 33 Figure 3.8. (a) Fitting until the inflection depth; (b) First derivative of the 3rd-order polynomial. . . . . . . . . . . . . . . . . . . . . . . 34 Figure 3.9. Results from the linear regression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Figure 3.10. An ideal SIMS profile. . . . . . . . . . . . . . . . 35 Figure 3.11. Repeated polynomial fittings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Figure 3.12. Hyperbola bell shape, normal and reversed. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Figure 3.13. Screen image of the SIMS-SS software. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Figure 3.14. Fitting with the “fit coef” button of the SIMS-SS software. . . . . . . . . . . . . . . . . . 39 Figure 3.15. Ages calculated with SIMS-SS method versus expected archaeological ages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Figure 3.16. Sensitivity of age for four parameters: ek , Cs , Xs , and Ds,eff . . . . . . . . . . . . . . . . . 42 Figures and Tables x | FIGURES AND TABLES Figure 3.17. Samples without a developed hydration layer compared to a normal diffusion profile (Lamo-5) 43 Figure 3.18. Disturbed SIMS profile: Sample YR-3 from Youra Island, Greece 43 Figure 4.1. Relationship between site altitude and average temperature variation, northern Mojave Desert sample 51 Figure 4.2. Relationship between site altitude and annual temperature variation, northern Mojave Desert sample 51 Figure 4.3. Relationship between site altitude and mean diurnal temperature variation, northern Mojave Desert sample 51 Figure 4.4. Relationship between average annual temperature and annual temperature variation, northern Mojave Desert sample 51 Figure 5.1. Map of East Africa, showing obsidian sources and archaeological sites 58 Figure 5.2. Map of the Lake Naivasha basin in the central Rift Valley of Kenya 59 Figure 5.3. Distance-decay curves for percentages of obsidian in archaeological sites 66 Figure 6.1a and 1b. Relative deviations between the LA-ICP-MS and the p-XRF measurements for strontium and manganese 78 Figure 6.2a and 2b. Relative errors on the p-XRF measurements for strontium and manganese 79 Figure 6.3a. Graph reporting the concentration of rubidium and strontium measured for the samples from Cerro Baúl 80 Figure 6.3b. Graph reporting the concentration of manganese and strontium measured for the samples from Cerro Baúl 80 Figure 6.4a. Graph reporting the concentration of rubidium and strontium measured for the samples from Cerro Mejia and Mejia Lareda 81 Figure 6.4b. Graph reporting the concentration of manganese and strontium measured for the samples from Cerro Mejia and Mejia Ladera 81 Figure 6.5. Examples of projectile point types from Cerro Baúl 83 Figure 7.1. Map of Tiwanaku and other archaeological sites in the Lake Titicaca basin 88 Figure 7.2. Topographic map of archaeological sites within the boundaries of Tiwanaku 88 Figure 7.3. Map showing the locations of obsidian sources mentioned in this study 89 Figure 7.4. Bivariate plot of the elements Cs and Hf measured by NAA on obsidian artifacts 91 Figure 7.5. Bivariate plot of the elements Sc and Eu measured...