Holistic analysis of thin-sections of Early Bronze pottery from Bab edh-Dhra' and Numeira, Jordan.

摘要

This study extends previous investigations of thin-sections of sherds from two Early Bronze towns along the Dead Sea, Bâb edh-Dhrâ' and Numeira. Petrographic analysis, computerized point counts, and SEM with EDS are correlated with other information such as; collection location and period, pottery forms, surface treatments, and construction methods to create a holistic approach to the thin-section analysis. The objective is to understand the advancement of manufacturing techniques, which are built upon the technical discoveries of individual potters and driven by changes in social hierarchy, culture, burial traditions, and economy.; Through standard petrographic techniques, major inclusion groups (Basalt, Limestone, Nubian Sand, Sandstone, and Shale) were identified and split into subgroups. The classification of subgroups within the Nubian Sand Group demonstrated the uniqueness of this group and led to the eventual separation of other quartz-tempered sections into the Sandstone Group. Examination of the Limestone Group subgroups and relative temporal inclusion group abundances reveals the change from experimental pottery manufacturing techniques during EBIB-II, to established production centers during EBIII, to a disrupted pottery tradition during EBIV. Petrographic analysis also identified a previously unknown relationship between the Limestone Group and the Shale Group.; Other interesting grains identified within the thin-sections were quartz with apatite veins, diatoms, and microfossils. Comparison of these grains to local outcrops may help in the understanding of the erosional and depositional environment during the Early Bronze period.; Chemical analysis of dolomite rhombs within thin-sections from pottery of the Limestone Group was performed with an SEM with EDS. From this data it is hypothesized that the presence and possibly the dedolomitization of the rhombs within the limestone temper inhibits decarbonation of the limestone, thus preventing spalling and cracking.; A computer based procedure for measuring voids and quartz temper was developed to replace time consuming point counts. Errors due to measurement algorithms, finite image size, and finite pixel resolution were recognized and corrected for. The data provided by this technique identified differences between Bâb edh-Dhrâ' and Numeira within pottery of the Nubian Sand Group. These differences complicate a previous trade model between the two sites, with production solely at Numeira.