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[en] The aim of this paper is to present the methodology deployed in the Chasicó basin (southern Pampas, Argentina) in order to discuss the differential contribution of primary and secondary lithic sources in the spatia and technological organization of late Holocene hunter-gatherers societies. Such methodology is based on the comparative analysis of curves constructed with data obtained from virtual transects traced over continuous spatial models representing different properties of regional lithic landscapes. Those models were created by interpolation using a technique called Inverse Distance Weighted (IDW) from scattered information recovered at point locations (i.e. archaeological sites and localities; n = 12). Investigated raw materials were rhyolites and two varieties of quartzites, and the monitored variables were relative frequency (F%), relative weight (P%) and cortex index (IC). Our results suggest that both varieties of quartzites were mainly procured from secondary sources distributed along the basin and that rhyolites were mostly obtained from primary sources located at the headwaters.
[es]El objetivo de este trabajo es presentar la metodología implementada en la cuenca del Arroyo Chasicó (sur de la Región Pampeana Argentina), orientada a discutir el uso diferencial de fuentes de materias primas líticas primarias y secundarias en relación con la organización espacial y tecnológica en sociedades cazadoras-recolectoras del Holoceno tardío. La metodología se basa en el análisis comparativo de curvas construidas con datos procedentes de transectos virtuales, trazados sobre modelos espaciales continuos representando diferentes propiedades de los “paisajes líticos” del área de estudio. Tales modelos se generaron por interpolación mediante la técnica denominada Inverse Distance Weighted (IDW) a partir de información procedente de localizaciones puntuales (i.e. sitios y localidades arqueológicos; n = 12). Las materias primas investigadas fueron riolitas y dos variedades de cuarcita y las variables consideradas fueron frecuencia relativa y peso relativo, expresadas ambas en términos porcentuales (F% y P%, respectivamente) e índice de corteza (IC). Los resultados obtenidos indican que, para ambas variedades de cuarcitas, la explotación de fuentes secundarias —distribuidas a lo largo de la cuenca— fue mayor que la de las primarias, mientras que las riolitas fueron obtenidas, principalmente, de las fuentes primarias situadas en las cabeceras.
[en] The chemical compositions of 42 obsidian pre-Hispanic artifacts from Tancama and Purisima, both archaeological sites of La Sierra Gorda Valleys, Mexico, were analyzed by PIXE technique. These obsidians came from four sources: Sierra de Pachuca Hidalgo, Paraiso Queretaro, Ucareo Michoacan and mainly from Zacualtipan/Metzquititlan Hidalgo. According to archaeological evidences, La Sierra Gorda valleys participated in commercial exchange with other regional sites, from Classic to Post-classic periods (A.D. 300-1500).
[en] Agroecological studies of the of the Swat River catchment area showed that the terrestrial ecosystem of the area is divided into subtropical, humid temperate, cool temperate, cold temperate, subalpine, alpine and cold desert zones. Indicator species along with their altitudinal limits are specified for each zone. Unplanned population growth, agriculture extension, habitat losses, deforestation, environmental pollution and unwise use of natural resources are threats to the natural biodiversity of these zones. Its severity is very evident in the subtropical and humid temperate zones. The losses encountered to the biodiversity of the area under the influence of various anthropogenic stresses are highlighted. (author)
[en] In archaeometric data set it was verified by statistical tests that some variables almost never follow a multivariate normal distribution using logarithmic transformation or other. This work presents a multivariate Box-Cox transformation for Mardia's and Royton's tests for a data set of fifty ceramic fragments from archaeological site Justino, Xingo, Brazil, and one clay sample collected near of the site. The samples were analyzed by instrumental neutron activation analysis, INAA. The study was made using companion to applied regression package from R software and was tested by Hotelling's T"2 statistics. (author)
[en] Archaeological excavation of the Institute of Archaeology and Ethnology (Polish Academy of Sciences, PAN) at several Iron Age sites located in West Poland and South Germany has allowed the recovery of an important set of coloured glass beads mostly decorated (6th–4th centuries BC). The present paper summarises the results obtained through the chemical and microstructural characterisation of such beads. The research was carried out by binocular microscope observations, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectrometry and visible spectrophotometry. The main objective was to attain information on the production technology and conservation state of these beads. The results indicated that all them were produced with soda lime silicate glass, even though two groups can be separated: (i) beads containing high MgO percentages made from plant ashes as an alkaline source, and (ii) beads containing low MgO percentages made from natron as an alkaline source. As regards decorations, opaque white was obtained from tin oxide, turquoise blue from Cu2+-ions, and opaque yellow from lead antimonate. Additionally, results showed microstructural and microcrystalline differences between some glass beads studied here and other glass beads from Mediterranean areas, dated in the same chronological period. This fact pointed out the valuable role given to these beads by Iron Age communities from Central Europe. (Author)
[en] Complete text of publication follows. Four kilns and a collection of baked bricks from Italian archaeological sites have been studied for archaeointensity determination. Most of the sites are dated based on archaeological information and their dates range from 500 to 800 AD and 1500 to 1700 AD. Rock magnetic studies identify magnetite, Ti- magnetite and hematite as the main magnetic minerals. Magnetic susceptibility behavior versus temperature shows a good reversibility of the heating and cooling curves. Archaeointensity experiments were performed using the Thellier modified by Coe method. Corrections for the anisotropy of thermoremanent magnetization (TRM) upon the archaeointensity values have been applied after the determination of the TRM anisotropy tensor in each specimen. In some cases the effect of TRM anisotropy is important and the corrected and uncorrected mean intensities differ by almost 9%. The effect of cooling rate on the TRM acquisition was also determined. This later is very low in all samples. For one kiln, archaeointensity determination was unsuccessful; for all studied samples low-quality, non linear Arai plots were obtained and the results were rejected. For the rest of sites, 4 to 13 samples were used to calculate the site mean intensity and in all cases high quality results were obtained. These results, even if not numerous, contribute to the Italian archaeointensity dataset that includes 102 previously published data, from which however only 15 come from archaeological material. All the other Italian archaeointensity data come from volcanic rocks and cover the time interval from 1169 to 1983 AD. The time period 100-1000 AD was previously completely uncovered by data. Two of the new results presented here, coming from two kilns dated on 6th and 8th century AD, are the first data for this period and give virtual axial dipole moments of 10.4 x 1022 Am2 and 12.4 x 1022 Am2, respectively. Cleary more data are still needed in order to describe the geomagnetic field intensity variation in Italy during the last 2000 years.
[en] The microbial communities associated to Uxmal Mayan monuments (Yucatan, Mexico) and their role in stone deterioration were preliminary characterized by chemical, biochemical, microbiological, microscopical and surface analysis methods under two climatic seasons (1997). The organic matter and organic carbon and nitrogen were in the range of those reported for other stone buildings, indicating that oligo trophic conditions prevail at Uxmal. Quantitative differences in microbial biomass was higher at indoor section were the organic matter content was the highest and micro-environmental conditions (availability of water and protection to direct sunlight) are more suitable for microbial growth. The microbiological analysis underestimated the microbial biomass, as revealed by biochemical approaches. Nitrate and nitrite-oxidizing, metilotrophic and heterotrophic bacteria and fungi were detected in most surfaces. The heterotrophic bacteria were the most abundant microbial group (microbiological data). However, the chlorophyll profiles and Scanning Electron Microscopy showed that the microalgae are the most abundant colonizers in Uxmal stone buildings. EDAX analysis showed that the most surfaces were covered by an organic layer (cells and exo polymers). Gypsum was found in few samples. The large photo trophic biomass seems to play a role in stone bio deterioration by supporting growth of heterotrophic microorganisms (bacteria and fungi) which are known to produce organic acids leading to calcite dissolution and cations chelation. Further studies are being carried out in order to determine the role of exo polysaccharides which are thought to play a role in chemical degradation of limestone substrates in Uxmal. (Author)
[en] Thermoluminescence dating is one of the known techniques that have been established in many laboratories across the region. This technique is capable of dating the archaeological ceramic base materials and provide an absolute measurement with an accuracy of ±15%. The study involves the dating of pottery from a historical site at Sungai Mas, Mukim Kota, Daerah Kuala Muda, Kedah. Pieces of broken pottery of archaeological sample excavated by the Museum Department and Antiquity (JMA) have been dated using the thermoluminescence detector (TLD) techniques at MINT laboratory. A TLD dosemeter of LiF chips is used for the measurement of background and sample dose measurement. The preparation of sample and the calibration techniques for the estimation of palaedose or dose presented in the sample since distant past is established. Results indicate that the samples are in the era of civilization from 200 BP to 1600 BP. Error factors associated in the measurement procedures were identified and discussed. (Author)
[en] The sedimentary infill bearing the archaeological and anthropological record of the Ossuary Gallery (the Sidrón cave) shows high complexity in both sediment types and their spatial distribution in the cavity. The main factors that govern this complexity are the episodic and highly energetic nature of the recorded sedimentary infill units and the irregular geometry of the gallery itself, which significantly compartmentalized areas of deposition. Briefly, all types of typical allochthonous detrital material deposits in karst environments are represented in the Ossuary Gallery; from well-sorted fine-grained sediment facies representative of backswamp (clays of the unit O) or slackwater (Unit IV), to poorly-sorted coarse-grained deposits corresponding to mudflows and debris flows (Unit II and Unit III base), and typical channel facies composed of laminated sands and silts (units I and II). The bone and lithic remains are concentrated in unit III. The source area is above the Ossuary Gallery, at the intermediate or higher karst levels. The input of archeological material to the Ossuary Gallery was triggered in high energy episodes in association to flood events and / or storms.
[es]El relleno sedimentario que alberga el registro arqueológico y antropológico de la Galería del Osario (cueva de El Sidrón) presenta una alta complejidad, tanto en los tipos de sedimentos como en su distribución espacial en la cavidad. Los principales factores que rigen esta complejidad son la naturaleza episódica y altamente energética de gran parte de las unidades litoestratigráficas reconocidas y la irregular geometría del propio conducto, que compartimenta significativamente las áreas de deposición. A modo de resumen puede indicarse que en la Galería del Osario quedan representados todos los tipos de materiales detríticos típicos de depósitos alóctonos en ambiente kárstico; desde materiales bien seleccionados de granulometría fina representativos de facies de encharcamiento (arcillas de la unidad O) o de desbordamiento (Unidad IV), a depósitos groseros mal seleccionados correspondientes a coladas de barro y detritos en masa (Unidad II y base de unidad III), pasando por típicas facies fluvio-kársticas o de canal compuestas por materiales arenosos con laminaciones y estructuras de flujo (unidades I y II). Los restos óseos se concentran en la unidad III. El área fuente se sitúa en cotas superiores a la Galería del Osario, es decir, en los niveles intermedio o superior del sistema kárstico, y el depósito o entrada de material óseo a la Galería del Osario se activaría en episodios de alta energía relacionado con eventos de inundación y/o tormenta.