Application of tin to ancient pottery

It has earlier been assumed that the tin cover found on certain antique vases has been attached as a thin foil. In this paper it is shown that the metal may simply have been applied by an immersion technique. Before dipping into the tin melt the pottery must be treated with an adhesion promotor. Animal glue which was known as a binder in ancient times has been found to be useful for the surface treatment.     

Spring temperatures in the Sagehen Basin, Sierra Nevada, CA: implications for heat flow and groundwater circulation

Heat flow in the Sierra Nevada, CA, is low despite its young geologic age. We investigate the possibility that advective heat transport by groundwater flow leads to an underestimate of heat flow in the Sierras based purely on borehole measurements. Using temperature and discharge measurements at springs in Sagehen Basin, we find that groundwater removes the equivalent of approximately 20–40 mW m⁻² of geothermal heat from the basin. This is comparable with other heat flow measurements in the region and indicates that, in this basin, at least, groundwater does transport a significant amount of geothermal heat within the basin. Additionally, we use estimates of the mean residence time of water discharged at the springs along with hourly temperature records in springs to provide constraints on groundwater flow depths within the basin. An analytical model based on these constraints indicates that the heat removed by groundwater may represent 20% to >90% of the total heat flow in the basin. Without better constraints on the regional hydrogeology and the depth of circulation, we cannot determine whether the heat discharged at the springs represents a change in the mode of heat transfer, i.e. from conduction to advection at shallow depths (<100 m) or whether this is a component of heat transfer that should be added to measured conductive values. If the latter is true, and Sagehen Basin is representative of the Sierras, basal heat flow in the Sierra Nevada may be higher than previously thought.     

What do aqueous geothermometers really tell us?

The application of chemical geothermometry to shallow groundwaters or spring discharge assumes that there is minimal mixing or re-equilibration of water as it travels from depth to the surface. In this study, we examine the potential for mixing and re-equilibration by examining heat and fluid flow along crustal-scale faults in tectonic geothermal systems. Numerical modeling results indicate that maximum in situ temperatures could be under-predicted by up to 30% due to mixing of fluids that enter the fault at different depths. This, coupled with the depression of isotherms by downward groundwater flow in the hanging wall, could cause underestimates of maximum circulation depth of greater than 80% in extreme cases. Kinetics does not favor re-equilibration in the shallower portions of faults due to low temperatures and higher fluid velocities. However, in areas of deeper circulation or higher heat flow such reactions are possible.     

Beyond cereals: crop processing and Vitis vinifera L. Ethnography,experiment and charred grape remains from Hellenistic Greece

Archaeobotany, ethnographic observation, and laboratory experimentation are brought together to build model sequences of grape processing parallel to the better studied and reported sequences in existence for cereal processing. A set of such model sequences is developed and presented, and explored in the context of rich archaeobotanical assemblages from the Hellenistic farmstead at Komboloi in Southern Macedonia. We conclude that the remains of pressed grapes are reasonably distinctive, whereas whole grapes and raisins can leave similar material in charred state, requiring close scrutiny for secure separation. Our model sequences are further considered in the light of other sites in which Vitis remains have been variously interpreted, and our own reinterpretations offered.     

Red ochre decorations in Spanish Neolithic ceramics: a mineralogical and technological study

Some Neolithic ceramics from south-eastern Spain have red to brown external decorations called “almagras” (red ochre). The pigment layer is essentially composed of a mixture of clay and iron oxides: haematite (red) and maghemite (brown). It is suggested that maghemite was formed during the firing process of ceramic in a reducing atmosphere. Several laboratory tests have been carried out to obtain maghemite by adding charcoal or pinewood sawdust to similar ceramic pastes. In fact, maghemite was formed, even when the piece was simply covered with pinewood sawdust before firing. The diverse original red colours are due to variations in iron oxide (or calcite) content and to redox conditions in the firing procedure. Brown- coloured ceramics owe their colour to maghemite and must be considered as a “fabrication defect”, due to the position of the ceramic piece in a zone where a reducing atmosphere prevailed in the course of firing.     

Multivariate visualization and analysis of photomapped artifact scatters

Simultaneous analysis of relationships between multiple artifact classes is required for characterization of many types of activity areas. This paper illustrates improved forms of multivariate visualization, spatial analysis and integration of experimental results that are possible with GIS based photomapping. Techniques are demonstrated through analysis of a hearth associated artifact scatter exposed during excavations of a Late Archaic pithouse at Jiskairumoko, Peru. A multivariate density raster is created and additive color visualization is used for simultaneous display of three artifact distributions. Performing unconstrained clustering in a GIS, space is classified by simultaneous relative density relationships between multiple object types.     

旅游预订网站顾客所感知的关系利益对顾客忠诚感的影响——兼论替代者吸引力的调节作用

作者通过对在线旅游预订网站顾客进行实证调研,研究顾客感知的关系利益对顾客忠诚感的影响,以及替代产品／服务吸引力对关系利益与顾客忠诚感之间关系的调节作用。数据分析结果表明：在网络预订环境中,顾客获得的信任利益、社交利益和特殊待遇利益都会对顾客忠诚感产生影响。其中特殊待遇利益对顾客忠诚感的正向影响最大,其次是信任利益,而社交利益会对顾客忠诚感产生负向影响。替代者的吸引力大小对顾客感知的信任利益、社交利益和特殊待遇利益与顾客忠诚感之间的相互关系均有显著的调节作用。论文对研究结果进行了讨论,提出了相关的管理建议。     

The use of electron spin resonance spectroscopy to determine the thermal histories of cereal grains

The thermal histories of archaeological cereal grains have been explored with electron spin resonance spectroscopy by a quantitative study of pyrolysis-induced radical carbon. Comparison with modern samples of heated cereal grain has shown that the g value of the radical carbon signal is characteristic of exposure to a previous maximum temperature, and studies of other signal parameters suggest that further information, such as the duration of previous heating, may be deduced from such studies. The proposed method offers the possibility of quantitatively rigorous measurement in archaeological studies of cultural and technological processes that previously relied upon subjective assessment.     

Split phalanges from archaeological sites: evidence of nutritional stress?

Broken animal phalanges from archaeological sites have been widely used as an indicator of nutritional stress of the prehistoric people due to the low caloric return rate (caloric yield/processing time) of the phalanges. Although it sounds logical, this widely popular argument is based on Binford’s (1978) interview with the Nunamiut and lacks empirical support. In this study, we present the results of experimental studies conducted on 142 modern cow (Bos taurus) and deer (Odocoileus virginianus) first phalanges to document the processing of phalanges, such as the required force and processing time to break them open, possible methods of breaking phalanges, and the resultant breakage and surface modification patterns. This comparative dataset and ethnographic data from contemporary hunter-gatherer groups indicate that broken phalanges in and of themselves cannot be taken as evidence of resource stress. The phalanges do not require substantial amount of processing time and marrow from the phalanges could have been preferred for its taste and soft texture during the period when resources were not scarce. This may explain the bone breakage pattern from an 8800 year old archaeological assemblage from Tangzigou in southwest China, where phalanges were intensively broken without any other evidence of resource stress.     

The relative effects of core surface morphology on flake shape and other attributes

It is long been thought that many flake attributes, including both size and shape, are largely due to the morphology of a core’s flaking surface, yet this has never been tested under strictly controlled conditions. Using molded glass cores with surface morphologies that highly resemble prehistoric ones, this experiment demonstrates that while core surface morphology does exhibit some influence on flake size and shape, a high degree of variation in flakes produced with the same core surface morphology shows that the effects of other independent variables, such as exterior platform angle and platform depth, have an even stronger effect. A major implication of these results is that current approaches to reconstruct prehistoric knapping strategies are overlooking significant sources of variation.