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Geochemical Analysis Of Ancient Activities At Two Plazas In Cobá, Mexico, Eric G. Coronel
Geochemical Analysis Of Ancient Activities At Two Plazas In Cobá, Mexico, Eric G. Coronel
Theses and Dissertations
Two plazas at Cobá, Mexico, may have been the place of market activity during the classic Maya period. The intense decomposition in the warm, moist soils of the Yucatan Peninsula precludes the identification of organic artifacts in archaeological contexts, but phosphorus and trace elements accumulation in soils may provide evidence of marketing activities. The spatial patterns of P and trace element concentrations were used to elucidate the types of ancient Maya activities that took place in those plazas. Phosphorus concentrations are highly correlated (p-value <0.01) with Fe, Mn, and Zn levels in both Plaza B and D. Although the soil geochemistry of Plaza B does not show a marketplace pattern in comparison with previous studies, the elemental concentrations and distributions within Plaza D join other lines of evidence to support the premise that marketplace activities took place at that location. Soil samples were analyzed using DTPA extraction, Mehlich II, Olsen, and Portable X-Ray Fluorescence (PXRF). Experiments were performed to study the suitability of PXRF for field studies. Aspects that were studied include granule size, soil moisture content, protective plastic films that could interfere with the X-Ray signal when placing the samples on top of the analyzer, and a comparison of certified soil standards to the PXRF elemental concentration readings. The results suggest that a field laboratory could be set up to air-dry and sieve soil samples to a minimum mesh size of #10 (> 2 mm).
Evaluating Nutrient Availability In Low Fertility Soils With Resin Capsules And Conventional Soil Tests, Mary Pletsch Jones
Evaluating Nutrient Availability In Low Fertility Soils With Resin Capsules And Conventional Soil Tests, Mary Pletsch Jones
Theses and Dissertations
Commonly used soil analysis and resin capsule procedures are used to assess nutrient status in fertile soils, but their validity in semi-arid ecosystems is unknown. Three studies were performed to assess resin capsule effectiveness in semi-arid ecosystems. An incubation study was completed in which loamy sand and sandy clay loam soils were treated with rates of N, P, Fe and Zn. Each soil treatment was implanted with a resin capsule and incubated for 60 or 120 days. Resin capsules reflected NH4-N and P fertilizer at low rates in the loamy sand. NO3-N reflected rates in both soils, but did not …
Geochemical Analysis Of Ancient Fremont Activity Areas At Wolf Village, Utah, Laura Morrison Pyper
Geochemical Analysis Of Ancient Fremont Activity Areas At Wolf Village, Utah, Laura Morrison Pyper
Theses and Dissertations
There is growing interest in the use of geochemical analyses for the evaluation of anthropogenically altered soils and other archaeological deposits. Areas of human habitation and activity tend to accumulate greater levels of soil phosphorus and trace metals. These elevated concentrations leave permanent signatures that can only be removed by erosion of the soil itself, and so phosphorus and trace metal mapping have become popular field procedures to identify areas of habitation and activity. Gridded soil samples were collected and soil phosphate and trace metal ions were extracted to identify these activity areas at the ancient Fremont site Wolf Village …