Carmen Lopez and Dr. Richard E. Terry, Plant and Animal Sciences
For many decades, scientists have been amazed by the magnificence of the Ancient Maya culture. Mayapan is a Postclassic (900-1500 A.D.) Maya city in the Yucatán Península that covers an area of 4 square km. It was the capital of the Postclassic Maya kingdom and it represents one of most significant sites for archaeologists. The tropical environment limits preservation of many of ancient structures and artifacts. Another important Maya city was found in the corn fields and pasture lands of Chunchucmil. The archaeological surveys of the area have yet to find the outside edge of the ancient city. Chunchucmil is located on high ground east of the coastal wetlands. Soil chemical analysis represents an alternative method of investigation of ancient household activities. Human activities that have taken place for considerable period of time have soil chemical signatures that can be examined as they are preserved in the soil. Relative concentrations of extractable phosphate and trace elements indicate specific ancient activities. High phosphorus is associated with food processing, consumption, and disposal. While high levels of heavy metals are related with mineral pigments and craft materials. The research evaluated in Yucatan has been possible with the ORCA scholarship which funded field work during the summer 2004.
Our objective was to use soil chemical analysis in the delineation of possible ancient activity on the surrounding of the structures P74 and Q10 taken from Mayapan (Fig 3.1, 3.2, 4.1, 4.2); and Sacbe 5 and Feasting area at Chunchucmil (Fig 1, 2). These activities are probable areas that correlate high signatures of phosphate concentrations with kitchens middens, gardens, feasting areas, animal pens and market place. Trace metals signatures correlate with workshops, shrines and craft activity areas.
Soil samples were collected from the surface (0- 6cm) soil in the enclosures in the structure P74 and Q10; and they were sampled on a 3-meter grid. Soil samples collected at Chunchucmil were collected on a 5-meter grid from both Sacbe 5 and the Feasting area, which are map in a East and Northing meter grid. The samples were then brought back to the soil laboratory at Brigham Young University for analysis for phosphorus and micronutrient levels. The samples were air-dried, ground to passed a 2-mm sieve in preparation for chemical analysis.
Soil samples were analyzed for extractable phosphorus with Mehlich II solution and concentrations were measured on a Hach DR/850 colorimeter. Trace metals (Cu, Fe, Hg, Mn, Zn, and Pb) were extracted using diethylenetriaminepentaacetic acid (DTPA) as a chelating agent and concentration were determined by ICP-AES spectrometry (inductively coupled plasma-atomic emission spectrometer). Spatial analyses of the concentrations were accomplished with Surfer software (Golden Software, Golden, CO).
In Sacbe 5, concentrations of extractable phosphorus are shown in Figure 1. Concentrations are relatively low in the center of the western portion of the Sacbe. Higher P concentrations on the edges indicate waste disposal. Phosphate levels in the eastern portion of the sacbe resulted from either domestic household or marketplace activities.
It is possible that households were established on the Sacbe in the late Classic just before abandonment of the city (ca. 850 AD). Waste middens are sources of high soil P levels. There was an ancient marketplace adjacent to the Sacbe and it is possible that marketplace activities such as, food exchange also took place at this location.
In Ritual Feasting area concentrations of extractable phosphorus in the floor of a ritual feasting area are shown in Figure 2. Relative differences in P concentration help us identify possible food preparation and consumption activity areas.
The result of the soil chemical analyses provided evidence of residential household or marketplace activities on a portion of Sacbe 5 at Chunchucmil. High concentrations of P in the floor of a plaza adjacent to the sacred ball court suggest ritual feasting activities associated with religious ceremonies. Enigmatic walled enclosures have been discovered at Mayapan. Soil phosphate and iron levels can neither prove nor disprove that the enclosures were used for domesticated animals. More intense samples will be required. This research has been extended with the proposal submitted for period of Sp-SS Archaeological project in Chunchucmil and Mayapan, in which the investigations are going to focus on the chemical analysis of biomarkers.