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Dates of Occupation Marker
Photographer: William J. Toman
Taken: September 4, 2010
Caption: Dates of Occupation Marker
Additional Description: Archaeologists use several methods to determine age. One approach is called relative dating. One method of relative dating is based on the principle that things lower in the ground are generally older than those higher in the ground - you can thus tell that one group preceded another. Another relative technique is based on the principle that if dated distinctive artifacts from a culture are found elsewhere, those artifacts likely date to the same period.

In 1949, radiocarbon dating was developed, and could, for the first time, determine a specific age range in calendar years from charred pieces of organic material. At Aztalan, this technique helped more reliably determine the site's antiquity. Aztalan may have been occupied as early as AD 600 and as late as AD 1830; however, most dates occur between AD 1100 and 1300, and most artifact types are contemporary with this period, so we can be reasonably sure that Aztalan was occupied most intensively during this time. The very early dates indicate an occupation not associated with the stockade and mounds. The late dates may reflect a brief historic occupation.

[The chart, entitled "Aztalan Radiocarbon Dates" and with a caption stating "Dates of Occupation: Chart showing the range of radiocarbon dates that have been analyzed at Aztalan," has "Calendric Dates (mean values)" on the vertical axis, with dates ranging from AD 600 to 1800, and "Samples arranged chronologically" on the horizontal axis," and shows most samples fall between AD 1000 and 1200.]
Submitted: October 30, 2010, by William J. Toman of Green Lake, Wisconsin.
Database Locator Identification Number: p134077
File Size: 3.590 Megabytes

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