Soils and Archaeology

John E. Foss, Yul Roh, and Debra Phillips University of Tennessee and Oak Ridge National Laboratory

Outline

1. Introduction

   1. Definition of archaeology: Science that has at its goal “the excavation, examination, and interpretation of the material record of man’s past.”
       

   2. Location and type of local archaeological sites. Contact your local college or university for help in locating sites.
       

   3. Definition of soil: Soils are natural bodies on the earth surface with characteristics resulting from past and present weathering processes regulated by the factors of soil formation (climate, vegetation, geology, topography, and time)
       

   4. How soil science, especially soil genesis and classification can aid in the study of archaeology? Study the 9 major pedologic contributions to the interpretation of archaeological sites.
       

2. Field Studies

   1. Geology is a major factor in the formation of soils in a region. Note that on the Karak Plateau limestone and occasionally basalt are the bedrock types and loess (wind-blown silt) is the surface geologic sediment (Figures 2, 5, 6). What types of geologic materials are present in your area? What types of soils are present? Note: check in your local county soil survey published by USDA, U.S. Government Printing and should be available in your local library or USDA office.
       

   2. Soil morphology is the key to understanding the archaeological history of a site. The “great paints of the earth” are organic matter and iron compounds, and the intensity of these paints in soil is the result of weathering processes. Note the colors (or paints) of the soil profiles in Figure 9. Why is organic matter of soils usually higher in areas of more rainfall on the Karak Plateau? This is related to the amount of vegetation that can exist with the attendant rainfall.
       

   3. What is the intensity of paints in soils of your area? Is there a difference in the intensity of the various paints with depth in a soil profile. Observe a local roadside bank or recent excavation.
       

3. Laboratory Studies

   1. Laboratory studies supplement the field identification and classification of
      soils at archaeological sites. Why is the particle size analysis of samples so valuable for interpretation of sites?
       

   2. In Figure 10, what is the explanation of the dark colors at the bottom of
      the soil profile? How long would it take to add that much organic matter to the soil profile in this desert environment? The dark colors are the result of organic accumulation during the time that this was the active surface. It would probably take at least 200-500 years to accumulate this amount of organic matter. If rainfall levels were higher than present, the amount of time could be less.
       

   3. Why is soil phosphorous such an important element in evaluating the intensity of habitation of an archaeological site? Consider the source of phosphorous in human activity. What other elements may accumulate in soils as a result of human activity? Consider this from ancient times and then the present time.
       

   4. What are the major minerals on the earth’s crust? What are the major minerals in most soils? Are dominant minerals occurring in soils of arid regions different from those of humid regions? Compare minerals such as halite, gypsum, calcite, feldspar, and quartz.