Question: Can LaRamie Soils Service help us identify terrains that have a high potential to yield in situ buried cultural materials?

Answer: Yes! By using geomorphic terrain analysis (Mcfaul 1990) and documentation of geologic relationships and pedologic (soil) horizons it is often possible to delimit areas with the potential to yield archaeological material. One example of such a project in which we used this procedure was a water pipeline in north central Colorado. Obviously, the archaeological potential of bedrock that comprised the local hogbacks was limited to surface finds and intrusive features, but there were also several Quaternary alluvial terraces in the region. In addition, several areas along the pipeline only had a thin covering (i.e., < 50 cm) of Holocene colluvial and eolian sediments. Though surface sites may be discovered in locales of thin sediment cover, the likelihood of in situ buried cultural materials is limited. By using terrain ranking we identify areas suitable for sub-surface testing and free areas of low archaeological potential for construction. Implementing geoachaeological reconnaissance can save clients money.

Question: We have found a specific buried sediment/soil unit that contains all of our cultural materials. It is unclear how extensive this unit is beneath the surface and it's not practical or desirable to excavate the whole site to determine the unit boundaries. Can LaRamie Soils Service help us determine the extent of this unit?

Answer: Yes! We have a trailer mounted Giddings Soil Exploration Rig that can be very helpful in assessing site extent. This machine takes 6.4 centimeter diameter cores and can collect samples from as deep as 12 meters below the surface. A 15.2 cm diameter core and a 25.4 cm auger are also available. One example of a project in which we used the coring machine for extensive sub-surface testing was along the U.S. 34 Highway expansion near Kersey, Colorado. This area is renown for its Paleoindian sites and megafauna (e.g. Wheat 1979). We cored an approximately 8.3 mile transect of the highway right-of-way, backhoe trenched likely locales, and developed a Holocene environmental chronology (McFaul 1991; Zier et. al 1994; McFaul et. al 1994, 1997). This environmental chronology was very helpful in assessing cultural/environmental relationships during the Holocene and helped speed highway construction.
Giddings coring rig 

Question: We have an archaeology site that does not contain datable materials. Can LaRamie Soils Service help us asses the site's age?

Answer: Yes! While radiocarbon or archaeological dating is preferable, sites can also be chronologically constrained by evaluating the age of the sediment/soil units with which they are associated. This is accomplished by correlation of geological and peological features of the site to known soil/sediment events in the region, glacial records, or soil/sediment units at other archaeology sites. Our experience with sedimentary processes, soil formation in the western U.S., and the expertise of a certified soil scientist make us uniquely qualified for such circumstances.

Question: Can LaRamie Soils Service help us determine if the cultural materials at our site are in situ?

Answer: This is one of the services we are most frequently asked to perform, and for good reason. Depending upon the setting of the site (e.g., floodplain, alluvial terrace, dune field, lake margins), a variety of geologic processes may have affected a site's integrity. During a flood, near channel sites are often eroded but sites further from the channel are gently buried by overbank silts and clays. Eolian deposition often buries cultural materials in situ, but eolian deflation may concentrate multiple components on a single surface. In addition, human treadage during and after site occupation can obscure the archaeological record. In the path of many debris slides, archaeology sites may be completely destroyed. However, at a site we investigated in western Wyoming the debris slide actually rode a cushion of air down the slope and buried the site in situ! Every geologic setting has its unique circumstances that determine the state of site preservation. Our 25+ combined years of geoachaeological experience allow us to determine the effects that geologic processes have had on sites.

Question: Can soil or sediment chemistry help us determine how different portions of a site may have been used?

Answer: Yes. Phosphate, organic matter, and calcium carbonate concentrations can reveal site utilization patterns. Our 250 m² facility in Laramie, Wyoming has a soil/sediment laboratory that can quantify a wide range of characteristics. Quantification also helps facilitate soil/sediment comparisons between different archaeology sites.
Laboratory Analyses 

Question: Can LaRamie Soils Service help us determine what the environment was like during a site's occupation?

Answer: Soil and sediment characteristics are a very useful tool in determining paleoenvironmental conditions. Some soil properties are associated with relatively moist soil forming conditions (e.g., thick humate-rich A horizons). Dry conditions, on the other hand, often result in slower A horizon development but encourage the accumulation of soil carbonates. Some of our soil/sediment investigations in the San Juan Basin of New Mexico have suggested that the environment at the beginning of the Holocene was more similar to the grasslands of north central Texas or central Kansas than the desert scrub that presently exists in the basin (Smith and McFaul, 1997). Sediments can also be useful in this regard. Multiple deposits of silts and clays on a floodplain suggest a relatively stable environment punctuated by occasional overbank flooding. Eolian sediments may represent dry conditions but, in some cases, they may also reflect an increase in sediment supply caused by increased precipitation. This type of information combined with the other environmental indicators that comprise the multi-disciplinary approach of modern archaeology (e.g., ethnobotanical studies) can be very useful for paleoenvironmental modeling.

Question: How can LaRamie Soils Service help our rockshelter or cave investigations?

Answer: The thin stratigraphy of cave and rockshelter sites is an ideal application for geoarchaeological investigation. By delineating geologic strata that may only be a few centimeters thick, the duration (s) of cultural occupation(s) can be precisely pinpointed. Detailed stratigraphic analysis also allows very accurate correlation between cultural materials that may be widely separated within the shelter. The type of sediments within a rockshelter stratum can be important environmental indicators. For example, rock spall deposits are considered to represent a cool, moist climate (Fryxell 1963). Chemical analyses can also assist in determining cultural occupation levels, environmental changes, and soil formation. Our work at Pendejo Cave, near Orogrande, New Mexico, helped establish that possible lithic materials dating >14,000 years BP within the cave were not alluvial in origin.

Question: Where are some examples of articles that LaRamie Soils Service has published?

Answer: Please look in the articles section of this site for references to our published articles. Copies of the journals that these articles appeared in should be available at most research libraries. If they are not, contact us.

References Cited

McFaul, Michael
    1990    Geoarchaeological potential of Souris River terrains, Renville County, North Dakota. Journal of the North
                 Dakota Archaeological Association, 4:17-42.

McFaul, Michael, Grant D. Smith, and Christian J. Zier
    1997     Geoarchaeological Interpretations Paleoindian Age Terrains: Kersey to Hardin, Colorado, edited by Robert
                   Brunswig. Manuscript submitted to University of Colorado Press.

McFaul, Michael, Karen Lynn Traugh, Grant D. Smith, and Christian J. Zier
    1994     Geoarchaeologic Analysis of South Platte River Terraces, Kersey Colorado.
                     Geoarchaeology 5(9):345-374.

McFaul, Michael, William R. Doering, and Christian J. Zier
    1991     Late Pleistocene-Early Holocene Soil-Sediment Relationships on the Kersey Terrace,
                  Northeastern Colorado. Current Research in the Pleistocene 8:117-119.

Smith, G.D., and M/ McFaul
    1997    Paleoenvironmental and geoarchaeologic implications of late Quaternary sediments and
                paleosols: north-central to southwestern San Juan basin, New Mexico.  Geomorphology 21 (1997) 107-138.

Wheat, J.B.
    1979     The Jurgens Site. Plains Anthropologist Memoir 15. Lincoln, NE.

Zier, C.J., Jepson, D. A., McFaul, M., and Doering, W.
    1993     Archaeology and Geomorphology of the Clovis-Age Klein Site Near Kersey, Colorado.
                Plains Anthropologist 38:203-210.