Texas Geoprobe Activity
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Archaeologists, environmentalists, and soil scientists are all interested in the same medium of research: dirt.
While some researchers are focused on environmental reconstruction others are interested in the relationships
between people and their surrounding landscapes, both in the present and in the past. One method of efficiently
testing soils and sediments for various research and business goals is through the acquisition of samples with a
coring device.
The Department of Anthropology at Florida State University owns a custom Geoprobe ¨ 540 RT/D direct push coring
system, wheel mounted for easy mobility and storage. It has been designed for rough terrain, and to fit
into tight spots. The corer is equipped with a hydraulic hammer (percussion rate of 30 Hz) for 620 ft. lbs. Torque,
and is powered by a Kubota diesel engine. Such systems are easily capable of coring to depths in excess of 30
meters, pushing at a standard consistent rate of 2 cm/second. Compaction is typically minimal, but is somewhat
greater in looser soils with high porosity. Two sampler sizes exist, 25mm and 55 mm. Individual liners are 124
mm long and the hole can be resampled to greater and greater depths with either a closed core system (solving
problems of slump and contamination) or with an open core system in stable soils by the use of extension rods.
For loose sediments internal core catchers also minimize sample lose.Ê
The corer is applicable to a wide variety of interests. At the Gault Site, north of Austin, Texas, soil cores
were taken in order to assess the local stratigraphy of a Paleoindian occupation overlain by a burned rock midden.
In Victoria, Texas, cores were taken from former oxbow lakes for pollen analysis at an archaeological site dating to
the Early Archaic. In Tennessee, cores were taken at low
water stream crossings that contained buried archaeological deposits.
Additionally, soil cores have been taken from the base of a Mississippian-period temple mound at Shiloh National
Military Park, in Shiloh, Tennessee. Cores were also taken from a peaty borrow pit, also at Shiloh, for
pollen studies. AT Shields Mound, near Jacksonville, Florida, cores were taken from a shell mound and a midden, to
determine construction methods and site stratigraphy and several cores reached 9 meters in depth. Additional work
has been done at a historic Spanish Mission (Mission San Luis, Tallahassee, Florida) and coastal
archaeological sites (Okaloosa County, Florida) and remnant shell middens in Volusia County, Florida.
Because the sample liners are clear PVC, soil strata, texture, and color can normally be evaluated immediately. The
cores are sealed for later detailed analysis, like phytolith, pollen, particle size, chemistry, texture, etc.
Other liners, including brass and stainless steel can also be used.Ê
The Department of Anthropology at Florida State University offer the following services: sample preparation, grain
size, texture, color, pH, trace element, and phosphate. Other testing regimes can be customized for
individual projects.
'Geoprobes are great for
extracting cores for pollen analysis as we did in
Texas to get this series of samples from some very sand sediments. View PDF
Research report using Doran's Geoprobe investigations at Buckeye Knoll,
summer of 2001
Albert, Bruce M.
2002 Holocene environmental change and changing conditions for human subsistence as
inferred from Geo_botanical data from two cores in the Lower Guadalupe River Valley
by the Buckeye Knoll site (41VT98) near Victoria, Texas. Draft report prepared for
Coastal Environments, Corpus Christi, Texas and the U.S. Army Corps of Engineers,
Galveston District.
