Fieldwork at the Koster Site in Illinois occurred in the 1970's.
The Koster Site was the location of settlement for a series of human groups over a period of 10,000 years of occupation.
There are at least 26 separate living horizons present.
Major villages existed around 3300, 5000, and 6600 B.C.
The finds from the site include millions of artifacts and other remains.
Research at Koster was a part of the activities of the Center for American Archaeology (CAA).
The Center was established in the area in 1953.
The CAA's mission is to discover and disseminate the unwritten story of earlier Americans' lifeways, accomplishments, and changing natural environment.
Fieldwork is of the utmost importance in archaeology.
Fieldwork is the essential means for obtaining the basic information used to understand the past.
Assembling the time, energy, money, permission, equipment, and crew necessary for a field project is a major undertaking.
Survey and excavation are the primary discovery techniques of field archaeology.
The Discovery of Archaeological Sites
Finding sites requires a combination of methods that includes research in libraries, fieldwork, and communication with amateur archaeologists and local people.
Archaeological materials are most commonly discovered by accident.
Prior to beginning fieldwork, archaeologists check the relevant written material on the time period and place of interest.
Local Historical Society, or other archaeological institutions are consulted.
Archaeological Survey
There are two kinds of surveying that archaeologists do.
Archaeologists do surveying by field walking or reconnaissance to look for artifacts and sites on the landscape.
They also do instrumental surveying to make maps and plans of the places and areas of interest.
A complete reconnaissance of the entire area under investigation is not always possible.
A representative area may be surveyed.
Landowners in the selected area should be contacted.
Archaeological reconnaissance, or field survey, involves systematic field walking.
When an artifact is found, the object is counted, sometimes put in a bag and the location of the find is recorded.
Archaeological Thinking: The Reese River Valley, Nevada
David Hurst Thomas engaged in research in the Great Basin.
The Great Basin is between the Rockies and the Sierra Nevada.
Limited rainfall accumulates in the basins as lakes and playas.
The landscape is varied and rather sparse.
The Shoshoneans lived in the region.
They engaged in a hunter-gatherer lifestyle, moving frequently.
There lifestyle was largely destroyed by the European settlement of the West, beginning in the 1850s.
Thomas evaluated proposals by anthropologist Julian Steward.
Steward argued that the limitations of the natural environment determined and limited the population, settlement pattern, and economy of the Shoshonean peoples.
Thomas did an archaeological study in the Reese River Valley of Nevada, in the western part of the Great Basin.
Thomas used random sampling to survey the area over a period of 4 months.
The entire survey took four months and recorded about 80,000 stone artifacts of which 2500 were intentionally shaped tools.
Two general areas of base camp settlement were distinguished within the study region.
From the information obtained, Thomas was able to define a dual-residence settlement pattern.
The results from the survey confirmed the pattern that Steward had suggested.
Archaeological Excavation
Excavation is the technique that archaeologists use to uncover buried remains from the past.
Buried materials usually are more abundant and better preserved than those found on the surface.
Excavation often is essential to obtain more information.
Excavations are conducted to answer specific questions that the archaeologist would like to resolve.
Selecting Sites for Excavation
The choice of a site for excavation is determined by several factors.
The potential threat to the archaeological remains is typically considered.
The level of preservation or the possibility that new information will be obtained are also considerations.
It is important to know as much as possible about a site prior to full scale excavation in order to choose the best strategy for the project.
Test Pits
Preliminary examination of a site usually involves making a few small excavations to preview the site.
Test excavations can be small, vertical test pits, or a series of one or more trenches across the site.
Shovel testing is another technique.
The size and number of test pits to be excavated depends on the kind of information being sought.
Vertical Excavations
Vertical excavation takes the form of squares or rectangles carefully positioned across a site to expose stratigraphy and artifact contents.
The stratigraphy, or layers of natural sediments and human deposits, reveals how the site was formed and accumulated.
The bottom layer is deposited first as the oldest layer in the sequence.
The thickness of a layer is determined by the natural and human activities involved in the deposition of the materials.
Horizontal or Area Excavations
Horizontal or area excavations expose large open areas of ground, one layer at a time.
Area excavations are intended to recover information on site arrangement and structures.
Several different kinds of burials can be found.
When the site stratigraphy is relatively simple it is sometimes possible to separate the remains from each stage of occupation.
A variety of samples are taken from different layers in the walls of the excavation and from the occupation floor.
Soil samples are taken to help define and characterize the deposits at the site.
Pollen samples are sometimes taken to assist in defining the vegetation in and around the site.
Samples of charcoal and bone are taken for radiocarbon dating at most sites.
Several things happen after a dig.
The excavation has to be filled up.
Records, artifacts, and samples must be shipped back to the home laboratory.
More detailed analyses of the recovered materials and the writing of excavation reports occur.
Final results of the investigations are made available to the public and to professional archaeologists.
Screening and Flotation
The excavated soils are usually sifted through screens and/or washed with water to find even the smallest objects, fragments of bone, and plant remains.
Dry sieving works reasonably well in loose.
Water screening is recommended in most situations to insure more complete recovery of small items.
Mesh size of the screen is variable from place to place and from archaeologist to archaeologist.
Flotation has become a standard technique at sites where carbonized plant remains are preserved.
Flotation involves the use of tubs of water for separating sediment and artifacts from the plant remains.
Normal water sieving tends to destroy fragile materials such as plant remains.
Example: The Great Hall at Lejre
Denmark has a long list of kings and queens that starts with Gorm around 935 AD, during the Viking period.
There are legends of earlier kings.
These stories name the place called Gammel Lejre as a once powerful center.
New excavations near the town of Gammel Lejre, outside of Copenhagen, have revealed evidence for substantial wealth and power at a date earlier than the Vikings.
Postholes and features revealed an enormous wooden structure which was probably the largest building in northern Europe at the time.
A plan of the postholes that were excavated reveals a ninth-century Viking Age hall built over a less well-preserved, earlier building.
Underwater Archaeology
An increasingly important part of archaeology is being done under the sea.
Underwater archaeology became famous with the recovery of Bronze Age shipwrecks in the Mediterranean several decades ago.
It still largely focused on shipwrecks from around the world.
Survey and excavation conditions are more difficult and costs are substantially greater.
Exceptional preservation of organic materials often makes the effort worthwhile.
The Tools of Fieldwork
Archaeological projects in the field require tools and information to operate effectively.
These tools include maps and positioning information to locate sites and artifacts exactly in geographic space.
Maps are one of the most important tools of fieldwork.
Archaeologists today try to peer into earth before they dig using a variety of remote sensing techniques and technologies.
Maps And Grids
Accurate mapping of layers and artifacts is the key to the proper recording of information on an archaeological project.
Maps and plans are made by instrumental surveying, a technique used by land surveyors and cartographers.
A grid is marked out across the surface of an area prior to reconnaissance or excavation to be used for all horizontal measurements.
Location of the site and the site grid in relation to global latitude, longitude, and elevation above sea level must be determined.
Contour Maps
A contour map of an area shows the topography, the three-dimensional surface of the place.
The elevation of the ground is measured in feet or meters above sea level or a known fixed point, or datum.
A grid is laid out and measurements of the elevation of the ground are taken at regular intervals across the grid.
Mapping projects are greatly simplified today with the use of satellites, computers, and lasers.
The Total Station
A total station measures both horizontal and vertical directions simultaneously.
Total stations use an infrared laser to calculate distance and three-dimensional angles to determine the precise location of the target in terms of grid coordinates and elevation.
The total station can be used to produce contour maps and to located artifacts and architecture precisely in three dimensions.
Science in Archaeology: Global Positioning System (GPS)
A series of satellites broadcasts information for determining exact locations on the earth's surface.
Portable GPS equipment can determine precise locations within a few centimeters.
The use of GPS is now standard in archaeology.
The combination of GPS and Geographic Information Systems provides a powerful set of tools for archaeology.
Geographic Information Systems
Geographic Information Systems (GIS) are a potent means for recording, analyzing and presenting geographic or spatial information in archaeology.
GIS resulted from the marriage of computers and cartography.
A GIS representation of an archaeological project would include a set of maps or plans of the area of interest and a series of locations in that area.
GIS can be used to project where archaeological remains might be expected.
This use is popular with planners because it is cheaper than fieldwork.
The technique is called "predictive modeling".
Soil Sampling
Once buried sites have been located, other kinds of fieldwork can begin to learn more about them.
A number of corings and/or test pits often are made, following a regular pattern over the surface of the site.
Soil samples should be collected from all parts of the site and at different depths.
Physical and chemical analysis of soil samples may provide information.
Phosphate analysis of the sediments from a site may reveal traces of human activities.
Phosphate testing may supplement surface surveys.
Other objects in the soil are also informative.
Various materials are often found in soil samples.
Such items provide information on the formation of the layers, the local environment, and the nature of past human activities.
Remote Sensing
Remote sensing involves instrumental techniques for peering onto or into the ground without digging.
These prospecting techniques detect differences in the vegetation or subsoil and the presence of prehistoric features and disturbances.
Several remote sensing methods are available.
Remote Sensing from Above
Air photographs also can provide information on the location of archaeological sites.
When prehistoric structures were originally abandoned, the depressions often filled with rich topsoil.
Different soil conditions might result in a distinctive pattern showing the outlines of houses or whole villages.
Satellite photography and other technologies can also be used.
A variety of instruments can scan the electromagnetic spectrum emitted from the earth's surface.
Radar instruments bounce energy beams off the ground and read the returning signal.
Example: Chaco Roads
In 1050 AD Chaco Canyon, Arizona, had a population of some 5500 people living in large multi-room apartment complexes known as pueblos.
Town and villages were connected to each other and the outside world by more than 600 km of roads.
Chaco roads were broad, usually 8-10 m in width.
The roads were not well known until satellite photography of the area became available.
The roads are mysterious.
The roadways appear to be much wider and more substantial than needed for the foot traffic in the region.
They are also discontinuous, often composed of a number of short segments.
Remote Sensing on the Ground
Several different kinds of detectors can be used at archaeological sites to look for buried artifacts and features.
Metal detectors register the presence of metal objects on the surface or buried in the soil.
Magnetometers are a more sophisticated form of detector and record variations in magnetic fields.
A resistivity meter can be used to measure soil conductivity and map differences in soils that may be due to the presence of buried disturbances such as fireplaces, burials, or other structures.
Ground penetrating radar (also known as georadar) sends electromagnetic waves into the ground.
Science in Archaeology: Georadar at Petra
Petra is an ancient city in Jordan.
Petra was founded some 600 years before Christ.
Its defensive and hidden situation protected the city until the Romans finally conquered it around A.D. 100.
The city was abandoned some time after A.D. 500.
These canyon floors have been buried in sediment from episodic rainstorms and flash floods.
A georadar survey of some of open, flat areas was undertaken.
In the Field
There are a variety of roles to be filled on a survey or excavation, depending on where and how big the project.
The project director is usually the person who plans the work, organizes the project, raises the funding, and makes arrangements for permission, equipment and crew.
Bigger projects may have one or more specialists present as well.
The field crew consists of the students, volunteers, and laborers that provide the work force for survey or excavation.
Extensive field equipment is typically required.
The Project Director
Directing a field survey or excavation requires a variety of skills.
The director must plan a field season, raise money, and supervise the crew.
Excavations require reams of notes, drawings, and other paper work.
The director must keep an excavation log or diary.
The investigator must monitor progress in the field laboratory as well.
The Field Crew
This crew is the group of people involved in the actual digging process, unearthing the sites and artifacts.
Members of the field crew on a CRM project are typically paid employees.
Field crews on academic projects can include professional archaeologists, students, and other interested individuals.
Archaeologists may hire local individuals to do necessary construction, earth moving and some detailed excavation.
The Field Experience
Fieldwork can require a few days, weeks, or months.
Surveys or excavations are typically required.
Fieldwork can be an extraordinary learning experience.
Fieldwork Opportunities
Every archaeologist should participate in fieldwork.
Not everyone enjoys the field experience.
Many graduate students are involved in fieldwork over the summers of their studies.
Probably the best place to begin in archaeology is to participate in a field school.
Universities around the U.S, Canada, and Britain conduct training projects of students known as field schools.
Field schools are conducted as part of larger projects or specifically for the training of students.
Field schools expose students to a variety of tools, methods, and techniques and usually provide an important first exposure to outdoor archaeology.
Equipment
Most excavations are organized so that each excavator has a small kit of tools in addition to the common excavation equipment.
A wide range of equipment is generally required for archaeology projects.
