Types of Surveys
A survey is an archaeological tool used for three purposes. Ideally, a good survey will help an archaeologist locate a site or sites, define the limits and type(s) of the site(s), and also allow the archaeologist a good opportunity to sample the site. There are many different types of survey and many different methods of survey. Below are listed the different types of surveys, and what they entail. On the page archsurveys2.html will be listed the different methods used in surveying. Please use that page as a suppliment to this one and vice versa.
1) documents and interviews: an archaeologist can learn from the people in the area he/she wishes to learn about. Much of the past is still alive in folklore, although this needs to be carefully sifted to determine which parts may be relied on. More useful to most archaeologists are "sitings" made by local people. By interviewing the local populace, and archaeologist can determine, based on what people have seen and/or collected, where high concentrations of surface collections are located. This in turn can help the archaeologist determine where to dig (1st goal), how big the site might be and what type (2nd goal), and will provide a rough sample of what the site may have to offer (3rd goal).
2) Aerial reconnasaince: people are messy critters. Due to the nature of organic material and human by-products, it is often possible to spot regions inhabited or formerly inhabited by people based on differences in ground texture or elevation. Much of this can only be seen from a great distance, such as possible through aerial observation. By being aloft in an aeroplane (or more commonly by looking at pictures generated from an aeroplane), an archaeologist is better able to locate soilmarks, crop marks, and shadows that are nearly invisible at or near ground level. This method is excellent for fulfilling goals one and two, although somewhat short on goal number three.
3) surface survey/ walkover: A walkover is exactly what it's name implies it is: a simple "walking over" of a prospective site. It involves looking for artifacts on the ground from the ground. It is quick and cheap, obvious advantages in a cost-conscious world. Unfortunately however, what is on the surface does not always reflect what is beneath the soil, so this method may miss large areas. However, overall it does have it's uses, and satisfies goals one and three quite well well leaving two perhaps vague (depending on walking patterns and comprehensivity).
4) remote reconnasaince: looking for a site without useing eyes. An example is electrical resistivity. This is a very expensive method of looking underground. By inserting two metal poles into the ground and running a current through the ground between them, the resistivity of the medium they poles are immersed on can be measured. Objects such as stone walls or building foundations have a higher resistivity than do underground pools of water or regular dirt, and this fact can be quite useful. However, this is rather expensive (as if ground-penetrating radar, another form of remote reconnassaince), and is generally used only on already discovered sites. The cost of this technique makes it poorly suited to goal number one. Goal numbers two and three, however, are filled admirably.
5) sub surface shovel testing/quarrying: this is the most common tool used in the Northeast United States. Workers generally dig small holes (50 cm x 50 cm or so, depending on preference) in the ground. This reveals stratigraphy, possibly postholes, allows a cheap and easy search for artifacts, and leaves ground for the next generation without destroying the site. It is compatible with goals number one and three, but has some trouble (depending again on comprehensivity) with goal number two.
6) targeting environmental resources: this is a very general method that is used very frequently. Most historic and presumably prehistoric people would not, given the choice, settle preferrentially in a "bad" environment rather than a "good" environment. By determining what is a good and what is a bad environment, an archaeologist is able to determine where it is likely that sites will be found. This method works well towards none of the goals, but can help narrow down a region before using another method.