There are several stages in the archeological process. They include excavation, surveying, and analysis. These stages often overlap, but all require archeologists to painstakingly document their activities. Excavation is ordinarily the most labor intensive part of the process, typically requiring many site workers working at once over small defined areas of a site.
The care taken during the excavation process is paramount, as the attention paid to detail can directly correlate to the validity of discoveries and cultural theories. A comprehensive log must be kept by each site worker because:
- The process of excavating essentially results in the demolition of the site. Therefore, the only remaining records — once the archeologist has dug — are the archeologist’s detailed notes, photos, and recovered artifacts. Unfortunately, during the Tutankhamen excavation some painted wall scenes were destroyed so that the burial chamber artifacts could be removed. These wall scenes can never be recovered.
- In order to analyze the recovered artifacts, an archeologist must be able to study the context in which the items were found. Precise data can later facilitate the construction of an accurate site model; knowing the location of an object in relation to other objects allows us to imagine how that object might have been used. In addition, using knowledge of the number of soil layers and kinds of sedimentary deposits, a relative date of the object can be determined.
For the above reasons, laying a grid is essential for any archeological dig. The grid size can vary, but the best approach is to examine the entire site and then mark off grids in small enough units to allow for a controlled excavation. Once a grid is in place field workers can begin the process of stratigraphic excavation, which is the keeping of carefully kept records that enable someone off-site to construct a three dimensional model of the site. Doing so requires working in small areas, keeping exact measurements, and always working vertically. Archeologists use the term, "locus," as the elemental recording unit.
Field excavation requires a high energy level and supreme focus; workers must remain alert at all times. Immediate and personal observations are essential to successful digging, as is the attempt to contextualize all evidence found. In addition, although excavation procedures are few in number, they require experience and field work with soil to learn which techniques to apply, and when.
Because of erosion and drifting over time, soil layers do not always remain constant. Despite variation in levels, archaeologists strive to remove soil evenly, working in small increments to avoid oversights. They analyze the soil as they dig, noticing how the layers and deposits of the soil are situated and how they relate to one another. They sample the soil using various tools, and consult experts from other disciplines who are taking part in the dig. This careful examination is essential in dating any artifacts found.
In archaeology, the term "dating" refers to the act of determining an object's age. Typically, there are two types of dating techniques used by archeologists: absolute and relative. Absolute dating employs scientific tests, such as radiocarbon, to determine an artifact's calendar age. Relative dating, such as stratigraphy, is used to place an artifact in a sequence in time (i.e., whether a particular object or event is older or younger than another object).
Useful tools are those that aid the archaeologist in determining the exact contents of the soil and its environment. These archeological tools may be familiar to the layman, but in the field, they have very specific purposes.
- Measuring tapes, string, and survey flags outline an excavation area, providing borders to guide site workers
- Surveying instruments and plumb bobs allow for precise location recording.
- Large Pick In the hands of a skilled worker, this tool loosens large areas and readies the soil for closer inspection. The area in which a field worker operates is compact and tightly controlled. A worker adept at using the large pick will know how to use it properly without exhausting himself. Always work from one end to the other, and remember that the goal is to reveal the layering of the soil, not to simply remove it. Use of the large pick should stop at substantial soil changes or upon evidence of an installation.
- Hand pick The most versatile and often used, the hand pick is ideal for vertical excavations. Never use a too-heavy tool, making sure that it has a broadly curved head, with a haft that allows for concise manipulation. Use the hand pick in conjunction with the trowel.
- Trowel To increase exact control, the trowel is indispensable. When evidence emerges, use your tools in a delicate manner and in the proper fashion. Like all tools, the trowel should feel comfortable, being neither too light nor too heavy. Best for concentrated areas, trowels are also handy for large, shallow strafing to remove accumulated soil that has been inspected.
- Hoe Use the hoe for soil removal along with a small basket for transporting. Always glean the soil for evidence before depositing it off-site.
- Sledge Used to break up large boulders. Perform this task off-site, to minimize creating more debris. Choosing a comfortable weight is important, and the field worker wielding the sledge should exercise the same care as when handling the large pick.
- Brooms and Brushes These tools are used for the gentle cleaning often needed at sites. They are essential at the end of the workday, since you should clean the site in preparation for the next day's dig.
- Ladders and Hoists Always be careful whenever using a ladder, making sure the rungs are intact and anchoring the ladder properly. Ladders should be lightweight and easily transported. The hoist, used to remove material from deep excavations, should be comprised of a pulley, rope, and sufficient counterweights.
- Sieve For screening the soil. This is an excavator's "third arm."
- Household Items Digging often requires the on-site adapting of small implements, such as toothbrushes, razor blades, spoons, etc. Use spray bottles of water and ball syringes as a shot of air to clean minute areas.
- Baskets, Boxes, etc. The worker must have appropriate ways to transport any evidence.
- Work gloves and knee pads.
The excavation phase of archeology is only the beginning. After many days spent digging, archaeologists spend significant time in the lab examining the artifacts and documenting their discoveries. With meticulous excavation techniques and detailed logging, these discoveries can reveal the past.