Excavation, conservation or both???

A common phrase you will hear is " all excavation is destructive" and this is true as removing any layers of earth accumulated throughout the many centuries and millennia is an irreversible act, but the level of destruction and it's worth varies from project to project. 

There are two broad reasons for excavation. The first is for research reasons. These are usually carried out by Universities and amateur organisations and are set up to answer specific questions. The reason for undertaking the project must outweigh the loss of the site that could otherwise be saved for future generations. By saved I don't necessarily mean saved so that future generations can dig it up, but saved for them to see and learn from in other ways. Imagine if we dug up Stonehenge and took it away in pieces to a museum, the original site and it's context in the landscape would be lost forever and future generations would never know it as we have.

Rescue excavations or rescue evaluations are the typical type these days and are exactly as they say on the tin. They are excavations that are set up to rescue as much archaeological information and artifacts as possible before the archaeological evidence is lost to building projects or maybe even coastal erosion. Watching briefs, ( an archaeologist actually watches whilst the bulldozers carry out their work to see if any archaeological evidence is unearthed), and Preservation in situ, ( where the archaeology is left where it is with minimal interference), are two of the main mitigation strategies used. This aspect of the subject goes into even greater detail including PPG16 which is a planning and policy guide issued by the government to help local planning departments concerning land development.

Every excavation must have questions that need answering, if it appears that these answers may not come from excavating then the site must be left alone. These questions that need answering, time constraints and of course money will all contribute to the decision making on where and how to dig.

Trenches and test pits are used if you need to dig down in order to understand the stratigraphy or layers of archaeological evidence. This method will give you an idea of the vertical profile of the area you are digging. Trenches are usually rectangular or "L" shaped of variable size depending on the site and test pits are usually square holes 1M². These are dug down until the questions are answered or until the natural bedrock is reached.

Area excavation is carried out if one of the questions you want answering is that you want to find out the layout of the site or its size and requires layers of a large area to be removed to reveal the archaeology below. Not all of the site is area excavated in one go as a site can be area excavated bit by bit over several seasons.

Both methods have their pros and cons and each has their own place on an excavation depending on the questions, time and money.

The field archaeologist will use several different tools in an excavation dig. If there is a top layer of turf then this will be taken off either with a spade or a mechanical digger, depending on circumstance, and put to one side out of the way. Depending on the site and the archaeology large tools will be used to go lower through the soil i.e. a spade or a mattock, or the archaeologist will go straight to the trowel. In Britain the professional standard is a WHS, (Spear and Jackson), 4" pointing trowel. The more worn the better it looks as this means you are obviously a well seasoned archaeologist.