gibraltar caves project 2003

methodology

Excavation Techniques & Methodology

The reasons for embarking on excavation have changed radically over the last 50 years. In the 1930s the research interests of the excavator, or the curiosity of amateurs dictated excavations. These attitudes persisted throughout the period of the Second World War up until the 1950s. Although there had been efforts to co-ordinate fieldwork and excavation (notably by the Council for British Archaeology in the UK) and archaeology was becoming a far more respectable subject in universities, there was little real organisation. Dr. Waechter’s excavations in Gibraltar reflect this. To be fair to him though, he was a professional and he probably felt he was doing the best job he was able to at the time.

The average archaeologist today would suggest that the single most important advance of this century would be archaeology’s development as a science and all the scientific techniques that have since been adapted to aid its work. It can be said that this as all the more true for prehistoric archaeology. Probably every generation of archaeologists that make a deliberate effort to improve on the advances of the previous generation, in discovery, analysis and interpretation, see themselves as more scientific than their ancestors. The result of this is that we often look at the work of these past archaeologists in a critical manner and do not give them the credit they are due, perhaps in a way we put modern day expectations on the past.

Throughout the twentieth century there have been significant developments in techniques, methods and attitudes towards archaeological excavation. In the first place  the need for planning and method in all archaeological work has been recognised. There is a conscious effort to minutely record the position of objects in three dimensions. Ideally, results of an excavation should be recorded in such detail that anyone could go back to the data sets and be able to reconstruct the site in their mind. This would enable any further questions asked of the site to be answered, and if need be the whole site can be reinterpreted on the evidence collected and recorded.

 

Gorham's  under excavation in the 1950s. Large sections were left exposed and unsupported

Gorham's in the year 2000. Note the smaller stepped sections supported by sandbags.

Methodology
 

The Cave floor has been split up into a grid of 1m squares. As the cave floor is uneven and also to avoid people tripping over them, the grid lines have been attached to the cave wall. A great deal of care was necessary when mounting the grid to ensure that it was completely horizontal. Any errors would result in incorrect measurements being taken during excavation. Once the grid was in place each square was given a coordinate number. For the duration of the excavation, however many years this may take, each square will keep this coordinate number.

Measuring location of finds	A pulley system transports sediment to the beach for sieving
Excavation in progress

As each square is excavated every find that is made is measured and drawn to scale on a site plan. Finds materials are colour coded for ease of reference, for example yellow= bone, green = flint and red= stones. An item description Is entered on a finds sheet, the item is given a finds number and its location is recorded in three dimensions- its co-ordinates within the grid and its height/ depth in the level. This is done using a dumpy level.

Once its location has been recorded the find is removed from its context or layer and is bagged together with a finds label stating its excavation date, location co-ordinates and identification number. The object is then taken to the finds laboratory at the end of the day for processing.

Recording sheets used to record finds and their locations

All sediment that is excavated from the caves is bagged and sent out of the cave via a pulley system for sieving. The sediment is dry sieved first to remove excess sand and it is then wet sieved. This entails passing water over the material. This serves to wash to items and helps people picking through the sieves to identify and pick out any finds missed by the excavators. These are usually small bones and tiny chips and flakes or ‘debitage’ from the stone tool making process. These tiny fragments can sometimes be ‘refitted’ by archaeologists to reform the original stone a tool was knapped from. This is useful in telling us whether the inhabitants of the cave were bringing unprepared raw materials to the cave or whether they had already been prepared elsewhere. Any finds that are made during the sieving process are then themselves bagged and labelled with a note of the square the item came from being made.

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