Today I will look at the history of geophysics in archaeology and its development particularly in relation to the UK, although many other parts of the world have their own traditions in archaeologcial prospection.
See the end of the article for suggested reading! The suggested reading is also my bibliography.
The recorded history of Geophysics in Archaeology
It is tricky to mark the start of geofizz before World War 2. Pitt-Rivers arguably was the first person to record his geophysical efforts by using bowsing at Cranbourne Chase from the 1880's until the start of the 20th century. This involved slamming the flat end of a pick on the ground and listening to the change in tone. Some methods previously used include random and systematic shovel tests, trenching, soundings, probing and nose-sensitive dogs. Augering is any method that makes sound travel through the ground and returns a response. As sound travels in waves, the frequency of the waves changes depending on the solids that are within the ground and reflect off different surfaces and different depths at varying frequencies (which will change the pitch and volume of the returning sound) . It's very simple- you can use a mallet and record the sound (in decibels or with a more subjective opinion) and then simply record where you hit the ground. Easy! Trouble is that augering is not very precise, and it hasn't been used by any serious archaeologists since at least World War 2. However it's a good way of explaining simple physical principles.
These approaches have been inaccurate, potentially destructive and not statistically representative, not to mention expensive. As a result many sites remained deeply buried or otherwise invisible and unstudied. A few rudimentary geophysical surveys that attempted to map buried cultural remains were carried out in Europe and America in the 1920's and 1930's, using magnetic and resistance equipment that were developed for mining operations and often found geological anomalies rather than archaeological features but proved to be difficult to interpret.
|Malamphy's results of the survey at Williamsburg. The lines in the top left are the direction of the electrical current in the ground based on a the acoustic response from the equipment.|
The Start of Modern Archaeological Geophysics
Bevan, B.W. 2000. An Early Geophysical Survey at Williamsburg, USA. Archaeological Prospection 7. Pp.51-58