K.A.S. Resistance Meter
The Society has purchased a Geoscan RM4 Resistance Meter for use by members.
The search for and discovery of archaeological sites can take many courses. Casual finds on the surface of a ploughed field, crop marks on an aerial photograph, building work of all kinds can all give clues to ancient occupation.
The move to encourage modern field archaeologists to adopt non-invasive techniques is amply demonstrated on the television programme Time Team. A whole variety of different instruments help the excavators to decide where to place their evaluation trenches to extract the maximum information with the least disturbance.
To give members of the society the opportunity of using one of these modem instruments on their own sites, or to take part in discovering new sites, a Geoscan RM4 resistance meter has been purchased.
Resistivity surveys measure the resistance of the ground at regular intervals. The resistance depends on a whole variety of factors. The depth of topsoil, the underlying nature of the bedrock and particularly the amount of moisture present. The principal variation that one is looking for is that normally building stone is drier than the surrounding soil and so gives a high resistance reading. Features such as pits and ditches dug into bedrock and then backfilled with soil will normally be wetter than the surrounding bedrock and therefore give a lower resistance.
With the advent of modern electronics and computers, surveys can now be carried out quite quickly, an area 20m by 20m at 1m spacings taking less than an hour.
The results can then be entered into a computer and using a software program called Geoplot can be processed and the information presented in a variety of different ways.
The K.A.S. Fieldwork Committee is organizing training sessions during the summer, normally on a Sunday, at a variety of locations throughout the county. If you as an individual member, or as part of a local group or society would like the opportunity to take part in resistivity surveys or have a site that you would like to survey, then please contact Ted Connell for further details.