Yet more 1955

Today was very warm and sunny with white poofy clouds and a gentle breeze. Ideal for sitting in the garden with a large jug of Pimms and a good novel. We, however, were out on site pushing a mag or GPR, or prodding the ground with the resistance meter. It was, however, worth it!  Many thanks to everyone who turned out on such a hot and sunny day.

The mag survey went well with Jim, Dave and Ellen completing eight whole squares and re-doing part of one where the sensors had frozen on Thursday.  This image shows the whole survey of the town, so far.

The overall magnetometer survey at the end of day 22.

The overall magnetometer survey at the end of day 22.

There are times when the “theatre field” feels so huge that we will never finish.  The mag, however, is getting there.  Another day or two and we should complete that swathe, and then we can start working our way north once more until we have finished the whole of that field.

Looking at the area that was surveyed today, the most striking feature is the infamous 1955 ditch.

Detail showing the area surveyed on day 22.

Detail showing the area surveyed on day 22.

The ditch shows clearly as the broad black line with white edges running across the plot.  At right angles to the ditch is a road with buildings (shown as low-magnetic white lines).  Outside the ditch to the south-west are several smaller ditches (shown as thinner black lines) as well as some probable pits (the black blobs).  As we saw in the park, the 1955 ditch seems to mark a clear divide in the town between the busy built-up area inside it and the quieter area outside it, despite the fact that the ditch is supposed to go out of use 250 years before the “end” of the town.

The earth resistance survey continued eastwards and picked-up the building seen in the GPR data last year,  Remember than in our resistance plots the walls show as darker, high resistance, lines whereas in the mag they show as white lines.

The earth resistance results after day 4.

The earth resistance results after day 4.

It is interesting to compare the resistance results to the GPR data of the same area.

The resistance results overlain on the GPR results.

The resistance results overlain on the GPR results.

The same area as the previous image showing just the GPR results.

The same area as the previous image showing just the GPR results.

Last but not least the GPR results.  The team completed another 80x40m block.  There is surprisingly little that is very obvious in the time slices, but the line of pits does show as an area of low reflections (white) and there are hints of robbed walls.  Most fascinating, however, is a small apsidal building about 15m long and 5.5m wide.  Here are the fourth and fifth time-slices.

The fourth time slice (15.5 to 18.5 ns) showing the apsidal building.

The fourth time slice (15.5 to 18.5 ns) showing the apsidal building.

The fifth time-slice (15.5 to 18.5 ns).

The fifth time-slice (15.5 to 18.5 ns).

Tomorrow will see us out in the field for the last day of the first week.  Monday and Tuesday is our “weekend”.

 

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