Around the bend

We are within four grid squares of completing the “Theatre Field.” The sheer size of the field doesn’t really come across in the images. From the northernmost point to the southernmost it is 855m and it is 600m from east to west, enclosing an area of 27ha. That is about 38 soccer pitches in area!

The survey of the Theatre Field after day 28.

The survey of the Theatre Field after day 28.

But enough of all this nonsense about soccer pitches, I hear you cry, what about “the sinuous ditch”?  Well, here it is…

The course of "the sinuous ditch" after day 28.

The course of “the sinuous ditch” after day 28.

Yup, the ditch is now heading north again.  On a flat image, this looks really odd but when one is in the field it seems pretty clear that it is following the contour lines.  Perhaps we can still consider the ditch an aqueduct?  Here is a detail:

Detail of the area at the end of the sinuous ditch.

Detail of the area at the end of the sinuous ditch.

The section of the ditch surveyed today seems very broad, and gets a bit fuzzy near the big irregular feature shown in stronger black and white.  My guess is that the irregular feature is a later quarry pit — very common in the Hertfordshire countryside — and this may have partly destroyed the ditch.  Who knew that the last four squares might provide the answer to this mystery feature!  There are also quite a few weaker and more indistinct ditches in this area, along with quite a few pits.

The GPR crew worked their way steadily eastwards along the northern edge of the Theatre Field.  They have covered an amazing area too.  Remember that (a) they have to walk four times as far to cover the same area as the magnetometer and (b) their cart is dragging a plastic tray along the ground.  In longer grass it is quite a difficult task.  Despite this, look what they have now covered.

The total area covered by the GPR.

The total area covered by the GPR.

This image is a bit of a mish-mash of different time slices but it conveys the main message… look what we have covered!

Here is a detail of the last two days area:

Detail of the area covered during day 27 and 28 of the survey. Fourth time slice (15.5 to 18.5ns).

Detail of the area covered during day 27 and 28 of the survey. Fourth time slice (15.5 to 18.5ns).

The surviving wall foundations are easy to spot: the black lines looking like buildings!  We are, however, also seeing the outlines of building foundations in white where the stone has all been removed just leaving robber trenches.

The GPR data is just being fairly crudely processed here as it takes much longer to do than mag or resistance data.  At some point I will need to process it all in much more detail and much more consistently.  It does, however, give us an excellent comparison with the mag and res data even with this basic level of processing.

Tomorrow and Tuesday are our “weekend”.  We all deserve a rest!  Many thanks to everyone, I hope you agree it is worth the effort.

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