Anyone new to this blog or geophysics in archaeology is recommended to read the material on the “Geophysical survey in archaeology” page.
Not long after we arrived home after a busy week on site, the heavens opened. We’ve had 7.2mm of rain in the last 24 hours. Hopefully, not enough to create problems with the Earth Resistance survey, unlike the deluge we had the other week.
Mike Smith sent me this entertaining picture.
The Earth Resistance meter was manned by Ellen, Pauline, Graham and Fergus (CAGG’s mascot). They completed an excellent seven 20x20m grid squares including two partials with a big oak tree in the middle. Figs. 2 and 3 show the data “normally” and high-pass filtered.
The main feature of interest in the new area is the nice building in the top left-hand corner of the plot. The apsidal end of a room facing NE shows especially clearly. This building was known previously, partly from an aerial photograph taken in 1977 and partly from the English Heritage survey undertaken in 2000. We have much more of it, however. The buildings also show nicely in the mag data (Fig. 4).
We will fill in the odd missing squares on Wednesday.
The GPR was in the deep south of the Gorhambury side of the town, up on the hill near the King Harry Lane roundabout with marvellous views down across the theatre and the River Ver with the fields of ripe wheat on the opposite hill slope. That is after you have caught your breath…
The GPR team completed the block I was hoping to get done, and started on the next one slated for Wednesday. Good job! Here is the composite of six time slices (Fig. 5).
Slice 4 (Fig. 5, top right) appears to show a wall running NNW–SSE with a rounded corner. Here it is on Google Earth.
Slice 6 (Fig. 5, middle right, and Fig. 7) starts to show a clear building in the NE corner. This is supposed to be along a road which runs approximately parallel to the modern road, but which I cannot see in the geophysical data. The wall seen in the previous image is still visible on the northern side but does not show on the west.
Slice 8 (Fig. 5, bottom right and Fig. 8) shows the wall again on the western side as well as the northern. Curiously, the corner appears different. Comparison to the mag data (Fig. 9) is informative.
The line of the wall is clearly following the magnetic anomaly in this area, with two large circular anomalies on the corner. I had thought the anomaly was a ditch, but now I am less sure. It is clearer to see the relationship if one traces over the wall line from slice 8 (Fig. 10).
The differences in the corner can be seen if one then looks at slice 4 with the wall line from slice 8 marked (Fig. 11).
As can be seen from Fig. 11 the wall lines match perfectly apart from the corner. Was it rebuilt at some point, or do the reflections in slice 4 represent some wall collapse? I’ll need to examine the radargrams carefully to decide what is happening.
The ditches are marked on the “Urban Archaeological Database”. Isobel Thompson informs me that they have been interpreted as field boundaries for “Little Wynyards” in the 17th century. Perhaps a vinyard? As Isobel points out, there are the Vintry Gardens near the abbey which are in a walled enclosure. Just one more avenue of research to pursue to be able to interpret our complex data set.
Many thanks to Pauline, Ellen, Graham, Mike, Jim and Nigel for all their help. We’ll be back on Wednesday for the final week. Doesn’t time fly when you are enjoying yourself!