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From Aug 2006 - Nov 2013 WeDig provided a live forum for diggers & fans of Vindolanda. It has now been mothballed and will be maintained as a live archive.

Here you will find preserved 7 years of conversation, photos, & knowledge about a site many people love. Vindolanda gets under the skin. (Figuratively and literally as a volunteer excavator!) It's a place you remember, filled with people you remember!

Thanks for 7 great years!

Viewing Single Post From: Mike's Geoblog
Mike McGuire
Member
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Last Wednesday we were visited on site by Dr David Lawrence the county geologist for Northumberland. He and some of his colleagues from the British Geological Survey in Edinburgh have been giving us great assistance with the stone sources project. Iím pleased to say he was in agreement with many of the ideas Iíve been developing during this season. Iíve identified two sites in addition to those on Barcombe Hill which David agrees with me are probable quarry sites. As yet I donít have any specific evidence they are Roman but this does seem the most likely story.

Iíve also identified from the thin sections a possible way of distingushing stone from these quarries from the Barcombe Hill stone. But thereís still a lot more work to do on this and on Thursday, after careful discssion with Andy and Justin, I took 8 stones from the site from which, along with some of my quarry samples, we shall have some more thin sectons made.

There was one subject on which David was able to correct my ideas, which is about the famous green stones which crop up all the time in the excavations. As I said in an earlier blog, these come out of the boulder clay which underlies the site and I had correctly identified the green mineral as chlorite. However, David doesnít think the stones come from the Whin Sill; the dolerite rock which makes up the sill doesnít generally alter in such a way as to produce chlorite. The nearest widespread source of rocks which do chloritise, including igneous rocks such as andesites and also some metamorphic rocks, is the Lake District. This is consistent with the fact that the last movement of the ice during the last glaciation was from west to east and rocks from that direction such as Shap Granites are found in the area.

So the 2010 excavation season is coming to an end. Next Thursday we shall all say our goodbyes and Malise and I will be moving out of the house weíve been renting in Haydon Bridge. A great wrench to leave our fabulous view of the South Tyne valley for the boring suburbs of Derby. So my next blog will be the last of the regular season. Iíll share some of the deas Iíve been mulling over during the past 5 months and give you my suggestions for some further reading on Northumberland geology. Iíll put more enties in my blog as and when anything new crops up during the close season. Then itíll be the 2011 season and it all starts again!
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