Air Balloon Geology

Recently a subscriber to this blog asked "I wonder if you know of any geological treatise on the A417 "Missing Link" at the Air Balloon pub site? ..... They plan to keep the strata exposed for all to see when driving past, like has been done on the Cirencester dual carrageway."

Well, the short answer is that I do not know what is happening there. If you do, send me the details HERE and I will pass them on. 

But the request sent me on a mission to discover what the geology is at the Air Balloon Pub. My knowledge of the place is being stuck in a traffic jam, waiting to get on to the M4 at Gloucester. And I discovered the latest addition to the BGS web site - the GeoIndex Beta.

With a little persistence I managed to produce the following map.

The original map can be found HERE.

If you click, on the original map, on a formation you get a pop-up similar to the following:-

The link takes you to THIS PAGE which tells you a lot about the Birdlip Limestone. The parent of this page IS THIS - the Lexicon of named rock units of the BGS.

I used this to name several of the formations on my Air Balloon map.

To search the Lexicon use the Computer Code given in the pop-up, or the Preferred Map Code. (This the code in the last line of the rock names I have put on my Air Balloon map.)

So now I know a great deal more about the Air Balloon Pub area and know how to access a vast amount of Geological Knowledge, but I still cannot answer the question which started this search!