Tuesday 31 May 2016

Loess in Britain II Airport Story

Once upon a time there was a plan to build a great airport in the Thames estuary. This was to be the main London airport, replacing rather than supplementing Heathrow LHR. This was to be the only airport built on loess(?) -that is a disputable statement for several reasons; there might be other loess grounded airports (in Timaru maybe) and in fact the proposed airport was only partially on loess ground. A lot of other geotechnically challenging sediments were involved. But it was to be the biggest project in Britain to involve loess (if one ignores the centuries of exploitation of the loess deposits nearby for the purposes of brick manufacture).
All this was happening in the 1970s and the project was soon cancelled: too expensive, too ambitious, too radical, it was a very un-British project- full of style and brio and imagination and foresight; it was quickly cancelled- but not before the British Geological Survey had been deployed to do a careful study of the region. This produced the best and most thorough study of loess in Britain- which was eventually published:

Northmore, K.J., Bell, F.G., Culshaw, M.G.  1996.  The engineering properties and behaviour of the brickearth of south Essex.  Quarterly Journal of Engineering Geology 29, 147-161.

It took 20 years for the material to be published (quite quick by BGS standards). The initial work was largely done by young, recently graduated engineering geology MSc students from the University of Leeds. They worked well and enthusiastically as young geologists, and as grizzled veterans saw their great works published. In this study thicknesses of loess of up to 8m were reported which makes south Essex an interesting loess region. Of course in the early 2000s the plan was resurrected, and(for the reasons cited above) will be rejected. Actually there is loess material involved at the Heathrow site- as will be discussed later in the 'Loess in Britain' blog sequence.



 

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