Recently the South Downs in Southern England became a National Park, granting the region a boost to tourism, altered planning regulations and plenty of new signs (amongst other things). The new national park has a website, designed to both attract visitors and give local people more information about, what is in essence their local authority.
The National Park Authority |
Geologically, the South Downs National Park are an area of Chalk, Early Cretaceous clays and sandstones folded by the Wealden anticline during the Cenezoic. The actual ‘downs’ themselves are the remains of the chalk cover that once stretched across the Weald to just south of London. So, what does the website (and therefore we can assume most of the paperwork) from Britain’s newest National Park have to say about the rocks?
Well firstly, where is Geology on the site? Logically it would be accessible under Learning, which it is, but within that subsection it is hidden under the unexciting ‘Themes to Study’ – not exactly going to entice too many people into the regions geology. The site blurts on about the beautiful landscape – but seems to hide the factors behind the landscapes formation.
‘To really appreciate the South Downs landscape you need to understand how it was formed.’ South Downs National Park Site
Apparently, Most of the rocks that make up the South Downs were formed 120 million years ago – which is odd as Seaford Head, a promontory within the chalk is in fact the stratigraphic boundary between the Santonian and Campanian - 83 million years ago. While stratigraphically the lowest rocks in the new National Park, the Wealden Clay are considered post-Tithonian/pre W Aptian in age or for those without beards, 151-125Ma. In fact only the Lower Greensand and Weald Clay are the only rocks in the park’s boundaries that could be considered to have for. The site’s very own stratigraphic column even places only the lower units around the 120 Ma mark!
Coast of the National Park - an iconic image |
Moving on from the bigger picture, what about the individual units... as something that actually got me into geology in the first place. Flints...
‘Flint was formed from the skeletons of minute animals, such as radiolarians, that floated around in those ancient seas.’
Firstly, very few people know what a ‘radiolarian’ is, I’ve touched upon this within the GSL Q&A page; ‘remains of tiny creatures’ would have been better. Secondly, there is a lot of debate as to the generation of flint –it took me a good few minutes to track down a digestible paper – which indicates that the flint was formed via microbacterial activity. Surely it is more exciting to the reader to just be honest, say you don’t know, or give a couple of theories (wherever they may be hiding)
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