Golfing with Dinosaurs: a lockdown geology story
In my May 2020 email newsletter to YGS Members, I rashly promised to prepare a virtual field trip to the Triassic of Edwalton Golf Course. Fortunately the lockdown is easing and demand ( if there ever was any) is declining, so I’ve written this blog instead as a blast from the past, an ‘ex-President’s Word’.
Unlike many, if not most retired British Geological Survey (BGS) geologists, I haven’t moved to Yorkshire, instead staying in the East Midlands and helping to run the YGS from there. So no fascinating Yorkshire geology and stunning scenery for me on my one hour Corona-lockdown walk. Edwalton is an outlier of West Bridgford on the southern outskirts of Nottingham, part of the borough of Rushcliffe. It’s handy for Trent Bridge cricket and second tier football at Forest’s City Ground, the theatre of dreams gone by from the days of Brian Clough. As a place to live, Rushcliffe has a lot going for it, but it’s not a mecca for geological tourists, and no-one is working on a geopark application. But many geologists live there, because BGS Keyworth is just down the road.
Donkey’s years ago, when I had time, I used to play golf. Edwalton has a municipal golf course, owned by Rushcliffe Borough Council, so it was recently left open for local lockdown walkers to enjoy. It’s just a nine hole course, and I was once one of a small group of BGS colleagues who met up after work for a round, which would take about an hour and a half. Three of us are still YGS members. Although short on holes, Edwalton Course is long on difficulty – it’s punishingly tough, partly because of its geology. More on that in a minute.
The bedrock below Rushcliffe is mainly Triassic Mercia Mudstone, ascending up to the Penarth Group and early Jurassic Lias Group on the south-eastern fringes of the borough. Much of Edwalton is underlain by the eponymous Edwalton Member (of the Sidmouth Mudstone Formation, Mercia Mudstone Group MMG). The MMG forms a distinctively red and very heavy soil, very hard to plough without modern agricultural machinery. BGS mapping geologists used to call it the ‘Merciless Mudstone’ because it accumulates on one’s boots, kilograms of it, when the ground is wet. During droughts (as we are experiencing now (in May 2020)) it sets as hard as bricks. The good people of Nottingham knew this, and dug brick pits into the MMG all over the area in the 19th and early 20th century to build their city.
Nowadays there is only one working brick clay quarry near Nottingham, at Arnold to the north of the city. Most of the old brick pits are overgrown and exposures of MMG are few and far between. But there is one pit in my one hour lockdown walk radius that still has an exposure, albeit very overgrown. This is the Ludlow Hill brick clay quarry, now occupied by housing and small industrial units, and formerly home to the BGS Keyworth core store back in the 1980s. This exposes the Cotgrave Sandstone (see photo below), which is early Carnian in age, and the first manifestation in the East Midlands Triassic succession of a major climatic episode that was to change life on Earth for ever.
Ludlow Hill brick clay quarry, West Bridgford, Nottingham, photographed in 1908. Image number P200719 from the British Geological Survey Geoscenic collection.
During my time as YGS President, YGS was fortunate to enjoy talks from Alastair Ruffell and Mike Benton, two of the UK-based geologists who have led international research on the global environmental and biotic changes that took place in the late Triassic Carnian stage, around 230 million years ago. With colleagues, they are uncovering a growing body of evidence that a major atmospheric perturbation, perhaps driven by the eruption of Large Igneous Provinces associated with rifting and the break up of Pangaea, led to a major episode of global warming, climatic instability and both faunal and floral taxonomic turnover during the Carnian stage. In the interior of Pangaea, previously arid climates fluctuated back and forth to humid, leading to extinction of many long established terrestrial taxa and replacement by others that could take the opportunities presented by major changes in global flora distribution. This ‘Carnian Pluvial Event’ saw the ‘explosion’ of new taxa of dinosaurs, that were to rule the earth for another 170 million years to the end of the Cretaceous. Most importantly, the same episode saw expansion of the ancestors of modern and familiar tetrapod groups, such as crocodiles, lizards, turtles and mammals.
What has all this got to do with Edwalton Golf Course, and why is it so difficult? Much of the course is constructed on the dip slope of the Arden Sandstone, a distinctive and mappable formation of fluvial sandstones and alluvial mudstones in the Midlands, quite different from the red, ‘arid sabkha’ mudstones of the beds above and below. The Arden Sandstone marks the top of the Carnian stage, and the approximate end of the late Carnian Pluvial Event. In the Nottingham area the Arden Sandstone is a heterolithic unit of interbedded sandstone and mudstone, and gives rise to a much lighter, loamy soil than is typical of the MMG. It was easier to till with medieval hand ploughs and oxen, so the dip slope of the Arden Sandstone on the golf course still preserves extensive medieval ridge and furrow, often crossing the fairways at an oblique angle (see photo below). The course also meanders up and down a low scarp formed by the Sandstone, creating blind summits on many of the holes. Golfers therefore have to hit many of their shots over these summits, so even the straightest of shots down the middle of the fairway can hit one of the furrows at an angle and go flying off unseen into the deep rough (so I’m told, I always took the more direct route straight out of bounds). It’s all a bit unfair, and quite a golfing challenge.
Medieval ridge and furrow preserved on the dip slope of the Arden Sandstone Formation, Edwalton Golf Course, near Nottingham. Photo: Andy Howard April 2020
The (par five) first hole at Edwalton can serve as a proxy for geological time. Firstly, you tee off on the early Carnian, a little way above the Cotgrave Sandstone, in the company of primitive reptiles. You then chase your small ball up the scarp of the Arden Sandstone and through the global change of the late Carnian Pluvial Event. Eight shots later (if you’re as bad at golf as I was), you putt out on the 1st green in the late Carnian, at the dawn of the age of dinosaurs.
Now that Yorkshire is welcoming visitors, I hope to get back there soon and see some classic geology again. But every place on Earth has a geological story to tell, even where it’s hidden from view. That’s what makes our science so fascinating, even when times are ‘ard.
Andy Howard
General Secretary, Yorkshire Geological Society
June 2020
Further reading:
Ruffell, A., Dal Corso, J. & Benton, M., 2018. Triassic extinctions and explosions. Geoscientist 28 (8), 10-15 (2018). https://doi.org/10.1144/geosci2018-007
Andy Howard, 2006. From the archive. Ludlow Hill Brick Clay Quarry. Mercian Geologist 16 (3), p.15
Download the pdf of Mercian Geologist 16(3) here