Whitby Jet?

Whitby jet

Planting the runner beans yesterday I came across this bead – or perhaps I should call it a stud, as the cylindrical cavity in it doesn’t go right through. It’s exactly one centimetre across.

Whitby jet

In close up you can see that it’s not cut with machine precision. That could be clay that’s filled the cavity but I’m leaving it in place for the moment in case it’s a part of the original artefact – some kind of cement, for instance?

Yorkshire Rock book

As I explain in my book Yorkshire Rock, a journey through time, Whitby Jet is fossil monkey puzzle wood from the Jurassic Period, used by the Victorians for making jewellery.

We’re meeting up with some friends, Jenny and Clive, on holiday at Whitby in July and Jenny, who has never visited is determined to find a piece of Whitby Jet on the beach. That could easily take up the entire holiday, so perhaps we better take this piece as a stand-by.

Link

Yorkshire Rock

Yorkshire Rock, a journey through time, available from my Willow Island Editions website

Shelly Limestone

fossils

Jurassic fossil shells in the limestone of High Oaks Grange holiday cottages near Pickering.

fossils

Selwicks Bay

Selwicks Bay

Dipping back in my A-level field notebook and in those pre-digital days, I found that colour prints could be more useful than slides, as I could stick them in my notebook. Here I’ve indicated a fault in the wave-cut platform of Selwicks Bay, Flamborough Head.

Flints in Chalk

flints
Flints in chalk

Flints are exposed in the chalk of the wave-cut platform south of the fault. Flints like these may have formed when the silica-rich skeletons of sponges and other creatures formed a gel on the seafloor which was drawn down into burrows in the chalk ooze – hence the shape of the nodules.

Buttress of Contorted Chalk

RockWATCH group guided around the features of the bay by geologist Richard Myerscough.

We looked at a buttress of contorted chalk south of the fault. The chalk contorted by the fault has been re-cemented by calcite-rich fluids circulating through the rock and depositing veins of calcite.

Strengthened by this cement the chalk is harder than that surrounding it and it has withstood erosion and formed a buttress.

Contorted Chalk with Calcite Veins

calcite vein

This vein is exposed on the wave-cut platform in front of the buttress.

Tilted layers near at the fault plane
Fault breccia: chalk crushed by movement along the fault
Fault and crush zone, Selwicks Bay, Flamborough Head

Fossil Raindrops

fossil raindrops
sandstone
Cross-bedding in another sandstone block in the wall.

These dimples in the surface of a stone in the wall at Blacker Hall Farmshop Cafe look to me like fossil raindrops. Rain fell onto soft wet sand causing those little craters then another pulse of sediment covered them and the process of lithification started, turning the beds of sand into sandstone.

fossil raindrops
delta

This is coal measures sandstone so this happened about 300 million years ago. At that time large river deltas extended across this part of Yorkshire.

The bed of sand must have been temporarily above water level for the raindrops to make their mark, so this would have been on the exposed upper surface of the sand. What appear to traces of bedding run across this block of sandstone, suggesting we’re actually looking at a side view of the bed of sand but I think the explanation for this might be that parallel bands of minerals have settled out as the sand gradually became dewatered and iron rich minerals were deposited.

Perhaps I need to take my pocket microscope next time we call at the cafe. The buckwheat pancake with strawberries, blueberries and Nutella makes that an attractive proposition for a geology field trip.

Prehistoric Planet

diplodocus

Watching Prehistoric Planet, launched on Apple TV this week, reminded me of the first book that I illustrated in colour, John Man’s The Day of the Dinosaur, published by Bison Books in 1978.

Prehistoric World, Carroll Lane Fenton, 1957.
‘Prehistoric World’, Carroll Lane Fenton, 1957.

I can see the influence of a favourite book from my childhood, Prehistoric World, written and illustrated by Carroll Lane Fenton, in my drawing of Diplodocus but my use of colour was based on a method used by Frank Bellamy in his Eagle comic strips Fraser of Africa and Heros the Spartan.

diplodocus spread
The book designer thought their was something missing from this spread so he got me to draw the foreground Diplodocus and, in those pre-Photoshop days, he carefully trimmed it out and pasted it onto the artwork.

As the book was printed using the standard CMYK four-colour process, I used just three bottles of ink – red, blue and yellow – mixing them to get my greens, browns and – as Bellamy called them – ‘phoney greys’. But instead of the regular black for the line work, I used sepia brown ink.

Day of the Dinosaur title page

I can see that I went a bit too much towards the brown with this title page. This shot of a smaller dinosaur scampering nervously beneath one of the larger species is used to good effect in Apple TV’s Prehistoric Planet and the designer of the book told me that the rough that he’d drawn for this spread helped them sell the project to a publisher.

My reference for the background for the title page came from my sketchbooks from one of the glasshouses at Kew and from my stints as a volunteer warden at the RSPB Loch Garten osprey reserve.

Tyrannosaurus Rex and Corythosaurus

Looking at my first attempt at this Tyrannosaurus Rex attacking Corythosaurus, the designer said, ‘I want the kind of tension you get you try to take a bone from a dog.’

This was the best I could do.

T. Rex v. triceratops

Prehistoric Planet features at T. Rex that has just made a Triceratops kill and I have to admit they’ve caught that ‘dog with a bone’ tension in their CGI, with muscle and sinew convincingly present beneath the skin, but they do have a team of experts to help them. I had to make do with my brother Bill (off work on sick leave at the time) making up and painting every dinosaur plastic model it that I could lay my hands on.

T. Rex v. Triceratops

I held the T. Rex model close to my eye to try and get the effect of it looming above the camera and I remember constructing a rough perspective grid to box in its proportions. I rotated my model of Triceratops to build up the herd.

Quetzalcoatalus

In Prehistoric Planet there’s a sequence of the pterodactyl Quetzalcoatalus, nesting in a luxuriant tropical forest. It had been recently discovered when I illustrated the book and I imagined it in an arid savannah type setting, feasting on a brontosaurus carcass as vultures might gather at a kill today. I couldn’t work out how Quetzalcoatalus, the largest flying animal that ever existed, could then have taken off again, after it had filled up on food.

Prehistoric Planet makes its initial hop and glide look aerodynamically convincing.

Corythosaurus
Corythosaurus

As this was my first set of book illustrations in colour, it was a bit of landmark for me as I started on my freelance career and, to borrow them for an exhibition, I approached the publishers, Bison Books, then operating from a basement in Cromwell Place, just opposite the Natural History Museum. Could they look them out and take them round to the RCA Illustration Department just across the road, where the then head of illustration, Quentin Blake was organising the show.

No luck. I remember that managing director looking at me as if I was making an outrageous request.

So if you’re the current editor of Bison Books, and you happen to be reading this could I remind you that it’s about time that you handed back the originals please?

Whitby Ammonites

Ammonite in boulder clay cliff
ammonite cartoon

As we walked along the beach between Sandsend and Whitby on Friday morning, I spotted this ammonite fossil embedded in the boulder clay cliff. The closely spaced ribs are almost straight, so that it reminded me of a section of reinforced hosepipe.

Dactylioceras was a slow swimming ammonite from the Early Jurassic. This looks like a fragment of the shell of Dactylioceras tenuicostatum, a common fossil found in the Whitby Mudstone Formation at locations such as Port Mulgrave.

calcite crystals

The hollow chamber inside the shell has been filled with calcite crystals.

Hildoceras

Hildoceras ammonite fossil

Hildoceras, also from the Early Jurassic has sickle-shaped ribs and a groove along the triple-keeled groove along the outer edge of the shell.

Hildoceras keel
Triple-keeled groove of Hildoceras

Hildoceras features on the title page of my book Yorkshire Rock, a journey through time, which was published 25 years ago by the British Geological Survey (see link below).

Yorkshire Rock

There’s a folktale that they’re the fossilised remains of serpents, driven from the cliff top at Whitby by Abbess St Hilda.

Link

Yorkshire Rock, a journey through time at my website Willow Island Editions

The Beech Farm Brachiopods

fossil shells

The oolitic limestone of the North York Moors was laid down in a warm tropical sea about 160 million years ago in the Jurassic Period. In close-up, oolite resembles tiny round white fish eggs, hence the name.

The spiral shells are, as you might suspect, molluscs, but the thick mussel-shaped shells are brachiopods, also known as lamp shells because of their resemblance to Roman oil lamps.

View from Beech Farm Cottages
View from Beech Farm Cottages

I spotted them in the walls of Beech Farm Cottages, Wrelton.

shells in oolite
Calcite crystals have replaced the original material in this fossil mollusc shell.
Shelly limestone: these brachiopod shells are mostly aligned concave side upwards, probably because of a current sorting the sediment and depositing them on this part of the seabed. Because this block has been built into a wall, we can’t tell which way up it was when the shells were deposited.
Entrance to Beech Farm Cottages. These corners stones or quoins are traditionally made from sandstone in the North York Moors because limestone isn’t as suitable for cutting to a sharp edge. In the absence of suitable slate or flagstones, pantiles became the preferred material for roofs. The stone bracket at the corner of the roof is a kneeler.

Drawing Fossils

On the University of Southampton’s FutureLearn course Beneath the Blue: The Importance of Marine Sediments, we’ve been asked to draw our favourite marine invertebrate, using the techniques of scientific illustration. My favourite would have been the octopus but, as I didn’t have one available, I’ve opted for my favourite fossil marine invertebrate, a rugose coral, Zaphrentis phyrgia. I found it in a patch of crushed limestone on a forest track in the Dales. It dates from the Early Carboniferous.

Zaphrentis
zaphrentis
Pen and watercolour drawing for ‘The Dalesman’.

We were asked to make a measured drawing but I needed to scale it up to fill 75% of the page, leaving room for captions. Using a pair of compasses, I measured the fossil in centimetres, doubled that length then converted to inches for the drawing, so the 5cm height of the actual fossil becomes 10 inches on the drawing.

Measured pencil drawing in A4 sketchbook

The scientific method of drawing stipulates line only with no shading, which is very different to my usual pen and wash technique. I drew the fossil for the August edition of The Dalesman.

Dalesman August 2019

Final Version

In Photoshop, I converted the pencil to black and white and replaced my hand-lettering with a similar-looking font.

Solitary rugose corals were common throughout the Carboniferous Period and some survived until the late Permian. There were four main radial septa which divided the coral so that it was bilaterally symmetrical. Present-day hard corals are sometimes referred to as hexacorals because they have six main divisions.

As I wrote in The Dalesman:

Zaphrentis phrygia was given its species name because of its resemblance to the Phrygian cap of ancient times: a tall, pointed felt cap, which was worn with the point tilting forwards. The living coral stood the other way up, with its pointed end in the seabed.

Richard Bell’s ‘Wild Yorkshire’ nature diary, ‘The Dalesman’, August 2019

Link

University of Southampton FutureLearn course Beneath the Blue: The Importance of Marine Sediments

The Dalesman ‘Yorkshire’s favourite magazine. Since 1939 we have been celebrating all that’s great about Yorkshire, God’s Own Country, through the pages of our magazines, books and guides.’

Fossil Sponge from Flamborough

This fossil sponge was collected from the beach at Selwicks Bay, Flamborough Head, on a Rockwatch weekend in the early 1990s.

It was embedded in a fragment of chalk that had fallen from the cliff, so it dates from the Upper Cretaceous Period, 95 to 65 million years ago. I drew it for my 1996 book Yorkshire Rock, A Journey Through Time but since then the chalk that surrounded it has split into shards. The collar of the smaller sponge has disintegrated too.

How I imagine it might have looked, growing in the chalky ooze of the Cretaceous sea bed.

Sponges were common as the age of the dinosaurs drew to a close. They had a sac-like body with a central cavity known as the cloaca.

The nearest species that I can find is Laosciada, a mushroom-shaped lithistid, a kind of demosponge, informally referred to as a calcisponge. It lived in deep water, between 100 and 400 metres.

The skeleton of the collar of this sponge is made up of interlocking spicules, which look like little pyramids in close-up. They’re made of silica which, remineralised, forms the layers of flint found in the chalk.