Cape Enrage Rocks 2

Cape Enrage is one of the many spectacular stop-off points as you travel along the north shore of the Bay of Fundy on the east coast of Canada. The cliffs are composed of thick and thin layers of sandstones, mudstones, and conglomerates that built up along river beds and valleys about 320 million years ago. The ancient river channels can be seen in cross-section in the exposed and weathering strata. The way that the rocks are fracturing and splitting up into their component layers makes many intriguing natural abstract patterns. Plant debris that piled up on the river banks as it was washed downstream in the Carboniferous period has been preserved as fossils.

Cape Enrage Rocks 1

Cape Enrage in New Brunswick, on the north shore of the Bay of Fundy, is a popular site for visitors because of its fantastic geology. The rocks are composed of Carboniferous Period Ward Point Member sandstones and mudstones of the Enrage Formation and the Cumberland Group. The almost vertically inclined rock layers in the cliff fracture and weather to create wonderful abstract patterns. The sediments that make up the rocks are fluvial in origin, originally deposited by rivers, and the exposed cliff-section shows many in-filled river channels. Large areas of rippled surface can be seen where channels are exposed; this together with chunks of rock with cross-bedding is interpreted as point bars in which the channels were constantly migrating laterally (as in present day braided river channels before they enter the sea). Localities with conglomerate composed of sandstone with rounded pebbles represent the the centre of river channels where the flow was fastest, or where flash floods have deposited heavier loads.

Rocks Near Cape Enrage

West of the promontory bearing the famous Cape Enrage lighthouse in New Brunswick, across a wide wetland valley blocked by a shingle bank, is another spectacular promontory with pine topped cliffs. The rocks here belong to the Mabou Group of The Enrage Formation, part of the Cumberland Group from the Late Carboniferous Period. My visit was a brief one and I wished I had known at the time that this is a site where  fossils may well be found. Unfortunately, I didn’t know what to look for and simply marvelled at the natural rock textures and fracture patterns without discovering their hidden secrets. Further east on the shore beneath Cape Enrage itself I was much luckier and found some plant fossils – but more of that later!

Hyalophora cecropia mating

Video

A couple of years ago while I was in Nova Scotia, Canada, we stayed at a delightful bed and breakfast called the Baker’s Chest in Truro. Besides memories of the beautifully furnished house and gourmet breakfasts, the well-maintained garden had a wonderful surprise in store. The owner pointed out that a large moth had just emerged from under the decking and was drying its wings on the wooden trellis. A few hours later, there were two moths. The first had been a female and the newcomer was a male, attracted by the pheromones that she was giving out, and now the two were locked in the slow moving and elegant mating embrace that you can see in the video. They are Hyalophora cecropia, also known as the Robin Moth, and are the largest native moth in North America, with a wingspan that can reach 15 cm or 6 inches across.

Porthmeor Rocks 2

These rocks are seen on the west side of The Island or St Ives Head in Cornwall, England. They form outcrops on the west side of Porthmeor Beach. I was fascinated by the sheer complexity of the colours, patterns and textures. As far as I can make out they belong to an un-named igneous intrusion (matagabbro or metamicrogabbro) composed of silica-poor magma which was later altered by low-grade metamorphism in the Devonian period between 359 and 416 million years ago.

The rock looks very different from that nearby which was featured in an earlier post. I was particularly drawn some outcrops which had an almost dark navy blue smooth surface but the majority of the rock surfaces were blue-grey and dirty yellow shades – some with smoother almost layered textures and others textured like lumpy porridge. The patterns were complex but included ancient splits and cracks that had been infilled with other materials of contrasting colours, giving paler or darker straight lines and angled cross lines – not to mention all the complicated later fracture patterns. There seemed to be large inclusions of other rock types too; this often occurs in granites. It is incredible that rocks of the same basic type can vary so much in their appearance within a few metres.

Starfish Skeletons

Starfish, usually Asterias rubens, sometimes get washed ashore in huge numbers on Rhossili beach in Gower, South Wales. Then they disappear again, either washed back out to sea or buried in the sand. Birds peck at them but they do not seem to like to eat them very much. This April, for the first time, I saw ghostly star shapes in the dry sand high on the shore. The long buried stranded starfish were reappearing in skeletal form. You may not have realised that Asteroidean Echinoderms like the Common Starfish had a skeleton. Hidden beneath their often brightly coloured and bumpy skins, bound together by connective tissue, is a lattice network of small calcareous ossicles in the shape of rods, crosses or plates. Spines and tubercles are also part of the skeleton, sometimes separate pieces resting on the deeper dermal ossicles or as extensions of them that project to the outer surface (Barnes 1963).

In these photographs of the dessicated remnants of starfish it is possible to see many small holes in the sand around them. These holes are the places where the scavenging sand hoppers are hiding from the dry hot air and waiting from the tide to return in the cool of the day to recommence cleaning up all the vegetable and animal debris that ends up on the strand-line – like dead starfish.

Reference

Barnes, R. D. (1963) Invertebrate Zoology, R. B. Saunders Company, 526-539.

Embroidered Waves

Embroidered silk Chines festive dragon robes from the Qing DynastyA watery theme in textiles this time. These images show details of the designs on the hems on two Chinese silk embroidered dragon festive robes, worn by an Imperial consort and an Imperial prince during the Qing dynasty (1856-1908). They are displayed in a glass case at the Victoria and Albert Museum in London, England. The hems of the garments depict waves and surf while dragons fly overhead on the main body of the robe. If you look closely at the detail of the churning water, you may see small stalk-eyed crabs, sea snails with coiled shells, leaping blue fish, and strange sea anemones lurking in the foam.