Woodgrain on Old Church Cliff Breakwaters

Posted on September 29, 2017 by winderjssc

The amazing thing about the weathered timbers in the old breakwater constructions at Church Cliff in Lyme Regis was the woodgrain. Sinuous curves of ridges and grooves in the water-etched wood seemed to mimic the waves themselves, sometimes gentle, and sometimes with crashing surf. Tiny pale barnacles living in the grooves resembled sunny day sparkle spots on the waves, and were keeping company with small marine snails and black lichen taking advantage of the relative security offered by the wooden hollows.

Macro shot of rust-stained woodgrain in a breakwater timber

Wave-like water-etched woodgrain patterns in breakwater timbers

Ridges and grooves with resident barnacles in water-worn timber of an old breakwater

Curvilinear etched woodgrain patterns in weathered timber on a seashore breakwater

Wooden breakwaters with rusty iron fittings on the seashore

Curvilinear ridges and grooves in water-worn timber of an old breakwater

Curvilinear ridges and grooves with barnacles in water-worn timber of an old breakwater

Old breakwater or groyne projecting into the waves

Sea Foam Tide-marks on Rusty Iron

Posted on September 24, 2017 by winderjssc

Dried sea foam on rusty iron

I noted an interesting phenomenon at Weymouth in Dorset recently. The rusty iron panels of the pier structure exhibited tide-marks or tide-lines of dried sea foam from a previous high water. I have never seen that before. The contrasting colours, patterns, and textures of the creamy lines against the multi-coloured oxidising metal made interesting compositions.

Wikipedia says about sea foam:

Sea foam, ocean foam, beach foam, or spume is a type of foam created by the agitation of seawater, particularly when it contains higher concentrations of dissolved organic matter (including proteins, lignins, and lipids)[1] derived from sources such as the offshore breakdown of algal blooms. These compounds can act as surfactants or foaming agents. As the seawater is churned by breaking waves in the surf zone adjacent to the shore, the presence of these surfactants under these turbulent conditions traps air, forming persistent bubbles that stick to each other through surface tension. Due to its low density and persistence, foam can be blown by strong on-shore winds from the beachface inland.

Looking seawards along the iron pier work showing sea foam tide lines

Lines of dried sea foam on a rusty iron pier

Pattern and texture of dried sea foam on rusty iron

Lines of dried sea foam left by the receeding tide on a rusty pier

Pattern of dried sea foam tide lines on a rusty iron pier

Close-up texture of dried sea foam on rusty iron

Looking upshore at the rusty iron pier supports with lines of dried sea foam and attached seaweeds

Tide marks or tide lines of dried sea foam on the vertical rusty iron surfaces of pier supports.

Dried sea foam on algae-coated rusty iron

Contrasting colour and texture of dried sea foam on rusty iron

Seaweed Strands with Crinkled Kelp

Posted on August 12, 2017 by winderjssc

Seaweed textures and patterns in the strandline

Thick mats of seaweed wash ashore on beaches along the Jurassic Coast. Dead seaweed is often automatically viewed as horrid, unsightly, and a nuisance – but if you pause and look, there is beauty in it. There are many types of seaweed to be discovered in the masses on this strandline. Their fronds intertwine in a kind of accidental natural weaving. Each species has its own characteristic shape, texture, and pattern. Their combined presence forms greater abstract designs of infinite variety, the individual fronds making strands or threads as in a tapestry. The puckered patterns of the crinkly Sugar Kelp stand out as the most decorative features of the assemblage. The colours change from deep olive brown to golden yellow and cream as the algae decompose. The textures range from leathery to satiny, from slimy to crispy depending on moisture content. Opaque and hardening on exposure to air; or translucent and soft when floating in shallow water rock pools.

A walk around Normanby Island – Part 2

Posted on June 1, 2014 by winderjssc

Mystery beach find - possibly fish teeth - on Normanby Island

Button Shell on the beach at Normanby Island

Beachcombed finds on rock at Normanby Island

Nerite gastropod molluscs living in a rock pool on Normanby Island

Natural pattern in bedrock on Normanby Island

View of the rocky end of Normanby Island

Layers of modern "beach rock" or cay sandstone on Normanby Island

Fruits on the ground beneath trees on Normanby Island

Water pattern with fish shoal in shallow water

Close-up of pattern and texture in coral on the beach at Normanby Island

Pandanus fruits of bleached coral fragments on the shoreline at Normanby Island

Coral embedded in "beach rock" or cay sandstone on Normanby Island.

Pattern and texture in shallow lapping water on Normanby Island

Piece of dead coral on the beach of a tropical island

Coral embedded in cay sandstone (beach rock) on Normanby Island

Layers in a rock boulder on the beach at Normanby Island

Empty sea urchin test on rock at Normanby Island

Live rock oyster attached to dead coral on the beach at Normanby Island

Pieces of dead coral on the beach at Normanby Island

View from the trees to the beach on Normanby Island

Moulted crab shell in rock pool on Normanby Island

Trochus niloticus shell on the beach at Normanby Island

View of cay sandstone with eroded rock pools on the beach at Normanby Island.

Bleached coral on the beach at Normanby Island

Ringstead Bay Rock Textures & Patterns – Part 3

Posted on March 9, 2014 by winderjssc

Another gallery of close-up photographs showing natural colour, textures and patterns in an assortment of rocks on the beach at Ringstead in Dorset, England, illustrating the great variety in the geology of this stretch of World Heritage Coast.

Ringstead Bay Rock Textures & Patterns – Part 2

Posted on March 8, 2014 by winderjssc

Close-up of a flint nodule embedded in chalk

Close-up of iron staining in Wealden Beds rock

Close-up of the inside of a septarian nodule

Iron-stained Kimmeridgian mud and shale in a landslide at Ringstead Bay

Close-up of the weathered surface of Nodular Chalk

Detail of pieces of Kimmeridge Shale embedded in Kimmeridge Clay

Odd pattern in a rock from a landslip at Ringstead Bay

Pebbles and gravel stuck in Kimmeridge Clay

This is a gallery of some of the rock textures and patterns found in material brought down to the seashore by land-slips on the eastern half of Ringstead Bay in Dorset, England. Some might say that the geology of this half of the bay is much more complex and interesting than the western half. In addition to a natural progression of strata from older rocks in the west to younger rocks in the east, there are faults and land-slips that result in much of this variable material appearing in mudslides at the top of the shore, and as boulders on the beach.

The pictures show details of the textures and patterns in some of the rocks and sediments that were laid down after the Ringstead Formation rocks that were illustrated in earlier posts. These later strata include those from the Jurassic Period Kimmeridge Formation (shales and clays), Portland Limestone Formation (Portland Freestone, Portland Cherty Series, Portland Sand), and the basal part of the Purbeck Formation. The layers can be seen in exposures west of Holywell House on top of the ‘cliff’; and boulders from them often end up rolling down to the beach below.

A bit further east the geologically more recent Cretaceous Period strata are exposed. These include the Gault, Greensand, and Lower, Middle, and Upper Chalk. All of these rock exposures are subject the slippage and land slide so that boulders frequently end up on the beach. I haven’t yet reached a complete understanding of the geology in this location. I have attached a description to each image that you can see if you click to enlarge the pictures. However, I cannot say with absolute certainty the identity of each of the rocks I photographed – but I am working on it with the help of the references listed below; and I’m hoping to visit the Dorset County Museum to look at their rock collections soon.

REFERENCES

West, I.M. 2013. Ringstead Bay to White Nothe: Geology of the Wessex Coast (Jurassic Coast, Dorset and East Devon World Heritage Site). Internet field guide. By Dr. Ian West, Romsey, Hampshire and Visiting Scientist at Southampton University. http://www.southampton.ac.uk/~imw/Ringstead-White-Nothe.htm. Version: 19th December 2013

British Geological Survey (2011) Geology of south Dorset and south-east Devon and its World Heritage Coast, Compiled by M. A. Woods, Special Memoir for 1:50 000 geological sheets 328 Dorchester, 341/342 West Fleet and Weymouth and 342/343 Swanage etc, NERC, ISBN 978 85272 654 9.

Melville, R. V. and Freshney, E. C. (1982) British Regional Geology: The Hampshire Basin and adjoining areas, 4th edition, Institute of Geological Sciences, NERC, HMSO, ISBN 0 11 884203 X.