Shallow Water Tidal Ripple Patterns 1-3

Natural patterns in rippled water

Shallow Water Tidal Ripple Patterns 1-3 Photographs of natural patterns created by reflected sunlight on the crests of minor ripples in clear shallow seawater lapping with the incoming tide around the island of Burry Holms at the tip of the Gower Peninsula in South Wales. Here shown in negative format to highlight the intricacies of the natural designs.

Natural patterns in rippled water

Natural patterns in rippled water

Rochefort Slacks Water Ripples

The wind was blowing really hard across the navy blue water surface of slacks trapped behind the shingle banks at Rochefort Point. Rochefort Point is a short walk from the Louisbourg Fortress in Cape Breton, Nova Scotia. The ripples were tight packed and narrow, travelling at speed. The water was actually a brackish brown but reflected the clear blue of the sky resulting mostly in dark blue hues. From some angles and in certain lights the sun shone through the ripples revealing the reddish colour of the water. The low standing crests of the waves were so distinct that it seemed as if the water was viscous.

Ebb Traces in the Sand at Whiteford

Ripples patterns in wet sand at the beach

Ripple patterns in wet sand on the seashoreThe shape of natural abstract sand sculptures, like these ripples on the seashore, result from complex interactions of water and substrate which are the subject of much research in the field of fluid mechanics. They are described as “small-scale three-dimensional bedforms due to interactions of an erodible bed with a sea wave that obliquely approaches the coast, being partially reflected at the beach” (Roos & Blondeaux 2001). Different combinations of three main perturbation agencies create different ripple designs.

REFERENCE

Roos, P.C. and Blondeaux, P. (2001) Sand ripples under sea waves. Part 4. Tile ripple formation, J. Fluid Mech.  vol. 447, pp. 227-246.

Ripples patterns in wet sand at the beach

Ripples patterns in wet sand at the beach

Ripples patterns in wet sand at the beach

Ripples patterns in wet sand at the beach

Ripples patterns in wet sand at the beach

Wave-induced sand ripples with drainage patterns

Natural sand ripple patterns with dendritic drainage channels

I thought this was an interesting phenomenon. Wave-induced sand ripples, that were merging into a tide pool at the base of the cliffs at Rhossili on the Gower Peninsula, had curvilinear and compressed dendritic drainage channels in the narrow valleys between the ridges.

Sand Ripples on Weymouth Beach

Seashore sand ripple patterns

These pictures were taken yesterday on the beach at Weymouth in Dorset, UK.   Very different from the sand patterns on Rhossili Beach shown previously. Some natural sand ripple designs that I’ve never seen/noticed before!

Seashore sand ripple patterns

Seashore sand ripple patterns

Seashore sand ripple patterns

Seashore sand ripple patterns

Seashore sand ripple patterns

Seashore sand ripple patterns

Seashore sand ripple patterns

Seashore sand ripple patterns

Seashore sand ripple patterns

Seashore sand ripple patterns

Seashore sand ripple patterns

Seashore sand ripple patterns

COPYRIGHT JESSICA WINDER 2014

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Stony Ripples from Ancient Seabeds

 Rock with preserved seabed ripples

There are many strange and interesting shapes and textures in the rocks on the beach at Mewslade Bay on the Gower Peninsula in South Wales. Most of them seem to be the result of weathering and erosion but these photographs show something different, unique, for that location. They appear to be preserved (fossilised if you like) ripple marks from the ancient seabed sediments of which the rocks are composed and date very approximately to about 350 million years ago. They have a distinct patterning which is very familiar from the sand and mud of present day seashores in the same area.

The rock itself is High Tor Limestone from the Carboniferous Period. Actually, It’s a bit old fashioned now to say just Carboniferous Period. Everything has changed. To be more accurate, I should say that the High Tor Limestone Formation is part of the Pembroke Limestone Group, which originated in the Visean division of the Dinantian, which in turn is part of the Mississippian sub-division of the Carboniferous Period.

What were at one time horizontal seabed surfaces have become near vertical over many millions of years of earth movements. The now-exposed surfaces of the old bedding planes are revealed in the entrances to caves at Mewslade Bay. The photographs show them encrusted with recent colonies of living acorn barnacles and occasional limpets.

Reference

Howells, M. F. (2007) Wales, British Regional Geology, British Geological Survey, Keysworth, Nottingham, UK, ISBN 978-085272584-9, pp 112 – 125.

Rock with preserved seabed ripples

Rock with preserved seabed ripples

Rock with preserved seabed ripples

Rock with preserved seabed ripples

COPYRIGHT JESSICA WINDER 2013

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Changing ripple patterns in a beach stream (3)

Another in the series of short video clips recording the wonderful changing ripple patterns in a shallow beach stream at Rhossili beach – because the phenomen is amazing and is delightful to observe. 

COPYRIGHT JESSICA WINDER 2011

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Reticulated ripples

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When, by chance, the sand grains on Rhossili beach are ill-sorted by the sea, the shore retains water in the sandy interstices as the tide recedes. Expanses of seashore can, for this reason, be covered by a thin surface film of seawater. The wind, blowing across these most shallow of ponds, disturbs the water and creates ripples. Swirling gusts of wind push the water in all directions – the ripples travelling in one direction are soon met by ripples from another direction. The result is a natural mosaic-like reticulated pattern of ripples – natural abstract works of art.  These photographs of the reticulation phenomenon have been digitally enhanced to introduced a new, brighter colour scheme that brings out the details of the patterns. 

COPYRIGHT JESSICA WINDER 2011

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Changing ripple patterns in a beach stream (1)

CLICK ON THE PICTURE ABOVE TO START THE SHORT VIDEO CLIP

I understand neither the physics nor the mathematics of the phenomenon but I think these evolving ripple patterns must demonstrate something about Chaos Theory.

Whatever, these naturally-occurring sunlit ripple patterns  are amazing. The regular diamond-shaped design changes to an irregular rectangular one and then back again. I recorded these moving, changing, reticulated patterns in the flowing waters of a braided stream running across Rhossili Beach on the tip of the Gower Peninsula. Just standing still and watching one part of the flowing water.

The sounds in the background include the roar of the nearby waves, the sounds of children playing on the seashore, and the slooshing steps of someone walking past through the surface water film.

COPYRIGHT JESSICA WINDER 2011

All Rights Reserved