Welcome to Ilkley Moor! This cache is one of a series of caches that will take you on a tour of some of the many geological features that you can find at this scenic location.
Ilkley Moor
Ilkley Moor is an area of upland moorland, covering 676 hectares. Internationally, this type of moorland is rare, despite being relatively common in the North of England, and as a result has significant nature conservation interest. Mosaics of heather moorland, blanket bog, acid grassland and flowing streams make up the character of Ilkley Moor. Mixed with these are small stands of pine woodland, scattered trees, tarns and exposed rock faces.
Ilkley Moor is underlain by a succession of shale and course grained sandstones including the Addingham Edge Grit that forms the Cow and Calf rocks. The sand that forms these rocks was originally laid down on shifting sandbanks in a great river about 320 million years ago during the Carboniferous Period.
Deep burial caused the sand to harden into rock and subsequent earth movements and erosion brought the rock back to the surface again. By the end of the Ice Age, about 13,000 years ago, ice had scoured the moor and deposited the long low ridge of Lanshaw Delves, a glacial moraine. Since then peat has accumulated in sphagnum bogs.
Flagstone Paths
As the first Earthcache in the series, this is an easy one to get you going, not far from the parking area. At this location large stone slabs have been placed to form the path. This has been done to aid moorland conservation and enjoyment by helping channel walkers and preventing wider damage to soils and vegetation. They also keep your feet nice and dry in the rain!
Looking at the slabs, you should notice that they have clear ripple marks. Ripple marks are sedimentary features, and indicate agitation by water or wind. There are different types of ripples:
- Asymmetrical ripples are caused by the one-way flow of a river. They are distinguished by uneven dips, which are steeper on the up-stream side and shallower on the downstream side. They can be straight, sinuous (curved) or linguoid (random).
- Symmetrical ripples are caused by waves. Because the flow of the wave goes in both directions, the agitation happens equally on both sides. The dips are therefore even.
- Wind ripples are caused by the wind. Like asymmetrical ripples they are caused by a one-way flow, this time the wind, which usually leaves smaller ripples.
Logging your Find
In order to log your find, please send a message to my profile answering the below questions. The answers can be found by visiting the location, reading the above description, and taking observations in the field.
Look at the flagstones beneath your feet.
- Please describe the ripples you can see (length, height, shape, width, etc.).
- Please also describe the ripples with regard to the types as described on the cache page.
- Explain what you think caused the ripples, using the information in the cache page to help you.
As Ilkley Moor is a stunning part of the world, you may optionally want to upload photos of your visit, of course I would love to see them! You can log your find immediately, but please send the answers within 24 hours. I will respond to your message as soon as I can. Logs where incomplete answers have been given, or where an email has not been received, may be deleted.