Faults and faces, clints and grykes

This is from the top of Malham Cove, an 80 metre high, curved, limestone formation just north of the village of Malham in Yorkshire.

Millions of years ago, due to a fault line called the Mid Craven Fault, the land dropped, creating a 100 metre high cliff. Over the subsequent years, the limestone face has been worn away, eventually leaving the current curved crag.

This photo is taken from the other end of the curve, near to the top of the steps which descend to the valley floor.

The classic view of the Cove is from the bottom, showing the whole sweep of the curve. Far below me, I could actually see a whole cluster of people pointing cameras at the face. Unfortunately, I could also see the long line of steps and was all too well aware that the location of the car meant that what went down, would then have to come back up! 

I just wasn't that dedicated. Sorry :)

(If you want to see the classic view, click here.)

Looking out from the top, the view was beautiful. Undulating green fields, separated by dry stone walls and dotted with sheep. Malham is just visible left of picture and little pockets of woodland complete the scene. This is typical limestone country; a landscape known as karst (where water has shaped the carbonate bedrock). 

As you can see from the well trodden path running alongside Malham Beck, the Cove is a very popular destination!

The top of Malham Cove is a limestone pavement consisting of clints and grykes. The clints are the blocks and the grykes are the cracks (I have to look that up every time!). 

Limestone has a calcium carbonate chemical base. Because of this, it is readily soluble. Grykes are formed when water runs down the vertical joints of the rock and causes the limestone to dissolve. This process is called carbonation. Over time, the grykes deepen and the clints are left standing proud between them.

Shade loving plants flourish in the damp of the grykes. Some of the ferns and wild plants which grow here are relatively rare. Unfortunately, all I managed to photograph were some nettles!

Limestone dry valley

The outflow from Malham Tarn only remains overground for around 500 metres before it disappears through the permeable limestone, flowing underground for some distance, until it surfaces south of Malham village, becoming the source of the River Aire.

Above ground, it leaves this dry valley; an attractive example of limestone country!

Caves are common and this one reminds me of those in Dovedale, in my native Derbyshire.

The sheep is definitely Yorkshire though; a Swaledale.

Watlowes Valley finally opens out, leading us towards our destination.

Looking for the hole punch

In my last post, I asked if anyone could identify this.

Here comes a close up to help you :)

It's an orienteering marker.

Orienteering is a sport in which participants navigate their way around a course using a map and compass. It can be done competitively or just for fun, with people of all ages and abilities enjoying the experience of walking, jogging or running as they find their way around the markers.

At the Malham Tarn Field Studies Centre, a variety of courses are offered for KS2 children, including orienteering around the area of the Tarn. This is one of their markers.

The marker gives various bits of information. The card attached to the pole gives the location is the Cattle Grid and the map grid reference as 8973 6711; also, that the location symbol is a lizard. 

Orienteering competitions mark the orienteers progress with an electronic score card which is punched at each marker. An low-tech alternative is to carry an actual card which is marked by punching holes. As John rightly said, the red object dangling from the piece of string is the punch. As this marker symbol is a lizard, I imagine that the children would need to punch through a picture of a lizard on their card, to show that they had collected this marker. (Or maybe, the hole punch is a lizard shape??)

Having punched their card, the orienteer checks the last piece of information on the marker; the grid reference of the next location. And so the round continues.

Have you ever used a map and compass to navigate your way around a walk or course? 

I was interested to read Louise and Andy's comments about geocaching. It sounds like fun!

A stick with bits attached

On our way back round Malham Tarn, we spotted this.

Any idea what it's for?

Lady's Slipper

On the shores of Malham Tarn is a Field Studies Centre which is focussed on conservation and education. Amongst other things, this involves monitoring the water quality of the tarn and keeping a careful watch on the plant, bird and animal life around the Malham Estate.

They have also grown this...

At one time, orchids were a relatively common sight, growing as wild flowers around the Northern English countryside. Then came the Victorians; great plant collectors who virtually wiped out the native wild population of some orchids, including this one - The Lady's Slipper orchid.

As you can see, this specimen is being nurtured within a cage to protect it from predators - animal and human but, the long term aim is to re-establish a truly wild population.

Apparently, the last original native specimen of this orchid is on private land in a secret location somewhere else in the Yorkshire Dales (they do like the limestone soil), but in 1983, the Sainsbury Orchid Project was set up in Kew Botanical Gardens and this eventually led to the Kew scientists being able to grow the orchid from seed.

Since that time, small populations have been introduced to sites across Northern England; a joint venture between Natural England and the Wildlife Trusts of Yorkshire, Lancashire and Cumbria. Maybe, one day, these pretty little flowers will once again be common across the northern limestone counties.

A few interesting facts about the name:

It was named by Carl Linnaeus (1707-1778); a famous Swedish scientist who developed the Linnaean Taxonomy - the system of scientific classification now routinely used in biology.

Its Latin name is Cypripedium calceolus. 

Translated literally, Cypripedium means 'Venus's feet' and calceolus means 'little shoe'. As a result, some people still refer to the plant as 'The Little Shoe of Venus'.

In the USA, the plant is apparently known as the Moccasin flower

Malham Tarn SSSI, NNR, SAC, RAMSCAR

A short distance north of Malham, in Yorkshire, is Malham Tarn. A small lake with a surface area of 153 acres and a maximum depth of 14 feet, it is unusual for a number of reasons; as a result of which, it has been designated an SSSI (Site of Special Scientific Interest), NNR (National Nature Reserve) and SAC (Special Area of Conservation) as well as being listed as a RAMSCAR Site!

The Tarn is owned by the National Trust but, since 1947, has been leased to the Field Studies Council; the reason being that Malham Tarn and the associated wetlands have the greatest diversity of wildlife habitats of any upland lake in the UK.

In fact, at 377m above sea level, it is the highest lake in England.

Another feature which makes Malham Tarn unusual is that it has formed within an area of limestone, a permeable rock. The Tarn actually lies on a small bedrock of slate covered in marl; a calcium based mudstone which contains clay and silt. Because of this bedrock, the water of Malham Tarn has an alkaline pH; one of only eight of its kind in Europe!

The stream which flows out of the Tarn is only visible for about 500 metres, at which point it disappears, following underground channels through the limestone until it eventually emerges some 2 miles further downstream.

We weren't fortunate enough to spot a massive diversity of wildlife (though we did see a tree creeper), but we did have a close encounter with a small group of cows, including some calves, the mothers of whom were not too enthusiastic about our presence (on the footpath) in their field and approached us to do a bit of posturing to make their feelings clear.

After a bit of posturing of our own, they turned aside and we were able to back off and walk quietly on.

As you can see, it was a blustery day and walking by the edge of the water felt almost like being by the sea, the sound of the waves was so distinct :)

Starting out on Windgather

Just before the end of May, eldest son Mark and I, plus my Dad, drove up to Windgather Rocks in Cheshire, to meet a friend from Yorkshire. The purpose of the day was for Mark to give that friend a climbing lesson. 

Meet Sacristan, a friend with a very real fear of heights; someone who has been known to freeze up completely when walking close to an edge.

But also, someone determined to lay to rest a few ghosts by completing a climb to the top of a crag.

I'd say he did pretty well, wouldn't you?

I even think I see the hint of a smile!

Four routes climbed in all; gradually increasing in height!

Good job :)