This EarthCache takes you to a small waterfall above the hamlet of Cray in Upper Wharfedale. The rock forming the waterfall is limestone, which is a sedimentary rock. There are other EarthCaches which describe limestone, in the region, we are here to look specifically for a type of fossil coral. You may find it interesting to visit my other EarthCaches on this subject in the Yorkshire Dales, these are : Fossil Colony... and Pen-y-Ghent Corals.... .
We are here to look for examples of a type of a rugosa coral known as Dibunophyllum bipartitum. Some corals formed colonies, but this was a type of solitary coral fossil. It was known as a type of horn coral, in that it appeared to look like a cow horn, with its pointy end secured into the sea floor, as it grew it formed ridges known as septa, and at times these can be seen ,stacked atop each other. The end of this type of coral fossil, tends to appear like a series of radiating lines, this was known as the calice, and it is from here that the feeding tentacles emerged. Some type sof horn coral grew very large, and it is recorded that another type Siphonophrentis giganteas may have reached 6 feet in length. So what are we looking out for here, well, there is one layer of limestone near the bottom of the waterfall (there is no need to enter the small gorge of the waterfall), that have some peculiar white lines on it, these are the fossils that you need to look out for. Now if there has not been a lot of rain, there may be a muddy sediment covering the limestone, so you will need to wipe away the sediment. If the watercourse is completely dry, then I recommed, using taking some water, as when the water is rubbed over the rock, like magic the fossils appear.
BE AWARE THAT IF THE WATERFALL IS IN SPATE YOU WILL NOT BE SAFE TO APPROACH THE LOCATION. IT IS SLIPPY UNDERFOOT, AND YOU MAY GET WET.
This being an EarthCache, in order to log it, I ask that you complete the below tasks. Please send the answers to me, and do not include them in your log. You can send them to me by using the message facility or email, both of which can be found by looking at my profile.
1. Please find the Dibunophyllum bipartitum fossils, please tell me what colour the limestone is where you have found them. Please do not just answer grey, as the limetsone is different colours depending where on the waterfall you are.
2. Please measure the length of the longest Dibunophyllum bipartitum fossil, how long is it in cm?
3. How wide is it in cm?
4. How many long Dibunophyllum bipartitum fossils are there in this section of the waterfall?
5. Please measure how the distance between the septa that you can see in one of the long fossils, what is it in cm?
6. The Dibunophyllum bipartitum fossils can only be seen in one section of the waterfall, why is this?