I was asked very nicely to set up this earthcache for the 2023 New Years Resolution event, held in Kilfinane in January 2023. Payment of coffee, some spiced beef and a good ole tour of the town with some geochat thrown in were made to me.
This Earthcache
A very simple earthcache across two stages in the lovely town of Kilfinane, bringing you to a very nice little roadside sculpture and showing you a set of fossils in the town square. I made it two stages partly because there is an interesting comparison to be made between the two sites and partly to annoy people who come to this part of the world wanting to clear every single icon off their map but yet who hate earthcaches and wish they didn't exist.
The millstone on the front of the sculpture. Quite impressive!
Limestone & Fossils
Limestone is a sedimentary rock made almost entirely of fossils. Fossils are the remains of ancient plants and animals, like an imprint in a rock or actual bones and shells that have turned into rock. Fossils are found in sedimentary rocks and hold the clues to life on Earth long ago. Limestone fossils are mostly brachiopods, ocean animals that became extinct millions of years ago. Brachiopods had shells and were found in large groups on the shallow ocean floor. They were like the clams and oysters we know today.
Over time, the shells and skeletons of tiny organisms like brachiopods built up on the seafloor. These shells and skeletons were made of the mineral calcite. The layers of calcite fragments pressed down on top of each other. All the water was squeezed out, and the layers of calcite fragments were cemented into rock. What's left was limestone, made of calcite crystals. Of course, there were many of the original shells left, too.
Some limestone contains loads and loads of fossils, other limestones - not so many. But Irish limestone is very interesting in general. If you start looking, you will see not just brachiopods, but other animals such as gastropods (snails), corals (both solitary and colonial), ammonoids, bivalves and crinoids amongst others. New species are still being discovered today - an Irish geologist discovered a new species of brittlestar in 2017 in a limestone sample.
Questions
Answer the following questions and send them to me via the Messenger or via an email. Feel free to log the cache before you send them, but please send them within a reasonable timeframe. Sending no answers may result in your log being deleted, with fair warning. Optional questions are just that, optional, they are for the earthcache nuts (like me) who enjoy looking that bit more closely.
Stage 1 (posted co-ordinates): At the given co-ordinates you will see a sign for Cill Fionáin. Admire it and have a look at the plinth it is standing on.
- Read the description and tell me how these fossils got here.
- What is the size of the largest fossil?
- What shape do you think these animals were in 3D?
- Turn around and look at the notice board. What type of stone does it say the millstones were often made out of?
- Do you think the plinth is made of this type of stone? Why?
- Optional: Identify what fossil types you see here.
Stage 2 (Waypoint at N 52° 21.511' W 8° 28.196'): Stop moaning and go to Stage 2. You will be standing on the steps.
- Are the fossils in these steps the same as those at Stage 1?
- Do you see any plant fossils here, eg: Coral? Describe them if so.
- Optional: What geological periods do you think the rocks at both stages are from?
- Optional: Are they from the same quarry?
In case I have long been confined to history myself and this earthcache lives on in geological time... the New Years Resolution Event is an annual get-together of Irish cachers that involves one or two nights in a nice hotel, lots of drinks with some good food as well as the main looped walk. It always involves plenty of caches... well.. sending various kids to get caches while we all stay on the path nattering. It is always the one event that I would move heaven and earth to get to. That one annual meetup that you just have to be at. It would always bring cachers out of the woodwork that you don't get to see on any other occasion. At the time of writing, I have attended 10, all those held between 2012 and 2022.