Hunting at Malahide Beach

[Max-fossils]

Hi everyone!

 

During the X-Mas/New Year holidays my family and I went to Dublin (Ireland) to celebrate the New Year there (we don't enjoy NYE in The Hague much lol). Obviously, seeing opportunity to go hunt at a new location, I did some googling around and found an accessible location not far away from Dublin: Malahide Beach. LINK

It's a Carboniferous location, an age that I'd never hunted before and had very few fossils of, so I was looking forward to it.

 

We got there in the early afternoon and started looking for stuff immediately. The spot where we arrived didn't have any of the rocks that I was expecting, so we couldn't find any of the Carboniferous fossils just yet. However I noticed some small dark-grey cliffs further along the beach, so we decided to head there by walking along the coastline where there were a lot of shells to be found. While most of them are definitely modern, some of them remind me of the fossil specimens that are found in Zeeland (namely some of the Arctica islandica fragments). Here's our shell haul of the day:

I don't think any of them are actually fossilized, but I'll do some research just to make sure. 

From approximately left to right, we have: Pecten maximus, Nucella lapillus, Dosinia exoleta (?), Euspira catena, Spisula solida, Cerastoderma edule, Gari fervensis, Aequipecten opercularis, Scrobicularia plana, Mimachlamys varia, Ostrea edulis, Lutraria lutraria, Zirfaea crispata, Acanthocardia tuberculata, Arctica islandica, Anomia ephippium, Buccinum undatum, and some kind of fish bone (skull piece?). I was particularly happy with the Gari fervensis, I have a bit of a soft spot for that species  

As we were collecting shells the sun was quickly setting on us, so at some point we decided to hurry up if we wanted to actually get to the fossiliferous spot of the beach. We got there when it was already getting kinda dark...

[Max-fossils]

Here's the view looking back where we came from. 

 

Sorry for the blurry location pictures... the sun had essentially already set by now, so there wasn't much light left to make nice photos of the spot. 

[Max-fossils]

Some in-situ pictures:

Some kind of fossil in a big block of stone (brachiopod? Perhaps maybe some kind of arthropod?). The block was way too big to bring home and we didn't have any tools to extract it...

[Max-fossils]

A cross-section of a brachiopod

[Max-fossils]

After a bit of hunting, it was starting to get very cold, and there just wasn't enough light left to do some good hunting, so we decided to call it a day. We found a few small pieces with some fossils on them, but only one specimen was actually a cool find: a beautiful coral colony found by my mom  

So here are our fossil finds of the day. I'm not very good with IDing these worn inverts in matrix, so feel free to correct me if I'm wrong. 

The fossils here are from:

Quote

The coast around Malahide is composed of rocks from the Malahide Formation of the Fingal group of rocks, which were formed approximately 348mya during the Courceyan Stage (Tournaisian stage) of the Dinantian (Lower Carboniferous).

 

The left block has some very worn fossils (I think some crinoid columnals and a long white thing); they're not very showy in real life, and the picture makes it worse too...

The top block has a wide array of little specks and things that I think are mostly small bryozoans and crinoid columnal fragments.

The right block has a bunch of small crinoid columnals and some Fenestrella-like bryozoans. 

[Max-fossils]

I think that the thing in that left block is perhaps an orthoconic nautiloid of some kind? Not sure at all...

The right block seems to show the cross-section of a spiriferid brachiopod. 

[Max-fossils]

And here is the best find of the day, a cool coral (?) colony that is definitely more showy than the other specimens! The erosion nicely revealed one side of the block. 

 

So overall the finds were not very impressive, I don't think I found anything exceptional.

But it was still nice to be out and do some fossil (and shell!) hunting at a new location! 

[Max-fossils]

By the way, on our way back we came across some tennis courts, and I'm almost certain that those were the tennis courts described in the website I've linked in my top post. So I think we were probably not exactly at the spot that was recommended, and perhaps we would have found more if we had gone here. Taking the image from the website, I've shown in red the area where I think we were hunting (where you can see the little cliffs I mentioned), so as to give some reference as to where we were specifically. 

 

Anyways, I hope you enjoyed this small trip report, and thanks for reading it!

 

Happy hunting,

 

Max

[Tidgy's Dad]

Nice report, Max. 

Finding decent specimens in these Lower Carboniferous limestones can take a bit of doing but your coral, a phaceloid tabulate form such as Syringopora is quite nice.  

Most of the other pieces seem to be fragments of crinoid stems and ossicles including your 'nautiloid', I'm afraid. 

These rocks are often referred to as crinoidal limestones due to the high percentage of crionoid bits found in them, sometimes the whole rock seems to have been formed from broken up crinoids. 

[Max-fossils]

2 hours ago, Tidgy's Dad said:

Nice report, Max. 

Finding decent specimens in these Lower Carboniferous limestones can take a bit of doing but your coral, a phaceloid tabulate form such as Syringopora. 

Most of the other pieces seem to be fragments of crinoid stems and ossicles including your 'nautiloid', I'm afraid. 

These rocks are often referred to as crinoidal limestones due to the high percentage of crionoid bits found in them, sometimes the whole rock seems t have been formed from broken up crinoids. 

Well we can clearly see that you know your stuff when it comes to the Carboniferous! Thanks a lot for all the info. 

I'm not surprised that the 'nautiloid' is a crinoid stem, that was actually my first guess, but seeing that it looked a bit different from the other specimens I thought it could potentially be something else. Oh well, thanks anyways for the IDs  

[Ludwigia]

@Max-fossils Thanks for posting. This brings back nice memories, since I also visited this beach 5 years ago. I followed the instructions in the book "Classic Geology in Europe 6 - Leinster" from Chris Stillman & George Sevastopulo, entered the beach below Robbswall Castle and moved slightly southward where the Malahide Limestone Formation was quite fossiliferous, mostly with colonies of Syringopora sp. corals and the odd Hippocardia herculea bivalve. Below are views of the site to the south and north, some in situ corals and a couple of finds, which needed a good bit of hammering to be extracted.

 

 

 

[Monica]

Nice corals, gentlemen! 

[Max-fossils]

On 1/31/2020 at 11:27 AM, Monica said:

Nice corals, gentlemen! 

Thanks Monica  

 

 

@Ludwigia well wow, that's an impressive way to 1-up me  

Your finds are amazing! I don't think we were at exactly the same spot, your location looks a little different than mine (you might have been a few hundred meters further or so), unless the spot changed a lot since then. I read that it wasn't allowed to hammer the rock because it was an ASSI site, so I didn't think of bringing any tools with me. I guess that may have been a mistake then! Well done on your hunt, you did MUCH better than I did.