stratigraphic problem.

[terapoza]

Hi. Around year ago I was exploring the area around Lough Hackett 20 km north from Galway. I found few fossils on the shore with much different fauna than typical late Visean fauna in Co. Galway. The main problem here is stratigraphy. It's similar to british Avon group of Mendips. I think all of them are Tournaisian. 

Fig1. Large piece of iron-stained black crinoidal limestone.

 

 

Edited December 19, 2017 by terapoza

[terapoza]

Fig 2. Bryozoa Bed piece.

 

[terapoza]

Fig 3. Absolutelly no idea what could it be. looks a bit like recent Lekanespharea isopod.

 

[terapoza]

other view and more stems plus one Rugosa

[TqB]

Hi, I don't think there's anything easily diagnostic there, I've seen very similar material from the upper Visean (Brigantian) of NE England.

 

I suspect the third one is a productid brachiopod with a few spine bases and prominent growth lines making it look like segments, something like Antiquatonia.

[Tidgy's Dad]

I agree. 

The British Lower Carboniferous is zoned based on either microfossils or goniatites, and corals, sometimes by brachiopod - coral assemblages. 

Nothing diagnostic in these pieces that i can see.

[terapoza]

Well. I ve never found such a big stems in the quarry and on the seashore.those are more than 1 cm in diameter. Usually I find 0,5 cm max. If it is Visean , is it possible that they were living on the different depths of the sea? Also my pictures are very bad quality because today is very bad light. I had one Leptagonia sp. From this site but lost it somewhere.

[TqB]

A different environment for the crinoids is entirely possible - you can even get get lenses of species different from the indigenous ones carried by mud slides down subterranean slopes.

 

At one Brigantian site I know, the crinoids can be 30mm diameter while in the same bed a few miles away they're not much more than 10mm, apparently the same species though it's hard to be sure.

[terapoza]

Thanks. I will leave this subject for now until I will go again to this location and find more specimens.

[Ernest H. Williams, Jr.]

I do not think it is an isopod.

[Coco]

Hi,

 

Can you explain why ?

 

Coco