Any geology enthusiasts in house?

dr gonzo

Hey gang, I'm trying to do a very basic study of the possible source locations of a particular geology in Ireland, however I'm just finding the GSI website absolutely impenetrable. Can anyone give me some tips, or ever other ways of doing this, because it is one specific geology I'm after and GSI dont seem to cater for questions like that.

Cheers all!

Wibbs

What's the particular geology in question Dr G?

dr gonzo

Wibbs wrote: »

What's the particular geology in question Dr G?

As it turns out I've managed to knock up a bit of a workaround in QGIS but still have a bit of work to do to get to proper grips with this. Basically I'm looking at Dolerite (Dolerite axes in particular) and obviously the first step in studying wider issues is to see where they could even get it from in the first place :pac:

Interesting project but new ground for me as regards the purer geology side of it, so I thought I would throw the net out here and see if any of my capable boards colleagues had any ideas!

slowburner

Dr. G, I have to agree with you about the GSI website - the term labyrinthine comes to mind.
That said, the information is probably there, somewhere under the overburden, but it might be better and quicker to contact them directly.

Wibbs

dr gonzo wrote: »

Basically I'm looking at Dolerite (Dolerite axes in particular) and obviously the first step in studying wider issues is to see where they could even get it from in the first place :pac:

Interesting project but new ground for me as regards the purer geology side of it, so I thought I would throw the net out here and see if any of my capable boards colleagues had any ideas!

Well bear in mind I'm running on what passes for my memory here. AFAIR Dolerite is a basaltic type rock, but one with a more formed crystalline structure? Hence it would be good for axes and tools in general. In ireland I'd be thinking the basaltic outcrops up in the north of the island. Giant's causeway neck of the woods as slightly unusual conditions were around at various times. There are quite a few basaltic outcrops down south so maybe there are outcrops down here too? Maybe even beneath the Irish sea there are outcrops brought to land by wave action. For years I was wondering how our ancestors made flint tools, when high quality flint was pretty much restricted to a small outcrop near Lough Neagh. Many moons ago I was walkin beaches on the south east Wexford coast and noticed quite the number of flint/higher quality chert nodules on the beach and the local geology wouldn't suggest that kinda thing.

slowburner

Aren't these flint 'erratics'/deposits the result of tidal action along the east coast?
AFAIR the primary source along the east coast (geologically) is a lode somewhere near the Isle of Man. Open to correction on this.
Flint deposits are widespread up the west coast of Scotland, Wales and the Irish east coast.
No doubt meso/neolithic folks found coastal districts agreeable, as much for the plentiful flint supply and food resources as the disincentive to challenge the foreboding native woodland, and all that challenge entailed.
A stroll along some of the east coast pebble beaches will throw up many, many lumps of flint.
Very many of these show signs of possible working, although water rolling would make a positive identification impossible.
If you found these shattered pebbles anywhere else, you'd be wide eyed. Here you'd scarcely give them a second glance.
I think every one of them needs closer scrutiny.
I have no doubt that rising sea levels, and massive coastal erosion will reveal significant spreads of flint artefacts.
It would be an awful pity if they were missed because they mingled with the tumultuous tideline, and were forever lost.
Mitchell noted several spreads, mostly cores and debitage, along the east coast.
Some of these spreads were 2km inland. Others have already been lost to coastal erosion.

Apologies for the diversion Dr. G, dolerite is an interesting resource - where did you come across it?

slowburner

Probably not much good to you (I just find some of this particular author's writings enjoyable to read).

G.H. Kinahan. Manual of the Geology of Ireland. 1878.
(pp.156 - ).

'The Irish Tertiary rocks of Miocene age occur only in the province of Ulster'
I think this may be the rock classification encompassing dolerite.
Kinahan lists many of the principal Ulster dolerite beds - you'll find them in the index.

http://archive.org/stream/manualofgeologyo00kina#page/n7/mode/2up

Here's a more recent reference to dolemite outside Ulster - Doon Hill near Clifden, Co. Galway.

http://www.jstor.org/discover/10.2307/20494386?uid=3738232&uid=2129&uid=2&uid=70&uid=4&sid=21101688921931

pueblo

OP, Not sure if this is of help or not but the Irish Stone Axe Project Monograph I (Gabriel Cooney & Stephen Mandal) has some very interesting material and does make some mention of gabbros and dolerite and their potential sources along with a map showing distribution of dolerite axes.

If you don't have easy access and would like a look I would be happy to lend it to you.

dr gonzo

pueblo wrote: »

OP, Not sure if this is of help or not but the Irish Stone Axe Project Monograph I (Gabriel Cooney & Stephen Mandal) has some very interesting material and does make some mention of gabbros and dolerite and their potential sources along with a map showing distribution of dolerite axes.

If you don't have easy access and would like a look I would be happy to lend it to you.

I know it well, I work for ISAP but appreciate the input and the offer Pueblo!

dr gonzo

OK! Apologies gang, I was writing up a proposal over the last few days and I've just now had a chance to actually read the comments!

As I mentioned to Pueblo I'm involved in the Irish Stone Axe Project in UCD, and specifically, Prof. Gabriel Cooney is my supervisor in both project and thesis. After some chats dolerite axes were seen as a topic worthy of more research but also one that was feasible for a masters thesis, and there is pretty much the whole story

They are actually very interesting. 21500 axes in Ireland, of which half are porcellanite. Dolerite then makes up about 5% of the rest at 502, and they really havent been touched on too much so it should be good!

Wibbs wrote: »

For years I was wondering how our ancestors made flint tools, when high quality flint was pretty much restricted to a small outcrop near Lough Neagh.

Dont forget about trade and transmission Also as a knapper myself who has had a good amount of experience with Antrim flint I have to say that high quality is being quite generous.


Incidentally, how did you guys come into archaeology? Would I be right in assuming that you have a geology background Wibbs?

Wibbs

dr gonzo wrote: »

They are actually very interesting. 21500 axes in Ireland, of which half are porcellanite. Dolerite then makes up about 5% of the rest at 502, and they really havent been touched on too much so it should be good!

Sounds like a good area to explore alright. 20 odd thousand axes on record? Wow that's a lot.

Dont forget about trade and transmission

True enough. One of the killer apps of modern humanity. With previous folks, with the odd erratic all their materials are "local", usually within a 30 mile radius. We might have been called Homo Negotium.

Also as a knapper myself who has had a good amount of experience with Antrim flint I have to say that high quality is being quite generous.

Oh really? Not so hot? Some of the stuff I picked up on beaches along the south coast wasn't too bad. Nothing like the quality of good British, Spanish and French flint I've seen mind you. Some of the French stuff is like glass. Knapping is hard. For me anyway. Back in the day I could rustle up a passable biface in a pinch. Soft percussion and pressure stuff to rustle up blades I found relatively easy. Wouldn't win any prizes mind. By far the hardest I found was the earlier Neandertal Levallois technique. Core prep was really difficult and then you had pretty much one shot to get the blade/point right. I've examples of cores where it's clear they sprung loads of tools off the one block. In one example the last flake he sprung shows amazing skill with the material. There's a crappy inclusion in the material and he misses it by mm. One hard hammer strike. :eek:

I've noticed with the interweb and explosion of interest in knapping you see some amazing tools being made. The American knappers can knock out some spectacular near art level stuff, but very few try Levallois stuff. Theres one chap on youtube who's very good, but so far he seems to be at the circular scraper level, no points.

Aside... one thing that always struck me(ouch:)) was how noisy knapping is. For hunter gatherers every animal in the area must have thought "oh oh humans".

Incidentally, how did you guys come into archaeology? Would I be right in assuming that you have a geology background Wibbs?

I'm afraid the only geology background I have are holiday snaps of me standing in front of mountains. The only bits and pieces of knowledge I might have comes from being mad into fossil collecting as a kid. Archaeology just an amateur curiousity/interest really.

dr gonzo

Wibbs wrote: »

Sounds like a good area to explore alright. 20 odd thousand axes on record? Wow that's a lot.

Indeed! And more being found fairly regularly. Incredibly interesting to see different styles, level of completion, primary production method etc.

Wibbs wrote: »

Oh really? Not so hot? Some of the stuff I picked up on beaches along the south coast wasn't too bad. Nothing like the quality of good British, Spanish and French flint I've seen mind you. Some of the French stuff is like glass.

Well, now its probably me being a bit unfair. It knaps reasonably well, but certainly takes a little more power (skill even) to get what you want out of them. Generally filled with chalk too. As you say, the British and european flint is stunning by comparison.

Wibbs wrote: »

I've noticed with the interweb and explosion of interest in knapping you see some amazing tools being made. The American knappers can knock out some spectacular near art level stuff, but very few try Levallois stuff. Theres one chap on youtube who's very good, but so far he seems to be at the circular scraper level, no points.

Aside... one thing that always struck me(ouch:)) was how noisy knapping is. For hunter gatherers every animal in the area must have thought "oh oh humans".

Haha, I cant say noise levels are something I've ever considered about this before but youre dead right, you better have all your tools ready to go beforehand otherwise you probably aint gonna find any animals!

The stuff american knappers are coming out with is insane. In fact, in certain cases, their skill goes well beyond that of the average stone age knappers. Obviously theres a few caveats to that; there are certainly objects that cannot be reproduced anymore. More to the point American knappers, like you hint at Wibbs, are not really that concerned with tackling genuine archaeological designs. They end up producing impressive, but unique, objects for themselves. John Whittaker's book shows a lot of good examples of this.

Wibbs

dr gonzo wrote: »

Indeed! And more being found fairly regularly.

Makes me feel bad. Many hours as a kid staring at the ground and nada on that score. No polished axes, yet on various fortnight holliers in Spain and France, with the sufferance of my parents I found the odd Neandertal stuff. Just not cut out for the meso and neolithic. I'd probably walk right by Newgrange, "looks like a boring hill to me"

Incredibly interesting to see different styles, level of completion, primary production method etc.

Yea! How cool is that, to see all that in sequence. Were there regional "styles" involved?

Well, now its probably me being a bit unfair. It knaps reasonably well, but certainly takes a little more power (skill even) to get what you want out of them. Generally filled with chalk too. As you say, the British and european flint is stunning by comparison.

+1, they defo had an abundance of riches going back nigh on a million years. No wonder they've got multiple humans going on. Then again we've always been a "make do" and innovative lot. On Crete much to their surprise they've found stone tools cooked up from the local quartzite dating back a couple of hundred thousand years.

Haha, I cant say noise levels are something I've ever considered about this before but youre dead right, you better have all your tools ready to go beforehand otherwise you probably aint gonna find any animals!

Only deaf ones

The stuff american knappers are coming out with is insane. In fact, in certain cases, their skill goes well beyond that of the average stone age knappers.

Very much so. Then again I've noticed quite the bit of skill variability in stuff I've seen/collected. Makes sense, even today some of us are better than others at various tasks. Every so often you do see a real "artist" at work, where it goes beyond a "simple tool". Pride is probably not a recent thing.

Obviously theres a few caveats to that; there are certainly objects that cannot be reproduced anymore. More to the point American knappers, like you hint at Wibbs, are not really that concerned with tackling genuine archaeological designs. They end up producing impressive, but unique, objects for themselves. John Whittaker's book shows a lot of good examples of this.

+1 Just my take now, but I reckon soft percussion and especially pressure flake work is "easier" for the modern mind. It's more controllable and gives cooler results up front with less practice, compared to hard hammer work of various kinds. Funny enough where I've seen more "genuine" archaeological techniques at play is on ebay with guys selling fakes of Mousterian/Levallois and other stuff.

slowburner

This (1868) image is from the Du Noyer collection of the British Geological Survey. (A website well worth having a nose around).
Scrabo Hill in County Down, was a source of dolerite according to Kinahan (op. cit).
Quite often, the lines between geology and archaeology were blurred by these 'gentlemen scientists'.
It seems to be a different pit to the better known and larger quarry worked for building stone since the C12th. Might the gentleman have been observing the remains of an early operation?