The field trip consisted of 5 days of mapping the slopes of Ben Hiant as well as a day doing something of a guided tour of the peninsula as a whole. What follows are photos of some of the more interesting features we observed, as well as brief explanations of their geological context.

Radially Jointed Vitrophyre

Here we can see a lovely radially jointed vitrophyre outcrop on the side of a steep gulley. The jointing nicely illustrates the intrusive relationship with the surrounding Breccia.

Annotated Vitrophyre

The vitrophyre outcrops in this area are part of a group of inclined sheet intrusions which are part of the British-Irish Paleogene Igneous Province (or whatever the current politically correct name is, I favour the North-Western European Archipelago Paleogene Igneous Province personally). Other inclined sheets of varying crystal size from glass up to Dolerite abound in the area, as cone sheets emanating out from the intrusive centres.

Dolerite Sheet on Ben Hiant

Cone Sheets on the Shore at Kilchoan

Xenoliths in Dolerite Sheet

Closer to the middle of one of the intrusive centres (Centre 3) is The Great Eucrite  – a striking ring of Gabbroic ridges surrounding the inner parts of the complex.

View Northwards from the heart of Centre 3 - The Ridge is the Great Eucrite

The rocks towards the centre get steadily more silicic in composition, with Tonalites and then a Quartz Monzonite outcrop in the very centre. The current understanding of this structure is that it represents an uplifted and eroded Lopolith (not, as originally thought, a ring dyke).

Another location we visited was the Gabbros of Sanna Bay. These are a sequence of coarse grained basic rocks which show distinct mineralogical layering, both modal and phase layering.

Layered Igneous Intrusion

Layered Gabbros

Interestingly some of these units also show evidence of sedimentary structures such as normally graded bedding:

Normally Graded Bedding

Lens-Like Structures and Undulose Bedding (With my Cousin Karen for scale)

These are a classic layered intrusion similar to the grander examples found elsewhere such as Skaergaard or the Bushveld. We spent a fair bit of time studying these in the first semester of third year, so it was nice to see them in the field.

Another location visited was a delightful example of magma mixing at Eilean Carrach, opposite the Lighthouse on the point of Ardnamurchan.

Magma Mixing

For those of you who have this trip to look forward to (i.e. potential/current Glasgow Uni Earth Science Undergraduates) then expect to spend a significant amount of your evenings doing this:

Working on a Report at 3am

But also some of this as well:

Work Hard, Play Hard

The trip also provides no end of opportunities for posing dramatically on hillsides:

Ben Hiant

(and beaches)

Beach at Eilean Carrach

Further Reading

Gribble, CD (Ed). Ardnamurchan: a guide to geological excursions. 1976. Edinburgh Geological Society. – Nice book, good descriptions and a fold out map. Interpretations are a bit out of date however.

McBirney, A. Igneous Petrology. Third Edition. 2007. Jones and Bartlett. – Brilliant Section on Layered Igneous Intrusions, I highly recommend it.

]]> http://bobjamieson.net/2010/04/27/ardnamurchan-2010/feed/ 0 http://bobjamieson.net/2010/02/17/edinburgh-arthurs-seat/ http://bobjamieson.net/2010/02/17/edinburgh-arthurs-seat/#comments Wed, 17 Feb 2010 22:46:07 +0000 Bob http://bobjamieson.net/?p=386 On Saturday just past I popped over to Edinburgh for my once-every-two-or-so-months-sometimes-longer catch up with Jono. Since the weather was fairly nice, and it’s always good to do something a bit different beyond just get lunch or a coffee, we decided that we would go up Arthur’s Seat. Katie was also in town to visit Jono, so we all spent a rather pleasant afternoon scrambling up hills and eating excellent Curry. In fact I’d say that the Mosque Kitchen is actually one of the most important locations to visit on this excursion.

We started out from the North end of Holyrood park, next to Dynamic Earth and the Parliament Building, climbing up first towards St. Anthony’s Chapel. We stopped on the ledge just below the chapel where you can find some carbonised plant remains. I was almost entirely certain that I took a photo of these, but judging by the contents of my memory card I apparently didn’t. The view down towards St. Margaret’s Loch is pretty however:

St. Margaret's Loch

View back Towards Edinburgh

From St. Anthony’s Chapel you can see back the way we climbed (see above). At this point we’re already up onto the Basaltic Lavas which make up Whinny Hill. From here we continued climbing upwards, eventually transitioning from the Lavas to some Agglomerates. The top of Arthur’s seat is a mixture of Vent Breccias as well as porphyritic Basalts.

Foreground: Vent Breccia | Middle Distance: Dunsapie Hill (Basalt) | Far Distance: North Berwick

Posing for Photos halfway up

View out from the Top (Basalt), over Salisbury Crags (Basic Sill). Note Castle Rock in the distance (Basaltic Plug/Crag and Tail)

At the top we waited for the large group of tourists to get out of the way, then stopped for a break at the trig point. At this point Jono decided to regale us with the delightful tale of a group of his friends who apparently decided to strip-off up there on a foggy day. This is a fairly typical Jono story.

Jono and Katie at the Top (view North towards the Firth of Forth)

We then continued westwards, going down the hard way. Here’s the slightly terrifying view back towards the top:

View Back up (Foreground is mostly Agglomerate, Peak is Basaltic)

Jono seemed keen for some Quaternary Geology, so being the nerd I am I decided to take them down to the Roche Moutonnée which is nicely exposed as a road cutting on Queen’s Drive. My memory proved accurate, and we actually scrambled down the hillside basically right on top of it, startling a group of Rabbits. Whilst coming down we once again stopped for a quick break, and Jono took what has become one of my favourite photos of me:

Perched on an Outcrop

I failed to get a good photo of the Roche Moutonnée, but if you’re dead keen I’m sure you can find one elsewhere. Before heading down for lunch I dragged the pair to one last stop: Hutton’s Section. Then, on the way back round we also briefly passed Samson’s Ribs – an example of lovely columnar jointing.

Jono's (Hutton's) Section

Samson's Ribs

Holyrood Park is a great day out if you’re wanting to get out into the field and clamber over some rocks. We only spent about 2 and a half hours there (so as not to bore the non-geologists too much), and barely scratched the surface of what you can see there – there’s heaps of other things to look at. So if you’re ever in Edinburgh and have a bit of free time, it’s a great place to go. It helps that it’s only 10 minutes away from the centre of the city.

The usual drill with regards to photos, higher resolution examples can be found on my flickr page (until they get knocked off by new ones).

Recommended Reading:

Craig, G.Y. and Duff, P. McL. D. (Eds). (1975). The Geology of the Lothians and South East Scotland: An Excursion Guide. Scottish Academic Press, Edinburgh. [This is a great book, but I can't imagine it's particularly easy to find copies of].

University of Edinburgh Field Trip Info – Really fantastic summary of what’s going on with the geology of the area. I highly recommend it.

University Field Trips

(8/3) – Portencross

More Old Red Sandstone :(

(11/3) – Rosneath

According to our timetable it’s a Structure class, which probably means lots and lots of Stereonets going by the term so far. Map says the rocks are Dalradian, so that’s probably a good bet.

(6/4 – 14/4) – Ardnamurchan

Week long residential field trip. Looks to be mostly mapping I think.

(17/4 – 24/4) – Mull/Oban

Week Long residential field trip visiting Oban, Kerrera and Mull.

Summer Mapping (Late may/Early June) – Elie, Fife

At least two (probably 3) weeks of field mapping along the Fife Coast. Individual project which makes up a pretty large chunk of my final degree mark (9%)

Other Places I Want to Go

Salisbury Crags – Edinburgh
Just a thing to do one afternoon with Jono or someone. They’re easily accessible and always a bit of a fun day out.

Loch Lomond – Always a good day out, lots to do and see. Might go back to the Highland Border Complex, maybe look at some Quaternary stuff. I dunno. I want to climb Ben Lomond at some point, probably during the Summer.

Some Other Munroes – Not sure which ones yet, but Hazel fancies a trip and has a car, so most of the country is open to us.

Some Local Quarries – Taking a look at some local fossils and minerals
Carboniferous Corals at Trearne
Prehnite and some other secondary minerals at Loanhead or Boyleston

Be sure to tell the bewildered looking German PhD student standing next to it that Bob says hi. That should baffle Heiko entertainingly.

Last Thursday the class (the entire honours class this time, not just Limnology Students [the few, the brave, the mighty]) headed back up to Loch Lomond to the hamlet of Balmaha. This tiny little village sits practically on top of the Highland Border Complex / Boundary Fault, making it our third visit to this Terrane Boundary (the previous being Arran and Stonehaven).

The purpose of the trip was to get us thinking about relationships between Terranes, the evidence for there actually being different Terranes on either side of the fault, and to give us something to think about for our Stratigraphy essay (due in on Monday – yes, I’m procrastinating).

The trip was pretty interesting, if fairly brief. We only really looked at 3 localities; part of the Complex itself, some Upper Devonian ORS Conglomerate and an earlier Lower Devonian ORS Conglomerate. We didn’t go far enough North to cross over onto the Dalradian metasediments.

The Outcrop of the Highland Border Complex consisted of a Serpentinite outcrop in the forest, and some poorly exposed Breccia on the beach, containing clasts of Serpentinite and Gabbro (Cherts, Dolomite, Pillow Lava and Trondjhemite clasts can supposedly be found if you hunt hard enough, but the exposure is poor). If you fancy trying to track this spot down yourself I highly recommend this leaflet [pdf] (location 5), produced by the Strathclyde RIGS group (Part of the Geological Society of Glasgow).

Serpentinite Clast in Breccia

Unfortunately this was the point in the day where the Scottish Winter began to make its presence known. Remember those nice sunny photos last time? It wasn’t like that:

Loch Lomond in the Rain

The first of the two Conglomerate outcrops we looked at on our way south (location 4 in the RIGS leaflet) was the Late Devonian one. It’s a fairly typical ORS Conglomerate, as previously seen on Arran, of mostly metamorphic clasts in a red sandstone matrix. It probably represents an alluvial fan deposit coming off Dalradian Highlands.

ORS Conglomerate outcropping on the Shore

The Second Conglomerate outcrop (1 and 2 on the leaflet) is a younger outcrop. On first glance it appears roughly similar, being part of the ORS unit, however upon closer examination the clasts are of an entirely different origin. We were seeing Quartzites and various igneous clasts rather than the vein quartz and psammites from the Dalradian. A textural difference is noticeable too, these are much rounder than the sub-angular clasts of the first outcrop. This would seem to indicate that in the Lower Devonian the area to the South of the HBF was not in proximity to the Dalradian rocks of the North.

Foreground: Lower Dev. Conglomerate. Background: Lomond North Basin

View Down towards the South Basin

Well that’s it for the Balmaha trip overview! It was a fun and informative trip, made all the more-so by the fact that it was taken by experts on the subject – including Tim Dempster and Brian Bluck.

For further reading on the subject try the (oft-recommended by me) field guide below:
Lawson, J.D. & Weedon, D.S. 1992. Geological Excursions around Glasgow & Girvan. Geological Society of Glasgow.

Edit: Also, the number of google search hits this is getting from what I assume are my classmates working on their essays is brilliantly high.

One of my more work-intensive third year option courses this year is Limnology. The course is just wrapping up just now and ends with a field trip to the SCENE facility at Loch Lomond, so yesterday we all got to make a nice little trip. We got extremely lucky with the weather, turning what could have been a horrible experience into a delightful day out in the countryside.

The day was divided into two halves, with half of our time spent out on the lake taking samples and measurements and the other half in the field centre labs analysing samples. My group spent the morning in the lab, studying the phytoplankton and zooplankton present in a south basin water sample, as well as performing some rudimentary water chemistry measurements.

The trip costs also included lunch, which was provided by the field centre, and it was bloody brilliant. Tomato and Pepper soup, alongside rolls with a whole range of fillings. Needless to say I stuffed myself silly.

In the afternoon we went out onto the lake on the speedboat to gather samples. My mini-group were using a Van Dorn (henceforth: Van Damme) sampler to take water samples from various depths in the lake at two different sample sites. We then filtered and extracted these samples in the lab on Friday to measure chlorophyll concentrations. Other members of our groups took Temperature, DOC and Turbidity readings as well as taking some sediment samples.

The trip workload wasn’t particularly heavy (a shocking change from the rest of the course so far) so we basically had a fun day out on a beautiful lake in what was probably the last really nice sunny day of the year.

My camera battery died early in the day, but below are some photos I snapped on the trip (as usual, there are higher res images on my flickr page):

Boat

Pier

Woods

Highland Boundary Fault

Slightly visible in the picture above is the line of the Highland Boundary Fault (Hint: Follow the Islands) and, if you look closely, the town of Balmaha – the location of our next field trip in 2 years time. I’m not too optimistic about the weather however.

On the Lake

Islands in the Sun

Lake

Reflections on the Water

Andy Wading

We ended the day with a group photo taken sitting on the Pier. Which of course meant that Andy had to get his feet a little bit wet…

- Finally managed to wrap up the lab work. We’re now at the data interpretation and paper writing stage, which I am almost no help with – as much of it is still well beyond me. Still, expect to see more updates on this if/when the paper is published.

Borders Trip

- Scremerston

- Eildons
In addition to popping down to the coast we also finally climbed the Eildons (after not managing it last time). Unfortunately, from a geological standpoint this wasn’t too exciting as the rock outcrops were very weathered and sparse. Still, it was a nice mornings climb.

The Largest Eildon

The largest Eildon – note the slightly stepped appearance, this is due to compositional differences in the layering of the lacolith.

Path Erosion in Progress

An Iron Age Hill Fort (believe it or not)

Northern Ireland Trip

- I ferried my way across to Northern Ireland to spend a weekend with my friend Mark. We did the usual tourist wander around Belfast and drove up to see the Giant’s Causeway, possibly the most famous geological site in the UK, and a fantastic example of Columnar Jointed Basalt.

And then we went to Bushmills distillery on the way back; which was good, but nowhere near on par with Scottish Whisky.

(sorry about the slightly poorer photo quality – forgot my digital camera, so used my iPhone)

Giant's Causeway

Causeway

Entirely Inappropriate Footwear (and columnar jointing)

As usual, more photos can be seen on my flickr page.

London Trip

- Once again I also made my annual journey down to London for Apple Campus Rep training, probably not supposed to talk too much about this online though. It was good fun though, and I got to meet lots of interesting people. If you’re in a UK Higher Education establishment I’ll once again plug the discount of up to 15% that you can get from Apple here. /shamelessplug

Up Next:

• This Months Accretionary Wedge (if I get it done before deadline).
• A couple of write ups from class field trips (after I’ve done them, and after the deadline for any work based on them).

So we decided to drive down to the beach at Scremerston, a stretch of coast in the North-East of England just south of Berwick. It’s a stretch of Carboniferous Limestones, Shales, Sandstones and some coal layers. The palaeoenvironment is basically that of a coast line; with remnants of Corals, Crinoids and Brachiopods which lived in shallow waters as well as coal swamps on land. There’s quite a lot of folding evident along the beach as well, some of which is visible on Google Maps.
We parked alongside what I think is an old coastal defence position, had lunch, then headed down to the beach to do some fossil hunting.

Gunnery Position

Since we mostly just wandered around randomly I won’t try and describe the locality in a particularly systematic fashion, instead I will attempt to highlight the various fossils and structural features that can be found in the area.

Large Brachiopods (Possibly Gigantoproductids)

Note the extremely bioclastic nature of the rock – it’s basically all shell fragments.

Trace Fossils

As previously mentioned on this blog, my palaeontology skills aren’t fantastic, but I think these are probably Gastropod trails.

Rugose Coral

Rugose Corals

Geode in Cavity

Sectioned Crinoid Stems

Crinoids are particularly abundant in this area. If you’re looking for specimens there is a fantastic bed of soft, weathered rock where you can practically pick them out with your fingers at approximately 55°43.725′ N by 1°57.072′ W.

Dipping Beds

In places large sections of strata are exposed, including (at the bottom right of this image) the occasional coal seam.

Folding

Further north up the beach are some delightful examples of folding, with various parts of the fold exposed – some showing quite complex structures.

More Folding

Fold hinge (note the extensive veining)

Me

Fold Hingeline

The dunes above the shoreline are also of interest, albeit not so much to geologists. The area is host to a wide variety of fairly rare butterflies, a couple of which I was able to photograph (rather  inexpertly).

Spot the butterfly

As usual, all of these photos are up on my flickr page here (at least until they get knocked of by new ones – I have a non-pro account).

The area is a great day out, and specimens of Brachiopods, Crinoids, Corals, trace fossils, iron nodules, geodes, folding, veining, rootlets above coal seams, and a whole lot more can all be found in a kilometre or so of coastline. You might hear more from me on this topic in the future, as I’m seriously considering it as the location for next summer’s mapping project.

Our recent trip to Girvan meant driving for at least a couple of hours. And y’all know what that means: new field trip mixtapes.

Geotrip Disc 3: Nerdcore Special

This Disc is comprised of my favourite Nerdcore tracks. Unfortunately everyone else was less of a fan. Went down well at game night though.

Name – Artist
Geekend Freakout – Nursehella
Roommate From Hell [Ice and Fire Mix] – MC Lars feat. MC Chris
Bank Holiday – The Grammar Club
Penny Arcade Theme – MC Frontalot
Nursehellamentary – Nursehella
1337ology – Beefy feat. MC Router
99 Balloon Flights [Badd Spellah Nena Remix] – The Grammar Club
Fett’s Vett – MC Chris
Goth Girls – MC Frontalot
Download This Song – MC Lars feat. Jaret Riddick
The Positronic Pimp – Futuristic Sex Robotz
Hipster Girl – MC Lars
You Can Call Me Beef – Beefy
Hey There Ophelia – MC Lars
Secrets from the Future – MC Frontalot
Arguing on the Internet – Shael Riley
Internet Relationships – MC Lars
Alternate Ending – The Grammar Club
GP – Beefy feat. MC Router

Geotrip Disc 4 :Nostalgia Pop

A disc full of silly summery pop. Great for a sunny afternoon drive.

Name – Artist
All Star – Smash Mouth
Lemonade – Wheatus
Leave Me Alone (I’m Lonely) – P!nk
Teenage Dirtbag – Wheatus
Wild Wild West – Will Smith
Shining Light – Ash
Say it Ain’t So – Weezer
William McGovern – Wheatus
Lazy Eye – Silversun Pickups
My Life Would Suck Without You – Kelly Clarkson
Get the Party Started – P!nk
Lizstomania – Phoenix
Steal My Sunshine – Len
Mmmbop – Hanson
Doctor Jones – Aqua
Brimful of Asha – Cornershop
We Used to be Friends – The Dandy Warhols
Burn Baby Burn – Ash

Next Time: The Metal Disc, The Goth Disc and the Classical Disc.

Location 1 – 55°5.18′ N 5°0.992′ W: Pillow Lavas approximately 1.5km down coast from Ballantrae.

Our first stop of the day was the furthest down the coast, away past Ballantrae. Here we parked at a graveyard and walked down through a farm with some incredibly scary cows which chased us halfway to the ocean. A short walk along the coast brought us to this:

Pillow Lavas!

A great big outcrop of pillow lavas! Not only that, but beneath our feet was an eroded surface which displayed a sectioned mass of pillows with their way-up obviously visible.

Pillow Lavas with Hammer for Scale

Other parts of the outcrop showed overturned pillows where the iron rich minerals of the basalt had been oxidised by the seawater:

Oxidised Overturned Pillows

These pillow lavas were originally deposited in the Iapetus Ocean and then obducted onto the land during the Caledonian Orogeny when the Iapetus closed at somewhere around 440-420Ma. This ophiolite is (somewhat unsurprisingly) known as the Ballantrae Complex and also includes Black Shales, Cherts, Gabbros, minor Granitoids, Serpentinite and some metamorphic rocks (Lawson et al. 1992).

Location 2 – 55° 9.82′ N 4° 56.877′ W: Varyag Monument, Lunch and Boulders.

We stopped for lunch further up the coast just shy of Lendalfoot, at the Monument to a Russian Cruiser which the Russians lost to the Japanese, took back, then got nicked by us, sold to Germany and which we then accidentally sunk in the Firth of Clyde (you can’t make this shit up!). Disrespectfully we posed for photos on the anchor.

Varyag Anchor - John and Emma

After lunch we had a nosey around on the beach to see if we could find anything exciting. The first thing we spotted was this boulder (or possibly outcrop, rather difficult to tell as it was partially buried):

Boulder

Looking closely you can see that this boulder is of mixed composition, with a finely grained rock on the top half, and a coarser grained intrusion at the bottom of the picture. You can even see the coarser grained forcing its way into a crack in the finer grained material, halfway to making a little xenolith. A third composition, even coarser grained also appears to be intruding at the bottom of the image.

We also found an interesting looking greenish boulder which Emma took back to the department and chopped up, revealing what we think is a hydrothermally altered Harzburgite:

Harzburgite (on 1cm graph paper for scale)

Also at this location we found veins of fibrous Pectolite, which I don’t have a photo of to hand, because Emma has the sample.

Location 3 – 55° 9.830′ N 4° 56.62′ W: Boathouse and Dykes. A short walk up the Coast.

Location 3 was slightly along the coast, by an old boathouse. This boathouse was propped up against a nice big dyke. This dyke also displayed an interesting mixed composition; with two distinct compositions in contact with each other. In places small dykes spread off from the main mass, the cross-cutting relationship indicating the order of the intrusions:

Mini-Dyke! (close examination shows chilled margins).

Location 4 -  55° 13′ N 4° 52′ W (Location Approximate): Walk Down coast from Car Park at South Edge of Girvan (next to old folks’ home).

Supposedly there are fossiliferous beds in this area which contain Trilobites, Brachiopods and Graptolites. We couldn’t find any of them. We did however find some excellent examples of various sedimentary and structural features:

Soft Sediment Deformation

Foreground: Faulting. Background: Folding. Emma's Pockets: Stuffed with Rocks

Emma and John (spot the desiccation cracks!)

With that we headed back up the coast to the car, stopping off to collect one more rock sample:

Granite

A nice chunk of Granite that I hammered off of a dyke (albeit a man made one. OK fine, I ‘borrowed’ it from the wall of a field).

With that, we headed back up the coast, stopping off at Troon to continue our field trip tradition of getting Fish and Chips for tea on the way home.

• Lab Work: I’m still working in the Lab, having just finished my fifth week there. The project is going really well. We’re starting to get mountains of data back from our GC runs. There are two weeks left on the project, most of which will be spent hydrolysing my esters so that we can identify the acids and alcohols present. Then, time and circumstances permitting we’re going to head over to SUERC in East Kilbride to take a look at Stable Carbon isotopes.
• Girvan Trip: Me, Emma and Emma’s mate John went on a short day trip down the coast between Ballantrae and Girvan (will be more on this later).
• Reading: I’ve got a fair bit of reading done, mostly about Zooplankton. But I also got to re-read one of my favourite books: Anathem by Neal Stephenson, and I’m currently cracking my way through The Code Book by Simon Singh.
• Gaming: Somehow we’ve spontaneously formed a new gaming group, which has let me get back into playing RPGs. We’ve had two massive gaming sessions so far; a D&D Scenario run by Chris and a WFRP game run by yours truly. We’re probably going to spin both of these off into full campaigns.
• Various Internet Nonsense: I’ve moved all my RSS feeds from Thunderbird to Google Reader, with broadly positive results. It saves a lot of time reading stuff on my iPhone while on the subway rather than sitting down to catch up on the days events in a oner. I’ve also started using Mendeley today. I haven’t really used the networking aspect of it at all (I think I prefer LinkedIn still at this point), but the desktop application is fantastic for organising the alarmingly large number of papers I need to read. Highly recommend checking it out.

So yeah, that’s what I’ve been up to. A full post on our Girvan excursion will follow in a couple of days, and a wrap up post about working in the lab will appear in a couple of weeks.

In the meantime, here are some pictures:

My Workspace in the Lab

My fume hood, work in progress samples and lab book. Also visible is one of the rotary evaporators.

Extracts

The extracts from the first 11 samples + blank (one of the samples isn’t shown) before drying them down to weigh the dry mass. The brilliant orange colours are an unusual sight in a geochemistry lab. The bright orange colours of samples 50 and 51 are from Calanus Hyperboreus.

It was a really good first week, I’ve learnt a lot and it has been pretty enjoyable. The next 6 weeks promise to be just as interesting, if not more so.

“So July’s topic is about your inspiration to enter geoscience. Was it a fantastic mentor? Watching your geologist parents growing up? A great teacher, or an exciting intro field trip? How did it happen?”

This is a difficult question for me to answer; mostly because of the way my decision making process (on the larger decisions at least) seems to work. I go from having a decision to make (e.g. at around 16 or 17 trying to decide what to do at university) to having made the decision without being entirely conscious of the process I’ve gone through to make it.

A whole load of little factors combine to result in a decision being made – the major ones are listed below:

• Local Geology: As I’ve shown in some other posts on this site we’re spoilt for choice when it comes to excellent geology in the Borders (and Scotland as a whole [in fact, the UK as a whole come to think of it]). I had a chance to visit quite a lot of these through my childhood, and loved almost every trip.
  One particular memory stands out above the rest. I think I was about 10 or 11 (because we went with my best friend from primary school, Calum). It was in September; I know that for sure because it was a National Trust walk arranged to coincide with the Scottish Festival of Geology. The walk took us along the bottom of a U-shaped valley from the base of Grey Mare’s Tail to Dob’s Linn. I remember running through the river and scrambling up scree slopes looking for Graptolites. I loved every minute of it, and have been back several times since.

• Favourite subjects at high school: At high school I was always drawn to the more science based subjects. Preferring analytical techniques and observation over hand waving discussion of social issues (I’m looking at you Human Geography) – not to put these subjects down, they’re just not “me”. By my final year I’d narrowed down to Advanced Higher Geography (focusing as much as possible on physical geography), Chemistry and Mathematics. I made a half hearted attempt to take Higher Geology, planning to teach myself and sit the SQA exams; but this fell through with no-one around capable of conducting continuous assessment or marking NABs (but my issues with the Scottish Education System can be saved for another day). In any case, my favourite subjects at this point were physical geography and chemistry. What do you get when you combine chemistry and physical geography? Earth Sciences.

• Holidays: Looking back at my childhood I was a pretty lucky kid when it came to summer holidays to interesting places. I saw the Caves of Drach (Majorca), the Lake District (UK), Pamukale (Turkey), Cheddar Gorge (UK), more glaciated uplands in Scotland and Wales than is probably healthy (UK), the volcanic landscapes of Lanzarote (Spain) and a whole lot more. While I understood little of what I was seeing at the time, and much of it is now reduced to a hazy tapestry of memories, these experiences have stuck with me. The staggering beauty of the vistas created by geological processes presented a fascinating puzzle to my young mind, I was curious to find out what created these things.

• Ithaca: The final influence I list is a member of its own group of little influences – brilliant stories about cross-discipline investigations and revolutionary discoveries (another good example is the collaborations between astronomers and geologists that take place in Planetary Geology, another interest of mine). The one that really grabbed me, however, is described in Odysseus Unbound [Wikipedia Page]. I came across a BBC news story about the subject shortly after having read the Odyssey, and my attention was seized by the combination of multiple fields working together to prove a hypothesis. It’s a brilliant story, although the science needs some more detailed examination to confirm the hypothesis, and it’s well worth a read.
  I got the chance to hear a fascinating lecture on the topic at the Geological Society of Glasgow last year from Prof. Underhill explaining the theory and detailing the evidence – a fantastic lecture which helped remind me of one of the reasons why I love science – solving puzzles. (It’s also just occurred to me that this would make a fantastic field trip for last month’s Accretionary Wedge, if only I’d thought of it at the time).

So that’s it for this brief summary of what got me interested in geosciences. I don’t know if it makes a particularly good read, but I greatly enjoyed writing it and reminiscing about what got me started on the path into this fascinating field.

We have loads of beautiful geology in our backyards here in Scotland, and there’s so much of it I still want to see. We’ll hopefully make another, longer, trip down at some point in the future. Stay tuned.

Homeward Bound

Anyway, back to our little excursion. We parked the car at the inconspicuous parking spot next to Dob’s Linn (the little valley is almost completely unsignposted or marked in any way – probably to help preserve it).

Dob's Linn from the road

We wandered up through the valley, finding the occasional graptolite rich fragment amongst the large scree slopes of black shale. Turning left we climbed up the Linn branch (a warning to people wanting to follow us, this involves clambering round some steep scree slopes – it’s not the safest excursion for the young or infirm and is extremely unwise to do alone). This branch of the gorge is really quite lovely, both geologically and aesthetically:

Some lovely, slightly folded shales to the South side of the branch

Ripple Marks (I've cheated here, this is a photo from a prior visit)

The Waterfall at the End of the Branch

That waterfall was particularly lovely last time I visited the area, in the deepest darkest Scottish Winter:

Frozen Waterfall

There are two excavated areas in Dob’s Linn: the Linn trench and the North trench. Both of these trenches show large sections of the strata, which have been examined and catalogued in detail by Lapworth and later Williams. Time didn’t allow us the opportunity to examine the North trench, however we were able to see the Linn branch trench, and examine the scree slope below it – within which many Graptolite specimens could be found.

The Linn Branch Trench

This photograph covers the border between the Ordovician (from where the photograph was taken) and the Silurian (where Hazel is sitting). Somewhere between us (I can’t put my finger on exactly where) is the FAD of Akidograptus Ascensus – the acknowledged boundary or ‘golden spike’.

After this we clambered back down and drove west to Moffat then back up the west coast. It’s worth noting that there are a great deal of excellent examples of slope failure along the road to Moffat (this area would make a fantastic day trip for a geography or geology class).

Following are a number of photographs of samples obtained from the loose scree material:

Some small fragmented graptolites - few specimens are preserved completely intact

More Examples

Not entirely sure what these are - any suggestions?

Layer of pyrite within the shale

These shales are really lovely, you can pull apart layers with your hands to reveal a new layer filled with graptolites or, as above, pyrite.

Our Transport - The Green Blur, and our mascot - Trevor the Trilobite

Once again we were incredibly pushed for time; so much so that we didn’t have time to climb up the Eildons, instead contenting ourselves with a view from afar. However, that didn’t stop us from examining some of the geology of the area. Across the road from where we parked is Bowdenmoor Quarry; a quarried mass of Sanidine-Trachyte in Silurian country rocks which shares its origin with the Eildon Hills themselves. They were all part of the same intermediate-acidic layered lacolith (with one exception, which I’ll get to shortly).

The Quarry (picture by Hazel Scott)

I collected some nice samples of Sanidine-Trachyte here:

Sanidine-trachyte - note the phenocrysts

Since we had to get moving, we headed up the road, but not before snapping some more pics.

The Mid (lacolith) and Little (vent) Hills

The largest hill (left) is a part of the lacolith, consisting of layered sheets of trachyte and felsite (I wish we’d had time to get a bit of the Riebeckite-felsite). The smaller hill on the right (which isn’t usually counted as one of the three Eildon hills) is actually a volcanic vent intruded later. It consists of a central core of basalt and quartz-porphyry as well as some agglomerate.

Before getting in the car to drive across to the west coast (via Dob’s Linn) we couldn’t pass up the opportunity for another photo.

Emma and I in front of the Wester Hill

Behind us is the reservoir (which I think is man-made) and behind that is the Wester Hill – another part of the lacolith.

The Alternative Unconformity

Since it was about 8:30pm we decided not to clamber down to it, as we were losing the light. Instead we climbed over the top to view the classic Siccar Point example of the unconformity.

Hutton's Unconformity

Again, since we were pressed for time and the cliff was in shadow we decided not to climb down and look at it close up. Instead we spent time posing for photos holding the unconformity:

Hutton's UC

Finally we walked back down the way we were supposed to have come up, stopping to look at the helpful sign explaining the whole thing.

Info Board

We then drove back up to Galashiels, and spent the night playing Guitar Hero.

Burnmouth Beach

Unfortunately we arrived shortly before high tide, with most of the fossiliferous beds marked in our helpful guidebook (McAdam et al. 1992) drowned by the sea. Despite that, the cliffs to the South looked interesting so we ambled down there, stopping occasionally to look at the lovely micaceous sandstone pebbles covering the beach. Some of the features seen on the cliffs are shown below:

Steeply Dipping Micaceous Sandstone

Small Deformation Bands

Odd weathering effect (heterogeneous cementation?)

One of the interesting things found here (which none of us had encountered in the field before) was what appears to be a geode:

Geode

Cross Bedding was also evident in some of the rock; although it also varied from finely laminated to massive in sections.

Cross-Bedding

At this point we ran out of beach, so were forced to climb up on top of the cliffs to continue southwards.

Steeply Dipping Beds submerged by tides

We continued south, seeing some wonderful looking things from afar. However, due to a combination of high tides and being on top of a cliff we weren’t able to inspect them up close.

More reddish Sandstones

A Sea Stack colonised by Seagulls

This sea stack is apparently called the Maiden’s Stone and, from a distance, appears to be a cross-bedded sandstone.

We stopped for a quick snack above a ruined old cottage; which the map claims is an old fishery.

The view down from our picnic spot

It was around 18:00 now (we’d had a late start) so we decided to head back to the car, so that we would have time to visit our next two stops: The excellent Chippy in Eyemouth and Siccar Point.

Hazel and Emma

Recommended Reading:

McAdam, A. D., Clarkson, E. N. K., and Stone, P.. (1992). Scottish Borders Geology: an excursion guide. Scottish Academic Press.

My Apps (Click to view full size)

All of the applications shown are freely available (although some are ‘trial’ or ‘lite’ versions of paid apps).

Disclaimer: If you break your iPhone in the field, drop it in a rockpool etc. it is totally not my fault ;)

Update: A quick google around indicates that I’m not the first to think of this. Does anyone else have any useful app suggestions?

Another Update (3/9/09): There’s been quite a bit of discussion of this elsewhere – here’s some links.

This time we checked the opening times, made sure that there were no public holidays on (not even Glasgow City Council could use Oak Apple Day as an excuse surely) and even packed lunch supplies (ie we stopped at a newsagents to buy salt-laden Dairylea concoctions).

Arriving at Victoria Park we were greeted with this sight:

It's Open!

Not only was it open, it was actually staffed! (albeit by a guy sitting in a van eating his lunch).

We headed inside to have a good nosey around.

The view inside.

8 or 9 stumps can be seen from the viewing platform, many with their roots visible and intact. The casts of the trees are so good in places that you can clearly see the impressions of the ‘bark’ preserved. Also preserved are sections of trunk and branches scattered around on the floor.

Trunk Section

Illuminated Stump

Note the preserved surface details

The walls of the building itself have displays explaining the formation of the deposits, as well as describing the location at the time of fossilisation. Examples of various plant and animal life are shown, including some samples donated from the Hunterian Museum.

How these fossils formed

Interestingly, when discovered these deposits also included organic material left on the trees from fossilised plant material. This has since been removed or weathered off (I wonder if anyone got a sample of this; it might be worth looking at from a biomarker perspective).

Bark Impressions

Finally, after a good nose around, we went and played in the sun for a while:

"Race you to the top!"

And that’s all folks! For the previous posts in this series look here.

Once again I highly recommend the Geological Society of Glasgow’s guidebook: Geological Excursions around Glasgow & Girvan (ISBN: 0-902892-09-6),