You are browsing the archive for June 2016 - Mountain Beltway.
30 June 2016
Virtual field trip to Siccar Point, Scotland
Time for another virtual field trip on the Geologist’s Grand Tour of the United Kingdom: the most famous outcrop in the world. Today, we visit Siccar Point, Scotland. You’ve probably already seen photos of this place – they usually look something like this: To those who aren’t familiar, here’s what going on: There are two sets of strata here – and the contact between them is an ancient erosional surface. …
29 June 2016
Trace fossils in sandstone from Barns Ness
Check out this sandstone cobble I saw at Barns Ness – it comes bearing gorgeous trace fossils. Can you spot them? Lens cap for scale in all these photos. The next three are close ups of the burrows from the previous image: Plus two more, from other cobbles I encountered::
28 June 2016
“Dunbar marble” at Barns Ness, Scotland
Thanks to the website ScottishGeology.com, run by Angus Miller, I learned of Barns Ness, a Mississippian-aged limestone fossil site on the shore not far from where we are staying at Dunbar. We ventured out there on Saturday afternoon, in search of fossils. The presence of the Dunbar Cemenet Works nearby is an indication that this is the most extensive limestone outcrop in central Scotland. I set my field assistant loose …
27 June 2016
Small faults in upper Old Red Sandstone, Dunbar, Scotland
Dunbar, Scotland, is a nice little seaside town that also happens to be the birthplace of the conservationist John Muir. My family and I have been based out of here this week on our European geological GigaPan expedition. But on our first morning, upon visiting Siccar Point (which is nearby), I threw out my back, and spent most of the next two days recuperating. I did manage a short walk …
25 June 2016
A virtual field trip to the Giant’s Causeway, Northern Ireland
Some of planet Earth’s best examples of basaltic cooling columns are found at the Giant’s Causeway in Northern Ireland. In this post, explore four different kinds of interactive digital media as a way of experiencing the Causeway virtually, from the comfort of your computer.
24 June 2016
Friday fold: Dalradian schist at Cushendun, Northern Ireland
Same beach as the Cushedun conglomerate post earlier in the week – but here we see the schist into which the rhyolite dikes intruded: It’s been folded! Happy Friday. Hope your weekend is rejuvenative and fun.
23 June 2016
Mega-trace fossils in the floor of the Old Bushmills Distillery, Northern Ireland
We arrived at Old Bushmills at 4:06pm, and the last tour of the distillery for the day had left at 4:00. But all was not lost – We were delighted to see that the visitor center area was paved in slabs of shale with tremendously large, well-preserved trace fossils – sinuous burrows parallel to the bedding plane, in some cases cross-cutting or looping back over themselves! Great stuff – balm …
22 June 2016
Shattered chert breccia cobbles, Church Bay, Rathlin Island
My GigaPan expedition has landed at Rathlin Island, north of Northern Ireland, within view of Scotland, for a few days. The beach on Church Bay is cobble-covered and steep, and the cobbles reflect the island’s geology, with some anthropogenic components thrown in for flavor: Link GigaPan by Callan Bentley But I was struck by these two cobbles, each showing a pervasively shattered breccia of chert: To me, that is not …
21 June 2016
Porphyritic rhyolite dike seen on the beach at Cushendun
At the opposite end of the beach at Cushendun, Northern Ireland, we found some outcrops of schist – I’ll be featuring some of them as Friday folds later this week. But cutting across the schist was a pink porphyry, with big well-formed potassium feldspars. I splashed some water from the Irish Sea onto it to increase the contrast: Here’s a handheld GigaPan image, so you can explore it for yourself. …
20 June 2016
Cushendun Conglomerate of the Cross Slieve Group, Northern Ireland
Want a geological irony? Here’s one! You’re looking at a rounded boulder of Cushendun Conglomerate, a Devonian “Old Red Sandstone” unit (Cross Slieve Group) exposed at Cushendun Caves, Northern Ireland, U.K. The irony lies in the repetition of history – a tumbling environment of high water energy, rounding cobbles and boulders and depositing them, in order to make the conglomerate. And now, ~400 million years later, history repeats itself, with …