Storm beaches have I loved
The answer to yesterday’s geo-puzzle is revealed to be a storm deposit of boulders, 20 m above sea level!
scotland
Weathering along perpendicular joint sets, Arran
Check this out: That’s a beautiful example of weathering in a dolerite dike on Arran. The igneous rock was broken along two more or less perpendicular joint sets, and then fluid flow along those fractures helped “rot” the adjacent rock through oxidation and hydrolysis. The resulting brownish weathering rind grows at the expense of the … Read more
Stac Fada
The evidence for a meteorite impact origin for the Stoer Group’s Stac Fada member seems to stack up. Engage in a virtual field investigation on Mountain Beltway.
Lugworm casts on the beach, Islay
Who dwells beneath the sands of Islay? Lugworms do. These embedded annelids process the sediment for food, extruding the undigested sand in charismatic piles that adorn the beach of Loch Gruinart.
Friday fold: Kink folded Dalradian metasediments
Let’s reminisce back to the Walls Boundary Fault on the Ollaberry Peninsula of Shetland today. Here’s a 3D model to go along with the ones I posted last time: It’s a little ragged, but so am I at the end of the workweek! Happy Friday. Have fun spinning this thing.
A virtual field trip to the Grind of the Navir
On the northwestern coast of the Northmavine Peninsula of Shetland, there is an unusual coastal landform: a gate-like entrance to an elevated amphitheater, like something out of Tolkien, and a storm beach of slab-like boulders inland of that.
An oddball at Eshaness
In eastern Shetland, the sea chews away at the innards of a Devonian stratovolcano. But there’s an odd visitor there too – and we’re not talking about the blogger.
Dore Holm
The scenic arch of Dore Holm (“Door Island”) in Shetland shows off the most efficient way of breaking a slab of rock. The island’s shape is a reflection of the parsimonious nature of natural deformation.
Shear zones in Scottish gabbros
A quest to visit the “first shear zones” described in the scientific literature leads to an alternate location, and some GIGAmacro images of samples from the real, original spot.
Friday fold: Smaull Graywacke at Saligo Bay, Islay
On the western coast of Islay, Saligo Bay showcases turbidites of the Neoproterozoic Colonsay Group. The Smaull Graywacke shows Caledonian (late Ordovician) folding and cleavage superimposed on world-class graded bedding. There’s also a nice dolerite dike to examine.