Funzie
Funzie Bay in eastern Fetlar, Shetland, is the place with a stretched-pebble metaconglomerate that triggered the development of the Flinn Diagram. Join Callan on a pilgrimage of structural geology to this special place.
structure
Friday fold: orogeny in a cobble
Happy Friday. Thank goodness it’s the last one before this horrible election season finally concludes. Let’s celebrate with two cobbles from the beach at Papil Water, Fetlar, Shetland. They show small-scale folds in metasedimentary and metavolcanic rocks of Ordovician or Silurian age, part of the ophiolite complex that makes up most of Fetlar. Each is … Read more
Friday fold: a miniature ramp and flat
Sometimes you find big ideas in small places. Here, a South African chert boulder mimics in miniature fold and thrust belts the world over.
Friday folds: Dalradian schists at St. Ninian’s Isle
Remember St. Ninian’s Isle? It is connected to Mainland Shetland by a tombolo. But it has rocks there, too. Here are some outcrops on the beach: If you visit these schisty fins, you’ll find they are populated by a cavalcade of small folds. Some of the folds are crisp things known as kink bands: Annotated … Read more
Tension gashes in Malmesbury metasediments near Sea Point Contact
A small structural geology treat – several en echelon arrays of tension gashes (quartz-filled veins) in Malmesbury Group metasediments, Sea Point, South Africa.
Friday fold: roadside in Ladismith/Kleinkaroo
Martin Schmidt again contributes a fold – this time from his summer trip to South Africa: Pretty great! This is part of the Cape Fold Belt. Perhaps some of you will drive by it when you go to the International Geological Congress in South Africa later this month! You can view the site in the … Read more
Friday fold: Lewisian gneiss near Tarbet, North-West Highlands, Scotland
A quick Friday fold here from the North-West Highlands of Scotland: These are Lewisian gneisses exposed on a headland northwest of the little outpost of Tarbet (where the Handa Island ferry departs from). I was out there in search of shear zones, but I found plenty of nice folds, too. There are two main folds … Read more
Friday fold: The walls of Scalloway Castle
When in Shetland, one of my first stops was the museum in Scalloway, and one of the ancillary benefits of visiting there is the castle next door: Scalloway Castle includes building stones derived from the local limestone – a Neoproterozoic unit that has recently been chemostratigraphically correlated with Snowball Earth cap carbonates elsewhere in the … Read more
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 … Read more
Two virtual weathered-out dikes in a fjord in eastern Iceland
Two 3D models for you today, both produced by my student Marissa Dudek, using photo sets I gathered in Iceland: Photoscan model by Marissa Dudek (That one has paleomag holes drilled into it!) Photoscan model by Marissa Dudek (That one I’m particularly pleased with. Given the circumstances of image acquisition, this is a very good … Read more