Friday fold: Kinked Lynchburg metasediments near a soapstone body
Happy Friday! Here are some kink-folded metasediments from Virginia’s Lynchburg Group to help usher in the weekend.
Happy Friday! Here are some kink-folded metasediments from Virginia’s Lynchburg Group to help usher in the weekend.
Inside the Blue Ridge (in an 1850s-era railroad tunnel), Callan finds folds and boudinage that formed during Appalachian mountain-building.
Because I’m putting together a field course for spring break 2020 to Death Valley California, I was looking through old Death Valley photos this week, from the last time I went to that special place. It was seven years ago! How time flies… This one is in Mosaic Canyon, and was taken by my student … Read more
A moderate mesoscale monocline at Watern Cove, Newfoundland, shows off multicellular animal fossils of the Ediacaran Mistaken Point Formation.
The 2017 Virginia Geological Field Conference had a heavy arkose infusion. Meet some of these feldspar-rich Neoproterozoic sediments of the Lynchburg Group.
My son and I hiked Compton Peak in Shenandoah National Park this morning, and saw these two lovely examples of xenoliths. The example above is small, but it shows clearly the difference between the coarse, felsic basement rock (Mesoproterozoic granitoid, comprising the xenolith) and the surrounding fine-grained dark green metabasalt of the Catoctin Formation (Neoproterozoic). … Read more
Remember the diamictite I featured here a few weeks ago, from Islay? It was the one that might be a Snowball Earth diamictite. Well, if you follow Snowball Earth science at all, you’ll doubtless be aware that the glaciogenic sediments are characteristically overlain by “cap” carbonates. There’s a stratigraphic successor to the Port Askaig Tillite, … Read more
It’s Friday! Today’s fold comes to you from Neoproterozoic metasediments on the west side of Islay, at Machir Bay.
One fun thing about examining the Port Askaig Tillite in the field is to find odd-shaped exemplars of the unit lying on Islay’s beaches. My favorites were shaped like wands, or antennae, or perhaps the drumsticks freshly detached from a Thanksgiving turkey… a big clast at one end and then a thin septum of the … Read more
The Port Askaig Tillite is a Neoproterozoic diamictite on the eastern shore of Islay (Scotland) that may record a “Snowball Earth” glaciation.