west virginia

Currents in the Devonian deep

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This blog has been noticeably photo deficient lately! Time to remedy that. Today, I offer you a couple of shots of the Brallier Formation (shale / fine-grained sandstone) in West Virginia’s Valley & Ridge province, a few miles northwest of Moorefield, on the newly-opened section of New Route 55. The Brallier was deposited in a … Read more

Friday fold: Anticline / syncline pair

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Today’s fold is an anticline and its neighboring syncline, both exposed along a newly-opened stretch of New Route 55, west of Moorefield, West Virginia. The new Route 55 is a classic porkbarrel boondoggle courtesy of the late Senator Robert Byrd, but doggone if it didn’t open up some lovely new roadcuts. Here’s a stitched image … Read more

Friday fold: the Devil’s Backbone

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The Friday fold is a guest photo by James Edward Bailey, a 5th grade student from Reston, Virginia. It is the anticline shown is known as “the Devil’s Backbone,” located near Marlinton, West Virginia, right on the boundary between the Valley & Ridge province and the Appalachian Plateaus. It clearly shows differential weathering of weaker layers and tougher layers. …Also some lovely fall colors!

Conglomerate from Dolly Sods

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While my focus was more on bugs and plants than geology this time around, I did hike a new trail at Dolly Sods this past weekend, and on that trail I found several nice boulders of conglomerate. These stood out as being much coarser than the pervasive quartz sandstone of the Pennsylvanian-aged Conemaugh Group which … Read more

Let’s coin a name for this phenomenon

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I didn’t mention it yesterday, but there was one other structure that I saw at my newest outcrop on New 55. This is it: That’s a bunch of fractures. The broken rock is being altered by preferential fluid flow through the fractures. The fluid is not inert; it’s chemically active, and reacting with the rock. … Read more

Dolly Sods

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Over the long Labor Day weekend, my fiancée Lily and my friend Seth and I took a three-day backpacking trip in the Dolly Sods Wilderness area of West Virginia: Dolly Sods is a unique place, a little patch of flora that is more typical of Canada. It sits atop the eastern Continental Divide, and most … Read more

Harpers Foldry

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Cleaning out the backlog of photos I haven’t popped up here yet… Here’s three shots from last weekend, of folds (some kinky) which deform Harpers Formation foliation, just south of Harpers Ferry, West Virginia: The Harpers is a Cambrian-aged lagoonal mudrock, dated via Olenellus trilobites in Pennsylvania. It is part of a transgressive sequence that … Read more

Overturned bedding at Maryland Heights

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The Lilster & I drove out to Harpers Ferry, West Virginia, today, and crossed the Potomac River to hike up to the overlook at “Maryland Heights,” which is what they call the Blue Ridge north of the river. On the way uphill, I noticed this nice example of Harpers Formation bedding and cleavage dipping in … Read more

Flames and pillows, Route 55

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I took a look at some interesting blobby structures in the Swift Run Formation last week, and walked readers through my logic in tentatively concluding that they were ball & pillow structures (soft sediment deformation), though overprinted by a pervasive (Alleghanian) cleavage. As we move west in the Appalachian mountain belt, the rocks are less … Read more

Transect debrief 6: folding and faulting

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Okay; we are nearing the end of our Transect saga. During the late Paleozoic, mountain building began anew, and deformed all the rocks we’ve mentioned so far. This final phase of Appalachian mountain-building is the Alleghanian Orogeny. It was caused by the collision of ancestral North America with the leading edge of Gondwana. At the … Read more

Transect debrief 5: sedimentation continues

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We just looked at the Chilhowee Group, a package of sediments that records the transition for the North American mid-Atlantic from Iapetan rifting through to passive margin sedimentation associated with the Sauk Sea transgression. Well, if we journey a bit further west, we see the sedimentary stack isn’t done telling its story. The saga continues … Read more

Transect debrief 4: transgression, passive margin

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…So where were we? Ahh, yes: an orogeny, and then some rifting. What happened next to Virginia and West Virginia? Let’s consult the column… After the rifting event opened up the Iapetus Ocean, seafloor spreading took place and tacked fresh oceanic crust onto the margin of the ancestral North American continent. As North America (“Laurentia”) … Read more

Transect Trip 27: fluvial overbank deposits

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Over on the far right by Chuck Bailey (yellow shirt) you can see the crescent-shaped profile of a river channel (gray color). To the left of that, you can see levee deposits, and beyond that (to the left) crevasse splay deposits and the floodplain (dark red mudstones). This is in the Hampshire Formation, part of … Read more