Looking at Ordovician carbonates in Germany Valley, West Virginia, a few weeks ago on Rick Diecchio’s GMU sedimentology and stratigraphy course field trip: Lots and lots of brachiopods… Crinoid columnals mized with brachiopods: A set of coarsely-infilled trace fossils: Crinoid stem: Nice strophomenid brachiopod: Bryozoan? Receptaculid?
Recently, I posted about an excellent road cut in Fort Valley showing well-developed 10 cm+ Zoophycos trace fossils. Presented here are three new GigaPan images (two outcrop; one macro) of Zoophycos from the Devonian-aged Mahantango Formation: link link link These images are part of a new “virtual field trip” that I organized to supplement my … Read more
A report from the field: new outcrops of Ordovician-aged turbidites featuring geopetal indicators, fossil content, and a structural overprint imparted during Pangaea’s assembly.
A morning’s field trip yields an outcrop of excellent Zoophycos trace fossils in southern Fort Valley, Virginia.
At the Spiral Tunnels overlook on the Trans-Canada Highway, you can look at trains. Or, you can check out some lovely trace fossils in boulders which divide the viewing area from the highway: These are in the Gog Formation, a Cambrian-aged quartz arenite, mostly fused to quartzite nowadays… I know which subject I would choose … Read more
Some boulders seen on the trail to Helen Lake sported lovely sets of Skolithos trace fossils. Here are two boulders, with the perspective on the tubular paleo-vertical Skolithos burrows being “map view”: Another boulder, in the middle of the trail, showed them in a fine cross-sectional view: (click to enlarge substantially) It also included some … Read more
Look at this! A whole boulder made of trace fossils. Three photos, each more progressively zoomed in than the last. Update: The @ichnologist identifies these as perhaps Thalassinoides.
For those inclined toward trace fossils… …This is from Banff National Park, Alberta, Canada. I saw it on the trail to Consolation Lakes from Moraine Lake. I do not recall rock type – could be dolostone, could be Gog quartzite. It’s float (loose; not in situ), but I infer the photographed surface is the underside … Read more
Good morning. Here are two images from last March’s “Border to Beltway” field trip to West Texas, on the north flanks of the Cristo Rey laccolith. Specifically, these are Cretaceous strata of the Anapra Sandstone, looking at the bedding plane of the rocks. Cutting across bedding are a series of fractures (joints) that have been … Read more
Good morning! Let’s take a walk up the east side of the Franklin Mountains, north of El Paso, Texas, to walk across the Great Unconformity. The basement rock exposed here is the Red Bluff Granite, a 1.1 Ga felsic magma that intruded the columnar basalts of the Mundy “Breccia” and the Castner Marble. (It is … Read more
On a cold winter’s day, Callan harks back to a summer’s afternoon fossilizing in the Rocky Mountains. A few choice images of Mississippian-aged marine invertebrates are shared.
On my morning walk earlier in the month, I encountered this trackway: Those are percheron (big breed of horse) hoof-prints, and the tracks of an authentic one-horse open sleigh, like the one invoked in “Jingle Bells!” Our neighbor, Don Warlick of Secret Passage Ranch, brings the sleigh out for neighborhood fun when conditions are right… … Read more
In areas of soil protected from the rain, we find antlion pits in our yard… These are traps, dug and maintained and occupied by the larvae of the family Myrmeleontidae. When a passing insect stumbles in, the antlion will throw sand grains and cause the hapless bug to tumble down, where the antlion snags it … Read more
Archaeology meets geology in this visit to the Piney Branch valley of Rock Creek Park in Washington, D.C. Cretaceous deposits of cobbles of Cambrian quartzite were quarried by Native Americans and modified into tools thanks to the fact that they break with a conchoidal fracture.
Last week, I mentioned some geologizing with the family in the Staunton area. The furthest west we ventured was to the road connecting Deerfield, Virginia, with West Augusta. There, the Brallier Formation is well exposed in a dramatic roadcut. Explore it for yourself in this M.A.G.I.C. GigaPan: link The Brallier is turbidites, shed off the … Read more
Are you into structure? Sedimentology? Stratigraphy? Well, I’ve got some good news for you – I’ve imaged several key outcrops on the newly-discovered (to me) roadcut on South Page Valley Road, showcasing the middle Martinsburg Formation turbidites (and their Alleghanian structural overprint). link link link link link link See if you can find: an anticline … Read more
Yesterday, I worked on my sabbatical project, the Mid-Atlantic Geo-Image Collection (M.A.G.I.C.). Whether I go outside on a given day to shoot GigaPans of local geology depends on multiple factors: (a) How’s the weather? (b) Do I have to watch Baxter? (c) Can I bring Baxter with me? (d) How are the lighting conditions? Yesterday … Read more
Everything’s bigger in Texas, even the footprints…
All seen last March in Death Valley, at Mesquite Dunes…. within ten minutes of one another.
Here’s a terrific outcrop to start off the new year at Mountain Beltway. We’re back in the Bighorns of Wyoming here, on highway 16, traversing the southern portion of the range en route from Buffalo to South Pass City. Click to enlarge Annotated, expanded, and Easter-egg-embedded: Click to enlarge From a different perspective (uphill a … Read more