Callan attends the Geological Society of Washington’s fall field trip, examining the relationship between grape-growing and the underlying geology of two provinces in northern Virginia: the Blue Ridge and the Valley & Ridge. With GSW compatriots, Callan visits Hume Vineyards in the Blue Ridge basement complex and North Mountain Winery in the Shenandoah Valley. This is part I.
Another Friday, another fold. …By another Bentley!
The Friday fold is a structural dome in Wyoming, as seen out an airplane window.
Callan hosts the 357th installment of the popular satellite imagery / geologic search game “Where on (Google) Earth?”
The Friday fold is a selection of five fold photos from the Selkirk Fan in the Omineca Belt of British Columbia, submitted by structural geologist Marek Chichanski of De Anza College (California).
Grab your coffee and join Callan & Lily for a stroll along the quartzite cliffs of Hermanus, South Africa. Bedding, cross-bedding, joints, faults, veins, folded veins, and faulted veins all await you there in the morning light.
The Friday fold, delayed by a week from last week’s contest, appears in Yoho National Park, British Columbia, near the “Natural Bridge” over the Kicking Horse River.
A weekend expedition to GigaPan the C&O Canal’s singular Paw Paw Tunnel results in an exposition on Devonian sedimentation, Alleghanian mountain-building, structural geology, and the incision of the Potomac River to produce entrenched meanders.
A few photos from the Canadian Rockies illustrated the characteristic “look” of glacial striations. Callan also demonstrates how they can be used for outright tomfoolery.
Royal Tyrrell Museum geologist Dave Eberth donates time and expertise to help Callan’s students understand the Cretaceous-aged Horseshoe Canyon Formation in central Alberta.
The Friday fold is a seaside outcrop of soft sediment deformation (not post-lithification tectonic deformation) on Kodiak Island, Alaska.
The Friday fold is a kink fold in thinly-laminated limestone from the same site as yesterday’s mysterious orange oncoids.
Callan presents a mystery rock found in blocks of sedimentary rock on a talus slope near the Consolation Lakes in Banff National Park, Alberta. Are they orange oncolites? Or alien embryos? 🙂
Ever seen an armored mud ball? In this post, Callan encounters a small herd of these geological oddities in a coulee in southern Alberta.
The Friday fold is presented in photo, annotated photo, and GigaPan formats. It’s a cleaved anticline in lower Martinsburg Formation limy slate from Page County, Virginia. See if you can spot Mr. E. coli in the GigaPan!
Callan’s Canadian Rockies field course visits an outcrop of Cambrian slate in Yoho National Park, British Columbia. Folded and boudinaged carbonatite dikes are seen.
Callan and his students narrowly miss being stranded in Banff National Park when a rainstorm triggers a mudslide that closes the TransCanada highway.
A showcase of geologic structures observed between downpours of rain at Floe Lake, Kootenay National Park, British Columbia. Cleavage, bedding, folds, faults, and strain are all presented for the discerning structural reader’s edification and titillation.
Have you ever seen a black rhyolite? Neither had geoblogger Callan Bentley – until he went to the Franklin Mountains of West Texas.
Callan shares some photos of “leopard rock” (porphyritic mafic dikes) seen along the Beartooth Highway, northeast of Yellowstone National Park.