Gog Formation quartzite, Yoho National Park, British Columbia, CanadaMay 11, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 44400 x 20648 pixelsCambrian quartzite showing primary sedimentary structures.
Bedding is oriented 111°/15° (right-hand rule). | Conococheague Formation at Mulberry Run, showing stromatolitesMay 12, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 109912 x 38528 pixelsCambrian limestone, from just west (left) of this outcrop: https://viewer.gigamacro.com/view/d3DsbJAOwe0NbHl2 | Helen Lake Stromatolites 3May 11, 2020 by magic-gigapansImage: Aaron Barth, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 36664 x 14732 pixelsCambrian-aged stromatolites outcropping above Helen Lake, Banff National Park, Alberta, Canada | AmphiboliteMay 5, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 30664 x 14092 pixelsAmphibolite similar to the amphibolite exposed on the Billy Goat Trail.
Amphibolite is a metamorphic rock very rich in the mineral hornblende (an amphibole), which shows up black in this image. The white mineral in the rock is plagioclase feldspar.
This is a very mafic metamorphic rock, with large crystals. Amphibolite occurs as large, folded, tabular masses in the area of the Billy Goat Trail.
This cut and polished surface of an amphibolite (very similar in texture and composition to amphibolite seen on the Billy Goat Trail) is intended to correspond with this surface (natural and weathered) of the same specimen:
https://viewer.gigamacro.com/view/GxwANj9Z8pSFBR0h
To explore an outcrop of amphibolite on the Billy Goat Trail, click here: https://viewer.gigamacro.com/view/ZbrknhGx8B6TESUT | Weverton FormationMay 5, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 37180 x 15328 pixelsCambrian quartz sandstone from the Blue Ridge; showing primary sedimentary features. | Flat pebble conglomerate, Gros Ventre FormationApr 29, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 56488 x 24700 pixelsCambrian-aged flat pebble congolomerate from the Gros Ventre Formation, collected in the Bighorn Range of Wyoming.
To explore more gigapans of this sample, follow these links:
https://viewer.gigamacro.com/view/dGmOemyAt8L6grsK
https://viewer.gigamacro.com/view/3tE8Bwv4U4naCVDy
Source outcrop:
https://viewer.gigamacro.com/view/vUny6029hDc0Xz1p | Quartzite of the Weverton Formation, Thoroughfare Gap, VirginiaMar 24, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 40144 x 21000 pixelsCambrian-aged recrystallized (due to Appalachian mountain building) quartz arenite of the Chilhowee Group (Sauk Transgression), Bull Run Mountains Natural Area Preserve, west of Haymarket, VA. | Brecciated Antietam FormationApr 10, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 23864 x 25708 pixelsCemented with iron and manganese oxides. Western Blue Ridge, Virginia. | Salterella Grit, North-West Highlands, ScotlandApr 17, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 27928 x 20164 pixelsPart of the Cambrian succession exposed north of Loch Assynt. Note the Skolithos trace fossils. Less obvious are small, cone-like Salterella. | Chancellor Formation slate, near Yoho National Park, British Columbia, CanadaMay 6, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 30744 x 36296 pixelsCambrian-aged deep basin mudrock, cleaved to slate during Canadian Rockies mountain building (Laramide Orogeny, late Mesozoic to early Cenozoic). | Sugarloaf Mountain quartziteApr 10, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 21308 x 19344 pixelsPrimary sedimentary grains in evidence, in addition to a bit of milky hydrothermal quartz (lower edge) from a vein. | Weverton Formation exposed at Thoroughfare Gap, VirginiaMay 1, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 70164 x 66524 pixelsThis is the eastern limb of the Blue Ridge Anticlinorium, where Cambrian-aged quartzites of the Weverton Formation dip moderately east. Bedding (visible as dark bands of heavy minerals) is cut across by steeply-dipping quartz veins and at least two joint sets, stained by iron oxides. | Storm deposit in glauconitic sandstoneMay 5, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 45752 x 22516 pixelsStorm deposit in the Upper Cambrian-aged glauconitic sandstone of the Reno Member of the Franconia Formation in southeastern Minnesota. | Rock wall at Knockan Crag, North-West Highlands, ScotlandApr 17, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 53644 x 24120 pixelsAn artistic interpretation of the local geology and the shuffling of layers that trumps superposition. | ChalcopyriteApr 10, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 32206 x 28109 pixelsChalcopyrite in Conococheague Formation limestone. | Crossbedding preserved in phylliteApr 7, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 62560 x 32272 pixelsCrossbeds, a primary sedimentary structure, preserved in Station Hills phyllite from the upper Cambrian-lower Ordovician. Collected in the Piedmont Province in northern Virginia. | Chancellor Group slate, Yoho National Park, British Columbia, CanadaMay 7, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 27336 x 29992 pixelsMudrocks with fine laminations from basinward of the Cathedral Escarpment, cleaved and folded during Canadian Rockies mountain-building.
The orientation of bedding varies, but here's a representative measurement: 095°/30° (right-hand rule). Cleavage is more consistent, at 109°/76°. | Quartz-cemented breccia, Antietam Formation quartzite, western Blue Ridge, VirginiaMay 6, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 16888 x 21552 pixelsThe Antietam Formation (Cambrian, Sauk sequence) is brecciated in many (but not all) places along its outcrop belt in the western Blue Ridge. The nature of these breccias is enigmatic, though the traditional story is that they are "fault breccias" related to the thrusting of Blue Ridge rocks over younger strata of the Valley & Ridge. The breccias are sometimes cemented with quartz, sometimes with iron oxides, sometimes with manganese oxides. | Fucoid Beds, North-West Highlands, ScotlandApr 20, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 39488 x 26796 pixelsSiltstones and shales, part of the Cambrian transgressive sequence that lies between the Torridonian and the Moine. | Lamprophyre dikes at Mather Gorge, Great Falls, VirginiaMay 7, 2020 by magic-gigapansImage: Sam Adler, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 50032 x 12596 pixelsIn this panorama, the Potomac River can be seen flowing through Mather Gorge in Great Falls Park. It was taken from the Maryland side of Great Falls, looking towards the Virginia side. Cliffs of metagraywacke line Mather Gorge, and have been dated at ~460 Ma. Steeply dipping lamprophyre dikes can be seen intruding into the metagraywacke. A crystallization age of ~360 Ma has been obtained from K/Ar dating of biotite in the dikes. | Devil's Racecourse, Ft. Ritchie, MarylandMay 13, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 106476 x 15992 pixelsDevil's Racecourse in Ft. Ritchie, MD is a 700-meter-long blockfield created when the area experienced a periglacial climate during the Pleistocene. It is thought that boulders of Weverton quartzite from South Mountain on the west and Catoctin metabasalt from the east weathered out of their respective mountains and were gradually transported and deposited here by gelifluction. In non-dry periods, visitors to Devil's Racecourse can hear a stream running beneath the blockfield, and can even see it if they peer down the right holes.
View is to the west. | Outcrop of upturned Paleozoic strata on Highway 16Apr 29, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 99808 x 34968 pixelsCrossing the southern Bighorn Range in Wyoming on Highway 16, there is a nice outcrop that illustrates (in part) the geologic history of Wyoming. Perspective of the gigapan is looking from south to north. The outcrop is on the eastern side of the Bighorn Laramide Uplift. From left (west) to right (east), we see the Gros Ventre Formation green shales and sandstones, the Gallatin Limestone, the Harding Sandstone (white), the Bighorn Dolostone ("Bighorn Dolomite"), a valley etched into the Darby Formation, and the Madison Limestone. The Gros Ventre and Gallatin are Cambrian. The Harding and Bighorn are Ordovician. The Darby is Devonian. The Madison is Mississippian. All of them are tilted (younging to the east) due to the overall antiformal structure of the Bighorn Range: it's a Laramide uplift bounded by the Powder River Basin on the east and the Bighorn Basin (both Laramide basins) on the west.
Search the image for the charmismatic green flat-pebble conglomerate of the Gros Ventre Formation and Gallatin Formation, trace fossils, and a bucket of industrial-grade lubricant that someone dumped on the roadway.
Hand samples of the flat pebble conglomerate can be explored here:
https://viewer.gigamacro.com/view/dGmOemyAt8L6grsK
https://viewer.gigamacro.com/view/3tE8Bwv4U4naCVDy | Bedding / cleavage relationships in Chancellor Group slates, Yoho National Park, British Columbia, CanadaMay 11, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 32028 x 25816 pixelsNice structure! these are Cambrian-aged mud and sand deposits of the Chancellor Group, folded and cleaved during the compression that accompanied Canadian Rockies mountain-building.
Bedding is oriented 095°/42° (right-hand rule).
Cleavage is oriented 104°/70° (right-hand rule). | Double unconformity at Beinn Garbh, North-West Highlands, ScotlandApr 17, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 59500 x 8608 pixelsTwo unconformities for the price of one: Beinn Garbh (north of Canisp), viewed from the north across Loch Assynt. Most of the mountain is Torridonian Applecross Formation, with Lewisian gneiss below (making up the hummocky ground between the mountain and the loch) and with gray Cambrian quartzite on the left (east) dipping off to the left (east) at about 15 degrees. | The nascent NOVA Annandale rock garden, as of May 2012May 13, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 80464 x 30292 pixelsThis is a small section of the rock garden south of the CS building on the Annandale campus of Northern Virginia Community College.
Representatives from several Virginia geologic provinces can be seen here.
This GigaPan was made as part of the Mid-Atlantic Geo-Image Collection (M.A.G.I.C.). | Flat pebble conglomerate, Gros Ventre FormationApr 29, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 59740 x 28300 pixelsCambrian-aged flat pebble congolomerate from the Gros Ventre Formation, collected in the Bighorn Range of Wyoming.
To explore another gigapan of this sample, click either of the links below:
https://viewer.gigamacro.com/view/wFxi9darXQbLp5dw
https://viewer.gigamacro.com/view/3tE8Bwv4U4naCVDy
To explore a gigapan of the source outcrop, click here:
https://viewer.gigamacro.com/view/vUny6029hDc0Xz1p | Helen Lake stromatolites and Cirque Peak, Banff National Park, Alberta, Canada.May 11, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 40100 x 21484 pixelsWhat a story to be seen here: Cambrian sedimentation (stromatolites in foreground, plus continental redbeds up on the peak), deformation during the orogeny that built the Canadian Rockies, and finally glaciation and deglaciation.
Bedding in the stromatolite rich layer is oriented 295°/14° (right-hand rule). | "Rocks of Virginia" garden at the DGMRMay 14, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 107880 x 32668 pixelsThe Commonwealth of Virginia's Department of Geology and Mineral Resources has their offices in Charlottesville, Virginia. Outside their building is an exceptional collection of large rock samples from across the state. Samples include igneous, sedimentary, and metamorphic rocks from all five physiographic provinces, and spanning more than a billion years of geologic time. This gigapan was shot on April 14, 2011, during the lunch break of the DGMR's annual "Geology of Virginia" symposium. A full guide to the rocks in the garden is published online by the DGMR at:
http://www.dmme.virginia.gov/DMR3/dmrpdfs/vamin/VM 48_2_3.pdf
The map of the garden in that document shows that this gigapan was shot from the sidewalk between the two samples of #31, the Leesburg Conglomerate and #35, the Antietam Formation quartzite, with its characteristic linear Skolithos trace fossils.
A blog post describing some of the rocks is online at:
http://www.nvcc.edu/home/cbentley/geoblog/2008/12/rock-garden.html | Trilobite Elrathia kingiMay 1, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 7452 x 8152 pixels | Grudaidh Formation w/ vogesite sill, faultedApr 20, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 29944 x 25668 pixelsGrudaidh Formation w/ vogesite sill, faulted |
