Brachiopods and crinoid stems in Mississippian-aged Reynolds LimestoneMar 31, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 35944 x 25620 pixelsClick here to explore the obverse of this sample:
https://viewer.gigamacro.com/view/cdHx2PQfUM7Zt7mG | Geopetal fossils in LimestoneSep 1, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 32255 x 25728 pixels | Reynolds Limestone member of the Mauch Chunk Formation, Corridor H, West VirginiaApr 23, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 93584 x 78952 pixelsMarine incursion (transgression) sandwiched between redbeds. | Cretaceous strata at Swift DamApr 29, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 31991 x 24418 pixelsBelow the thrust, contorted shale and sandstone | The French Thrust, Sun River Canyon, MontanaApr 29, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 68736 x 38240 pixelsA Sevier-style thrust fault exposed west of Augusta, Montana, the French Thrust has emplaced Mississippian carbonates on top of Cretaceous shales. On the left (east), there is also some till, outwash, and colluvium. View is approximately to the south. | Swift Dam anticline, looking westApr 29, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 54336 x 26176 pixelsYou're looking down the nose of this overturned anticline of Mississippian carbonate. Search for fossil coral heads and extensional fractures on the outside edge of this giant Sevier-aged thrust.
For a (partial) view from the side, you can check out this gigapan:
https://viewer.gigamacro.com/view/uyCmBJ2HE9AndfqC
For a blog post talking about the geology here, see:
http://blogs.agu.org/mountainbeltway/2011/07/25/swift-dam/ | Leptaena brachipod in fossiliferous limestoneApr 28, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 37856 x 33664 pixelsFossiliferous limestone of the Madison Group, collected from talus in Sacagawea Cirque, Bridger Range, Montana.
The obverse of this sample, rich in fenestrate bryozoans, can be seen here: https://viewer.gigamacro.com/view/GPmEuy1i8c0JynKE | Bryozoan-rich limestoneApr 28, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 38516 x 34592 pixelsMississippian-aged Madison Group limestone, Bridger Range, Montana.
Obverse of this sample: https://viewer.gigamacro.com/view/YZX4IDmiyQCmk5Yn | Old Red Sandstone, headland at Dunbar, ScotlandApr 20, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 37556 x 11080 pixelsPrimary sedimentary structures are visible. Interpret the environment of deposition. Interpret the geologic history subsequent to deposition. | Conemaugh Formation sandstoneApr 21, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 45688 x 35580 pixelswith cross-beds and pebbles. Corridor H, West Virginia.
Flip side of the sample here: https://viewer.gigamacro.com/view/WRz0Oxey7GZtiihK | LepidodendronApr 30, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 54124 x 39912 pixelsCarboniferous-aged fossil bark from Debiensko Coal Mine in Poland's Upper Silesia Coal Basin. Bark shows parichnos (scars of leaf attachments to stem). | Fossils in Reynolds Limestone, Mauch Chunk FormationApr 23, 2020 by magic-gigapansImage: Marissa Dudek, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 34552 x 24904 pixelsLate Mississippian aged brachiopod and snail fossils within Reynold limestone of the Mauch Chunk Formation east of Bismark, West Virginia along Corridor H. You can view a GigaPan of the full outcrop that Joshua Benton did here: https://viewer.gigamacro.com/view/Lxqp87KurGyG0L8i | S-C myloniteApr 10, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 36460 x 17444 pixelsMylonite developed a dextral strike-slip fault of the 4 km wide Brookneal shear zone in the southwest Virginia Piedmont. The shear zone is, in part, superimposed on the Melrose Granite where an SC mylonite (this sample) was produced by dynamic recrystallization of all constituent minerals. The age of movement on the Brookneal shear zone has been constrained by isotopic dating to between 324 and 300 Ma.
Learn more here: http://adsabs.harvard.edu/abs/1986Tecto...5..119G
Sample from the structural geology teaching collection of Carol Simpson and Declan De Paor. | Mauch Chunk Formation, showing Reynolds Limestone MemberApr 24, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 161856 x 22544 pixelsA fantastic exposure of Mississippian aged strata on Corridor H, showing a transgression and ensuing regression. | Coal, Conemaugh Formation, Corridor H, West VirginiaApr 10, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 47184 x 27679 pixelsNear Bismarck, West Virginia, on the eastern edge of the Alleghany Plateau, is an outcrop of Pennsylvanian coal, shale, and sandstone called "The Dragon's Tongue." This sample comes from there. Read more about the site here: http://blogs.agu.org/mountainbeltway/2015/08/14/paleoslump-features-and-fluvial-incision-in-the-conemaugh-group-west-virginia/ | Faults in Fort Payne Formation, KentuckyMar 25, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 64917 x 20045 pixelsNormal faults offsetting shale and carbonate grainstone layers in the Fort Payne Formation NNW of Burkesville, Kentucky. | Conemaugh Formation sandstoneApr 21, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 38296 x 33184 pixelsWith pebbles and cross-beds.
Flip side of the sample here: https://viewer.gigamacro.com/view/oN2CYrfY1y8zqLJ3 | Coal and pyrite from the Carboniferous PeriodApr 24, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 16716 x 18988 pixelsCoal and pyrite from the lowermost Mississippian strata on Corridor H.
The roadcut from which this sample was collected can be seen here:
https://viewer.gigamacro.com/view/mtVNT3OO1X070akn | Giant eurypterid trackway near St. Andrews, ScotlandApr 20, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 31560 x 19324 pixelsAn incredibly large trace fossil - site where a very large eurypterid crawled through the sand during the early Mississippian (~340 to ~320 Ma).
Geolocation is intentionally imprecise to protect the site. | East Sheep Canyon - Sheep Mountain Anticline, WYApr 29, 2020 by magic-gigapansImage: Jeffrey Rollins, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 56712 x 20756 pixels44.615818, -108.132180 - Facing Southwest
Sheep Canyon has been cut by the Bighorn River perpendicular to the axis of the Sheep Mountain Anticline, which runs NW –SE. Anticlines are defined as folds having the oldest rock units exposed at their core, so as one looks from left to right across this panorama they are essentially looking back in time through the depositional record in this area from the Triassic Chugwater Formation (The bright red siltstone to the far left) to the Mississippian Madison Limestone (Massive tan limestone to the right). This is an excellent display of the anticline’s steep forelimb: strata are folded from near horizontal to roughly 60 degrees to the northeast.
To view Sheep Canyon from the west, click here:
https://viewer.gigamacro.com/view/bQwVukWu0ZTbQoEE
To view The Nose, click here:
https://viewer.gigamacro.com/view/gWaeR06Z5u8SA7eM | Plant fossil: gymnospermApr 15, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 40800 x 26496 pixelsStem with needles, or a raggedy cone (?), Conemaugh Formation, Corridor H. | "Dunbar Marble": Mississippian limestone chock full of rugose coralsApr 20, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 27820 x 9896 pixelsFound cropping out along the beach at Barns Ness, east of Dunbar, Scotland. | Two sections through a folded sandstone slab ("ploudin") from the mass transport deposit at the end-Devonian section on Corridor H, West VirginiaMar 31, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 66712 x 38660 pixelsSource outcrop is a mass transport deposit in the Devonian-to-Mississippian sedimentary succession exposed on Corridor H, West Virginia, just east of the easternmost Alleghany Plateau.
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Explore a GigaPan of the outcrop here:
https://viewer.gigamacro.com/view/My1WrrbRaK3byzTk
Two thin sections through one of these "ploudins" can be seen here:
...(1)
PPL: https://viewer.gigamacro.com/view/02upCYeZX9hGttxG
XPL: https://viewer.gigamacro.com/view/OPiGyaavAWhQgJzq
...(2)
PPL: https://viewer.gigamacro.com/view/EOKFi1hMBfAht7Eg
XPL: https://viewer.gigamacro.com/view/q1qKxltQNEn6Misp | Marine body fossils in Mississippian-aged Reynolds LimestoneMar 31, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 37056 x 20116 pixelsClick here to explore the cut and polished side of this sample:
https://viewer.gigamacro.com/view/aIPjlhK8P9mQ6Cbn | Fern fossil, St. Clair, PennsylvaniaMay 4, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 36000 x 47092 pixelsLlewellyn Formation, latest Pennsylvanian (the time period) of eastern Pennsylvania (the state).
https://en.wikipedia.org/wiki/Llewellyn_Formation | Old Red Sandstone, cliff at Dunbar, ScotlandApr 20, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 55656 x 21356 pixelsPrimary sedimentary structures are visible. Interpret the environment of deposition. Interpret the geologic history subsequent to deposition. | Brachiopods and crinoid stems in Mississippian-aged Reynolds LimestoneMar 31, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 36044 x 27688 pixelsClick here to explore the obverse of this sample:
https://viewer.gigamacro.com/view/837y0s0sxZYJX5Cq | Giant eurypterid trackway, near St. Andrews, ScotlandApr 20, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 47188 x 27036 pixelsAn incredibly large trace fossil - site where a very large eurypterid crawled through the sand during the early Mississippian (~340 to ~320 Ma).
Geolocation is intentionally imprecise to protect the site. | Coal Bed, Corridor H, West VirginiaApr 24, 2020 by magic-gigapansImage: Marissa Dudek, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 35224 x 12620 pixelsBed of coal along Corridor H, east of Bismark, West Virginia. | "Dragon's Tongue" Outcrop, Corridor H, West VirginiaApr 23, 2020 by magic-gigapansImage: Jeffrey Rollins, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 50608 x 7036 pixels39*12'46'' N / 79*15'50'' W - Facing North
Conemaugh Group outcropping along Corridor H in West Virginia, showing slump blocks and channel scour and fill. |
