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. | Fagopsis leafMay 4, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 15388 x 13332 pixelsFagopsis leaf, courtesy of Joseph Cancellare of El Paso Community College. | Eocene-aged fish from the Green River FormationMay 13, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 17944 x 18692 pixelsAn Eocene-aged fish from the Green River Formation in Wyoming. This sample was provided by Dr. John Merck of the Univeristy of Maryland. | 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 | Graptolite fossils from Dobb's Linn, ScotlandApr 9, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 44773 x 38352 pixelsThe tools used to figure out the stratotype for the Ordovician/Silurian boundary. | Zoophycos trace fossils in Mahantango FormationMay 5, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 25284 x 17948 pixelsDevonian sediment-mining feeding traces preserved in Devonian-aged mudrock, Fort Valley, Virginia. | GraptolitesMar 30, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 57468 x 25231 pixelsDissolved with acid from a rock deposited in a gutter cast near Cincinatti.
From Russ Kohrs | GlossopterisMay 1, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 16476 x 15248 pixels | Diatomaceous earthApr 30, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 6676 x 8195 pixelsDiatoms in the SEM. | 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 | Stromatolites in Helena (Siyeh) Formation limestone from Alberta, CanadaApr 29, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 24320 x 48364 pixelsStromatolites in the Helena (Siyeh) Formation limestone, which is part of the Mesoproterozoic-aged Belt Supergroup. | 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 | Brachiopods and bivalve mollusksMay 6, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 24132 x 15524 pixels | Petrified wood cross sectionMay 4, 2020 by magic-gigapansImage: Marissa Dudek, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 20612 x 22052 pixelsPetrified tree trunk outside of the Smithsonian Natural History Museum in Washington, D.C.
Two hundred and seven million year old conifer (Araucarioxylon arizonicum) from the Triassic period found in today's Petrified Forest National Park in Arizona.
Approximately two feet in diameter. | Graded carbonate bedsMay 7, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 23872 x 20460 pixelsGraded carbonate beds from a forereef in the Guadalupe Mountains. | Stromatolites, Helena Formation, near Crypt Lake, Waterton Lakes National Park, AlbertaMay 11, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 18105 x 15194 pixelsSlab of limestone showing stromatolites. | Ulster White Limestone ("The Chalk") with belemnite fossil, Rathlin Island, Northern Ireland (U.K.)Apr 15, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 24145 x 21308 pixelsA cross-section through a belemnite fossil can be seen in the Cretaceous white limestone exposed on Rathlin Island below voluminous outpourings of Causeway basalts.
Rathlin Island, Northern Ireland, U.K.
Obverse of the sample: https://viewer.gigamacro.com/view/nVrw5688fO3lxich | Bryozoan-rich limestoneMar 25, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 40144 x 30160 pixelsCincinnatian limestone collected near Maysville, Kentucky. Filled with a plethora of storm-winnowed crinoid, trilobite, and bryozoan parts. | Sphalerite on Fossiliferous ChertApr 8, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 20308 x 14824 pixelsSphalerite cyrstals on fossiliferous chert from Cherokee County, OK.
Click here to explore three small hand samples of sphalerite:
https://viewer.gigamacro.com/view/qxeALZsDGTdLpSbD
Click here for a video of sphalerite
rotating in plane polarized light:
https://youtu.be/3urV6muuQOs
Click here for a video of sphalerite rotating in cross polarized light:
https://youtu.be/h4vTVQOcEWk
This sample was graciously donated by David and Leslie Nanney. | Healed break in hadrosaur boneMay 1, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 22288 x 14512 pixels | 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). | Stromatolites and ooids in banded iron formationMay 1, 2020 by magic-gigapansImage: Callan Bentley, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 24012 x 23072 pixelsA lively scene from shallow water sometime in the late Archean or Paleoproterozoic. This is Biwibik Iron Formation. It is a sample purchased from Ward's Scientific, which identifies it as hailing from Keweenawan, Michigan, USA. Biwibik itself is in Minnesota, though. The label identifies the stromatolite form (species??) as Collenia. | 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 | Ridgeley SandstoneApr 30, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 32836 x 27084 pixelsBrachiopod and gastropod body fossils from a little spit of Ridgeley Sandstone surrounded by Keyser Limestone in LaVale, MD. The small concentric structures are beekite rings.
To explore the outcrop from which this sample was collected, click here: https://viewer.gigamacro.com/view/7WjtxcmEzsjmOzwg | Ostracodes and brachiopods in Tonoloway Formation limestoneMar 31, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 16576 x 12948 pixelsClick here to explore the obverse of this sample:
https://viewer.gigamacro.com/view/R6nJIqR4a1FtKyOF | Storm deposits in Tonoloway Formation limestoneMay 5, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 25384 x 21032 pixelsWhich way is up?
Ancient storms recorded in Tonoloway limestone exposed in the northwest wall of the "Old Derrick" Quarry, along Rt. 50, near Romney, WV.
The quarry's late Silurian-aged peritidal carbonates were laid down in the Tippecanoe sea. Its strata primarily record a tidal flat environment, with conspicuous mudcracks, laminites, stromatolites, and salt hoppers within the micritic sediment.
Interspersed with these features are coarse layers of lagoonal bioclastics, such as ostracodes and small brachiopods, flung across the flats by passing storms.
The quarry from which this was collected:
https://viewer.gigamacro.com/view/ziGPpgw3nz4pvqZV
https://viewer.gigamacro.com/view/CgkCWIfXyzmefpPW | EncriniteMar 30, 2020 by magic-gigapansImage: Robin Rohrback, Mid-Atlantic Geo-Image CollectionSubject: Subject ID: 16480 x 15152 pixelsClick here to explore a thin section of encrinite in plane polarized light:
https://viewer.gigamacro.com/view/brIahdyOXO4UFJRE
Click here to explore a thin section of encrinite in cross polarized light:
https://viewer.gigamacro.com/view/aIR6Z1A2y8ueouHd |
