1. Skip to navigation
  2. Skip to content
  3. Skip to sidebar


Callan Bentley's Snapshots

Go to page:
  1. Scale

    Snapshot Title: Scale
    Taken by: Callan Bentley

    Image: Graded Bedding in the Martinsburg Formation
    Image Owner: Robin Rohrback



    Description:

    1 cm



  2. Scale

    Snapshot Title: Scale
    Taken by: Callan Bentley

    Image: Giant Fusulinids
    Image Owner: Robin Rohrback



    Description:

    This blue bar is 1 cm across.



  3. Schwagerina, a fusilinid foram

    Snapshot Title: Schwagerina, a fusilinid foram
    Taken by: Callan Bentley

    Image: Giant Fusulinids
    Image Owner: Robin Rohrback



    Description:

    Cross-sectioned, with overall spiral shape and internal subdivisions visible.



  4. Cribratina

    Snapshot Title: Cribratina
    Taken by: Callan Bentley

    Image: Cribratina duo
    Image Owner: Callan Bentley



    Description:

    This foram is an index fossil for the Albian age.



  5. Scale

    Snapshot Title: Scale
    Taken by: Callan Bentley

    Image: Cribratina duo
    Image Owner: Callan Bentley



    Description:

    This blue bar is 1 cm long.



  6. Trilobite shell

    Snapshot Title: Trilobite shell
    Taken by: Callan Bentley

    Image: Storm deposit in Reedsville Formation
    Image Owner: Callan Bentley



    Description:

    in cross-section



  7. Scale

    Snapshot Title: Scale
    Taken by: Callan Bentley

    Image: Storm deposit in Reedsville Formation
    Image Owner: Callan Bentley



    Description:

    This blue box is a 1 cm long scale bar.



  8. Cave

    Snapshot Title: Cave
    Taken by: Callan Bentley

    Image: Conococheague Formation exposed near Mulberry Run, Virginia
    Image Owner: Callan Bentley



    Description:

    Little cave, spewing red clay



  9. stromatolite

    Snapshot Title: stromatolite
    Taken by: Callan Bentley

    Image: Conococheague Formation exposed near Mulberry Run, Virginia
    Image Owner: Callan Bentley



    Description:

    algal mound



  10. Pen for scale

    Snapshot Title: Pen for scale
    Taken by: Callan Bentley

    Image: Conococheague Formation exposed near Mulberry Run, Virginia
    Image Owner: Callan Bentley



    Description:

    A typical ballpoint pen, to help you calibrate your sense of scale.



  11. Rip-ups

    Snapshot Title: Rip-ups
    Taken by: Callan Bentley

    Image: Grinnell Formation Quartzite
    Image Owner: Robin Rohrback



    Description:

    What do these mud-chip rip-up clasts suggest about the depositional energy (current strength) at this site over time?



  12. O2

    Snapshot Title: O2
    Taken by: Callan Bentley

    Image: Grinnell Formation Quartzite
    Image Owner: Robin Rohrback



    Description:

    Were these sediments deposited under oxygenated or anoxic conditions? What evidence supports your conclusion?



  13. Crossbeds

    Snapshot Title: Crossbeds
    Taken by: Callan Bentley

    Image: Grinnell Formation Quartzite
    Image Owner: Robin Rohrback



    Description:

    Is the sample right-side-up or up-side-down? How do you know? Which way was the sediment-depositing current flowing when these grains were laid down? What evidence would you cite in support of your in...



  14. Mudchips & crossbeds

    Snapshot Title: Mudchips & crossbeds
    Taken by: Callan Bentley

    Image: Grinnell Formation Quartzite
    Image Owner: Robin Rohrback



    Description:

    Which way was the current flowing? How had the depositional energy changed?



  15. 1 cm

    Snapshot Title: 1 cm
    Taken by: Callan Bentley

    Image: Grinnell Formation Quartzite
    Image Owner: Robin Rohrback



    Description:

    This scale bar conveys a sense of how big the rock sample is. The blue bars are each 1 centimeter wide.



  16. Sutured grain boundary

    Snapshot Title: Sutured grain boundary
    Taken by: Callan Bentley

    Image: Flat Pebble Conglomerate, Gros Ventre Formation
    Image Owner: Robin Rohrback



    Description:

    Evidence of pressure solution



  17. 120 degree fractures

    Snapshot Title: 120 degree fractures
    Taken by: Callan Bentley

    Image: Flat Pebble Conglomerate, Gros Ventre Formation
    Image Owner: Robin Rohrback



    Description:

    Some of the pebbles are cracked due to bedding-perpendicular loading and bedding-parallel extension. σ1 > σ2 = σ3



  18. 1 cm

    Snapshot Title: 1 cm
    Taken by: Callan Bentley

    Image: Flat Pebble Conglomerate, Gros Ventre Formation
    Image Owner: Robin Rohrback



    Description:

    This bar serves as a sense of scale.



  19. Scale

    Snapshot Title: Scale
    Taken by: Callan Bentley

    Image: Massanutten Sandstone
    Image Owner: Callan Bentley



    Description:

    This pencil serves as a sense of scale. The black bars along its side are each 1 cm in length.



  20. Scale

    Snapshot Title: Scale
    Taken by: Callan Bentley

    Image: Massanutten Sandstone
    Image Owner: Callan Bentley



    Description:

    This pencil serves as a sense of scale. The black bars along its side are 1 cm in length each.



  21. Scale

    Snapshot Title: Scale
    Taken by: Callan Bentley

    Image: Massanutten Sandstone
    Image Owner: Callan Bentley



    Description:

    This pencil serves as a sense of scale. The black bars on its side are each 1 cm long.



  22. Blocky "needles"

    Snapshot Title: Blocky "needles"
    Taken by: Callan Bentley

    Image: Stylolite in Helderberg Group limestone, West Virginia
    Image Owner: Callan Bentley



    Description:

    Stylolitic surface in detail. Note apparent accumulation of clay (pelitic non-soluble material) along stylolite surface.



  23. Stylolite "needle"

    Snapshot Title: Stylolite "needle"
    Taken by: Callan Bentley

    Image: Stylolite in Helderberg Group limestone, West Virginia
    Image Owner: Callan Bentley



    Description:

    Rock has dissolved along this surface, causing interpenetration of the two strata.



  24. Fossil

    Snapshot Title: Fossil
    Taken by: Callan Bentley

    Image: Stylolite in Helderberg Group limestone, West Virginia
    Image Owner: Callan Bentley



    Description:

    Shelly material



  25. 1 cm

    Snapshot Title: 1 cm
    Taken by: Callan Bentley

    Image: Stylolite in Helderberg Group limestone, West Virginia
    Image Owner: Callan Bentley



    Description:

    Scale



  26. Sandstone pebble

    Snapshot Title: Sandstone pebble
    Taken by: Callan Bentley

    Image: Shawangunk Conglomerate, Pennsylvania
    Image Owner: Callan Bentley



    Description:

    You can see the grains inside it.



  27. Flush grain boundaries

    Snapshot Title: Flush grain boundaries
    Taken by: Callan Bentley

    Image: Shawangunk Conglomerate, Pennsylvania
    Image Owner: Callan Bentley



    Description:

    Evidence of pressure solution



  28. 1 cm

    Snapshot Title: 1 cm
    Taken by: Callan Bentley

    Image: Shawangunk Conglomerate, Pennsylvania
    Image Owner: Callan Bentley



    Description:

    Scale



  29. Phenocryst

    Snapshot Title: Phenocryst
    Taken by: Callan Bentley

    Image: Bishop Tuff
    Image Owner: Robin Rohrback



    Description:

    Quartz (note the conchoidal fracture).



  30. Lithic

    Snapshot Title: Lithic
    Taken by: Callan Bentley

    Image: Bishop Tuff
    Image Owner: Robin Rohrback



    Description:

    Fragment of pre-existing rock, caught up in the pyroclastic surge.



  31. Scale

    Snapshot Title: Scale
    Taken by: Callan Bentley

    Image: Bishop Tuff
    Image Owner: Robin Rohrback



    Description:

    This box is 1 cm wide.



  32. Sample

    Snapshot Title: Sample
    Taken by: Callan Bentley

    Image: Rockfish Gap, Virginia
    Image Owner: Callan Bentley



    Description:

    To see a piece of the Catoctin greenstone from this site in "macro" GigaPan view, click here: gigapan.com/gigapans/149431



  33. Sample

    Snapshot Title: Sample
    Taken by: Callan Bentley

    Image: Rockfish Gap, Virginia
    Image Owner: Callan Bentley



    Description:

    To see a piece of the Catoctin greenstone from this site in "macro" GigaPan view, click here: gigapan.com/gigapans/149431



  34. 1 cm Scale

    Snapshot Title: 1 cm Scale
    Taken by: Callan Bentley

    Image: Chip suite, El Paso region geology
    Image Owner: Callan Bentley



    Description:

    This box is 1 centimeter across



  35. Partly lithified cluster

    Snapshot Title: Partly lithified cluster
    Taken by: Callan Bentley

    Image: Coarse Ooids
    Image Owner: Robin Rohrback



    Description:

    oolitic limestone in the making.



  36. Pyrite

    Snapshot Title: Pyrite
    Taken by: Callan Bentley

    Image: Flat Pebble Conglomerate, Gros Ventre Formation
    Image Owner: Robin Rohrback



    Description:

    Small pyrite crystal, surrounded by a rusty aura.



  37. Scale

    Snapshot Title: Scale
    Taken by: Callan Bentley

    Image: Ball and pillow
    Image Owner: Callan Bentley



    Description:

    This is 1 cm long.



  38. Sample collected here

    Snapshot Title: Sample collected here
    Taken by: Callan Bentley

    Image: Ball and pillow
    Image Owner: Callan Bentley



    Description:

    :)



  39. Square hole

    Snapshot Title: Square hole
    Taken by: Callan Bentley

    Image: Mudcracks from the Belt Supergroup
    Image Owner: Robin Rohrback



    Description:

    Suspiciously square shaped... former halite cast? or just geo-pareidolia?



  40. Book return

    Snapshot Title: Book return
    Taken by: Callan Bentley

    Image: Fort Valley Community Center and Library
    Image Owner: Callan Bentley



    Description:

    Drop box!



Go to page: