File:Fault in ribbon cherts (Franciscan Complex, Lower Jurassic-Lower Cretaceous; southern Marin Peninsula, San Francisco Bay, California, USA) 8.jpg
Original file (3,008 × 2,000 pixels, file size: 5.36 MB, MIME type: image/jpeg)
Captions
Captions
Summary[edit]
_8.jpg&action=edit§ion=1){kind=link}
| Description |
English: Radiolarian ribbon cherts in the Mesozoic of California, USA.
These rocks are tectonically tilted layers of chert. The dark brick-red color is from hematite (Fe2O3 - iron oxide). Weathering of these chert beds results in a ribbon-like appearance, hence the term ribbon chert. Chert is a siliceous sedimentary rock, composed of cryptocrystalline quartz (SiO2). These particular cherts have abundant microfossils of radiolarians, a group of marine, unicellular, non-photosynthesizing protists that make tiny skeletons of opal (SiO2·nH2O). Burial and diagenesis of radiolarian-rich sediments results in the formation of radiolarian cherts. These rocks are part of the Franciscan Complex (Jurassic) and were deposited on an ancient deep seafloor. The rocks got scraped from the top of a subducting slab of oceanic crust (the Farallon Plate) along coastal California. The lower-left-to-upper-right fracture in the rocks that offsets the bedding is a fault. Locality: roadcut in the southern Marin Peninsula, Golden Gate National Recreation Area, north of San Francisco, western coast of California, USA |
| Date | |
| Source | https://www.flickr.com/photos/47445767@N05/40296970673/ |
| Author | James St. John |
Licensing[edit]
_8.jpg&action=edit§ion=2){kind=link}
- You are free:
- to share – to copy, distribute and transmit the work
- to remix – to adapt the work
- Under the following conditions:
- attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
|
This image was originally posted to Flickr by James St. John at https://flickr.com/photos/47445767@N05/40296970673. It was reviewed on 2 December 2020 by FlickreviewR 2 and was confirmed to be licensed under the terms of the cc-by-2.0. |
File history
Click on a date/time to view the file as it appeared at that time.
| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 15:38, 2 December 2020 | | 3,008 × 2,000 (5.36 MB) | Ser Amantio di Nicolao (talk | contribs) | Uploaded a work by James St. John from https://www.flickr.com/photos/47445767@N05/40296970673/ with UploadWizard |
You cannot overwrite this file.
File usage on Commons
There are no pages that use this file.
_8.jpg&oldid=689007914){kind=link}