File:Kimberlite from the Jurassic of Pennsylvania.jpg
Original file (2,639 × 1,862 pixels, file size: 4.36 MB, MIME type: image/jpeg)
Captions
Captions
Summary
edit
| Description |
English: Kimberlite from the Jurassic of Pennsylvania, USA. (~4.6 cm across at its widest)
Kimberlites and lamproites have tremendous economic importance because they are host rocks for gem-grade and industrial-grade diamonds. Kimberlites & lamproites are unusual igneous bodies having overall pipe-shaped geometries. Their mode of formation is only moderately understood because they have not been observed forming. Kimberlites & lamproites are known from scattered localities throughout the world - only some are significantly diamondiferous. Classic localities for diamonds are India and Brazil. Africa was also discovered to have many kimberlites and is world-famous for producing large numbers of diamonds. Other notable diamondiferous kimberlite-lamproite occurrences include Russia, China, northwestern Australia, and northwestern Canada. Kimberlites are named for the town of Kimberley, South Africa. Several kimberlite pipes occur in the Kimberley area. Kimberlites have a gently tapering-downward, pipe-shaped cross-section. Lamproites have a cross-section more closely resembling that of a martini glass. The rock shown above is from a non-diamondiferous kimberlite intrusion in Pennsylvania. Unlike most kimberlites, which have pipe-shaped geometries, this occurrence is an igneous dike. The groundmass consist of olivine, phlogopite mica, and opaque minerals. Phenocrysts and megacrysts reported from this unit include olivine (serpentinized) and pyrope garnet. Geologic unit: Gates-Adah Kimberlite Dike, middle Early Jurassic, 185 Ma Locality: Gates-Adah Kimberlite Dike trend, near Middle Run, east of the Monongahela River, north or northeast of the town of Gates, far-western Fayette County, southwestern Pennsylvania, USA |
| Date | |
| Source | Kimberlite (Gates-Adah Kimberlite Dike, Early Jurassic; Fayette County, Pennsylvania, USA) 2 |
| Author | James St. John |
Licensing
edit
- 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@N05/31486909736. It was reviewed on 9 December 2016 by FlickreviewR 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 | 13:27, 9 December 2016 | | 2,639 × 1,862 (4.36 MB) | DonRumata (talk | contribs) | {{Information |Description ={{en|1=Kimberlite from the Jurassic of Pennsylvania, USA. (~4.6 cm across at its widest) Kimberlites and lamproites have tremendous economic importance because they are host rocks for gem-grade and industrial-grade diamo... |
You cannot overwrite this file.
File usage on Commons
The following page uses this file:
_2_(31486909736).jpg&redirect=no){kind=link}
File usage on other wikis
The following other wikis use this file:
- Usage on ru.wiktionary.org
