30+ Thin Section Photos That Will Develop Your Interest In Petrography

The art of getting ready thin sections has been critical to expertise the core samples that scientists are observing. Thin segment samples permit scientists to look at minerals in rocks, their crystal shape and texture at a microscopic stage. Want to revise how do geologists examine rock? Follow this hyperlink to see our blog on "Studying Rock". In this blog, we're taking you into the adventure of thin phase snap shots that were captured and given by means of college students and younger professionals from Finland, Ireland, Denmark, Czech Republic and Plymouth (UK). Again our purpose is to encourage students and professionals' research by promoting "learning and scope" of Geology through our blogs. Help us to help others in learning and understanding geology. See this link that how you can contribute to Learning Geology. Note: We are using following thin section photos by having permission from their owners. If you like to use these photos, leave us a message or email ushere. 1. A beautiful heart shaped hornblende in XPL (cross polarized light) view.It is a thin section ofbasalt with some secondary mineralization in the vesicles. Plagioclase is present in the form of black and white matrix and large phenocryst (with some zoning). Alignment of plagioclase grains is indicative of the "flow" of magma. Photo Credits: Astaley 2. Thin Section of a Biotite and Muscovite, XPL view Photo Courtesy: Laura 3. Thin Section of a Plagioclase (orthoclase) and Pyroxene, XPL Photo Courtesy: Laura 4. Eclogite in Thin Section, XPL Photo Courtesy: Laura 5. Cummulate Rock with Pyroxene and plagioclase, XPL Photo Courtesy: Laura 6. Blueschist, XPL Photo Courtesy: Laura 7. Agglomerate in a Thin Section, XPL view        Agglomerates are pyroclastic igneous rocks that consist almost wholly of angular or rounded lava fragments of varying size and shape. Fragments are usually poorly sorted in a tuffaceous matrix, or appear in lithified volcanic ash. (Britannica.com) Photo Courtesy: Laura 8. Thin Section of a Pigeonite and Olivine, XPL Photo Courtesy: Laura nine. Olivine phenocryst in Basaltic Lapilli, XPL Photo Courtesy: Laura 10. Thin Section of a Gabbro, XPL Showing minerals; Pyroxene and Olivine, plagioclase and others. Learn more about Gabbrohere. Photo Courtesy: Laura  11. Another beautiful skinny section of a Gabbro, XPL Photo Courtesy: Laura 12. Thin Section of a Greenschist, XPL Photo Courtesy: Laura thirteen. Thin Section showing intrusion of rocks from magma chamber into united states rocks, XPL Photo Courtesy: Jack Lewis Donnelly 14. Thin Section of a Sillimanite - a mineral discovered in rocks formed with the aid of the metamorphism of a mudstone. (XPL view) Photo Courtesy: Jack Lewis Donnelly 15. Microgeode in ultrabasic vulcanite (a rare copper telluride mineral), 30 µm thin section, PPL and XPL Photo Courtesy: Petr Hyks Photo Courtesy: Petr Hyks See unique photohere 16. Muscovite & biotite (30 µm thin section, PPL and XPL) Photo Courtesy:Petr Hyks Photo Courtesy:Petr Hyks Same photo in XPL view. See unique photohere 17. Quartz and epidote (30 µm thin section, PPL and XPL) Photo Courtesy:Petr Hyks Photo Courtesy:Petr Hyks See originalhere. 18. Olivine (30 µm thin section, PPL and XPL) Photo Courtesy: Petr Hyks See this photohere on Petr Hyks' website 19. Zircons in biotite (30 µm thin section, PPL views, showing extinction)                           Photo Courtesy:Petr Hyks See this photo here on Petr's website 20. Zircon in biotite (30 µm thin section, XPL) Photo Courtesy:Petr Hyks See this photo here on Petr's situs web 21. Kyanite surrounded by muscovite (30 µm thin section, PPL and XPL) Photo Courtesy: Petr Hyks See these photos on Petr's pagehere and here 22. Zircon crystal in chloritized biotite (30 µm thin section, PPL and XPL) Photo Courtesy:Petr Hyks See these photos on Petr's pagehere and here Petr Hyks is 21 year old geology student from Masaryk University in Brno (Czech Republic). He has uploaded 5000+ photos about geology, astronomy and meteorology on his Flickr page. Follow this link to visit his situs web. Thank you Petr for contributing to Learning Geology and helping others to learn geology through your thin section photos. 🙂 Now following 10 thin section photos are from a geology student of University of Helsinki, Finland. 23. Thin Section of Olivine Diabase in XPL and PPL view. Photo Courtesy: GeoAmethyst 24. Thin Section of Basalt in XPL view         Having minerals: Olivine (in center) plagioclase, pyroxene and other accessory minerals Photo Courtesy:GeoAmethyst 25. Thin Section of a Trachyte, XPL view     Trachyte is an igneous volcanic rock with aphanitic to porphyritic texture. It is volcanic equivalent of Syenite. Major or essential minerals are alkali feldspar with less amount of plagioclase, quartz or feldspathiod. Photo Courtesy:GeoAmethyst 26. Thin Section of a Harzburgite, XPL view       Harzburgite is an ultramafic igneous rock. It chiefly contains plagioclase (under 10%) , olivine, orthopyroxene (enstatite), clinopyroxene (diopside) and biotite. There could be a small amount of talc, carbonate, tremolite, cummingtonite, chlorite, serpentine and titanite. Photo Courtesy:GeoAmethyst 27.  Another thin section of Harzburgite, XPL view Photo Courtesy:GeoAmethyst 28.  Thin Section of Pyroxenite (an ultramafic igneous rock), XPL view Photo Courtesy:GeoAmethyst 29. Thin Section of Trachyte showing Sandine mineral in center, XPL view Photo Courtesy:GeoAmethyst 30.  Thin Section of Andesite, XPL view        It is an extrusive igneous, of intermediate composition, with aphanitic to porphyritic texture.              Here this thin section is showing chiefly hornblende and plagioclase. Photo Courtesy:GeoAmethyst 31. Thin Section of Alkali Basalt (silica undersaturated) in XPL view. Photo Courtesy:GeoAmethyst 32. Thin Section showing small clinopyroxene grains within orthopyroxene Photo Courtesy:GeoAmethyst Like this article? Leave a comment down or send us your valuable suggestion or feedback here  to help us in improving this article. Useful Websites:  1. Polarized light Microscopy (Image Gallery) 2.How to make a thin section 3. Petrographic thin section preparation 4. Guide to Thin Section Microscopy 5. Index of Minerals in Thin Section 6. Optical Petrography website by an Italian Geologist 7.Carbonate Thin Section Images and Exercises
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Igneous Origin Of Diamonds

Diamonds are a rare occurrence on the surface of the planet because it takes extremely hot and high pressure conditions to create them. Physical and chemical conditions where diamonds form only exist in the mantle, nearly 70 miles down or more. In that environment in the upper mantle, diamonds may be a common mineral! It takes incredible events, nothing that has ever been witnessed in historic times, to bring diamonds to the surface. Kimberlite-Diamond-mantle-rock Diamond deposits around the world (that have any economic significance) are associated with volcanic features called diatremes.  A diatreme is a long, vertical pipe formed when gas-filled magma forces its way through the crust to explosively erupt at the surface. Kimberlite  a special kind of intrusive igneous rock associated with some diatremes that sometimes contain diamonds, typical coarse grained an bluish in color. Diamond-bearing kimberlite pipes are diatremes that originate in the mantle. Diamonds are xenoliths  carried up from deep sources in the mantle, and often occur in association with other gem minerals including garnet , spinel and diopside . Most "economically significant" diamond deposits occur in ancient rocks (Precambrian age), but have been discovered on all continents. Because diamonds are so hard, they survive torturously-long histories, recycled through sedimentary and metamorphic environments without being destroyed. As a result they have been found almost everywhere as very rare, isolated discoveries. Diamonds of microscopic size have been discovered in meteorites and asteroid impact sites, and some metamorphic rocks. They are most extensively mined from kimberlite pipes or from alluvial gravels derived downstream from diamond source areas. It should be noted that most diamonds are not of gem quality , but those that are not are used for industrial purposes. Credits to Phil Stoffer at geologycafe.Com Text and figures are used with permission.
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