Learn about the variety of crystalline textures with me! In this video, I first recap the difference between detrital and crystalline textures. Then, I go over crystalline texture terminology (size terms for crystalline rocks (cryptocrystalline, microcrystalline, mesocrystalline, or macrocrystalline), clast terms (porphyroblasts vs poikiloblasts) crystal grain shape terms (euhedral, subhedral, and anhedral), and grain boundary terms (straight, curved, embayed, scalloped or cuspate, & sutured grain boundaries). Then regarding cement fabrics or textures, I clarify the difference between sedimentary diagenesis and metamorphism, and then show examples of the crystalline textures present in cements (drusy, fibrous, blocky, etc.). Then, I touch on recrystallization fabrics and the minerals commonly involved (aragonite, calcite), and replacement fabrics or textures, where we focus on how to determine relative ages of chemical precipitates in rocks. For example, euhdral crystal grains form first and subhedral and anhedral crystals fill the interstices between euhedral grains. Unfortunately, that isn't always the case, and I discuss an exception to this rule in the video. Next that brings us to the common texture of vein fillings, which are typically minerals gypsum, calcite, quartz, or a combination of these, and have fibrous textures that grow from the vein walls inward, just like cement grows from grain edges inward into the void space. Lastly, I cover the difference between oolites and pisolites, why peloids are often called pseudo-oolites, the radial structure and textures of ooids and how it can change if recrystallized or replaced, and the difference between oolites and spherulites.

References: Sedimentary Rocks by Pettijohn: [ Ссылка ]
Sedimentology and Stratigraphy by Boggs: [ Ссылка ]

GEO GIRL Website: [ Ссылка ] (visit my website to see all my courses, shop merch, learn more about me, and donate to support the channel if you'd like!)

0:00 video outline
0:43 detrital vs crystalline textures
2:16 crystalline texture terminology
7:52 cement textures/fabrics
5:51 sedimentary diagenesis vs metamorphism
7:52 cement textures/fabrics
8:33 recrystallization textures/fabrics
10:46 replacement textures/fabrics
15:09 fractures & vein fillings
17:00 oolites vs pisolites vs peloids vs spherulites
19:50 biogenic materials
20:55 related videos & references

Hey there, Earth enthusiast! Check my favorite Earth-friendly products:
Bamboo toilet paper: [ Ссылка ]
Bamboo paper towels: [ Ссылка ]
Compostable tableware: [ Ссылка ]
Compostable trash bags: [ Ссылка ]
Bamboo cutlery + straw! : [ Ссылка ]
Eco-Friendly Tote (great for grocery shopping!): [ Ссылка ]
Reusable straws + cleaning brushes (my fav!): [ Ссылка ]
Eco-friendly laundry detergent: [ Ссылка ]

Directly offset your carbon footprint with Wren: [ Ссылка ]
(Just click link, press get started, take the free C footprint quiz, then choose how much you want to reduce your footprint by donating to the C sequestration projects they're funding!)

Non-textbook books I recommend:
Oxygen by D. Canfield: [ Ссылка ]
Brief history of Earth by A. Knoll: [ Ссылка ]
Life on young planet by A. Knoll: [ Ссылка ]
Some assembly required by N. Shubin: [ Ссылка ]
Your inner fish by N. Shubin: [ Ссылка ]
Oxygen by N. Lane: [ Ссылка ]
Alien Oceans by K. Hand: [ Ссылка ]
Life's Engines: [ Ссылка ]

Tools I use as a geologist/teacher/student:
Geology field notebook: [ Ссылка ]
Geology rock hammer: [ Ссылка ]
Geological compass: [ Ссылка ]
Geological hand lens: [ Ссылка ]
Camera: [ Ссылка ]
Carbon-neutral pencil bag: [ Ссылка ]
Carbon-neutral backpack: [ Ссылка ]

Disclaimer: Links included in this description might be affiliate links. If you purchase a product or service with the links that I provide I may receive a small commission, but there is no additional charge to you! Thank you for supporting my channel so I can continue to provide you with free content each week! And as always, let me know your topic suggestions in the comments down below!

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