Classification of Clastic Sedimentary Rocks Based on Grain Size / Sed Strat #2 | GEO GIRL

Learn how to classify sedimentary rocks based on grain size! This video covers grain size classes of sediment and detrital rocks and the affect transport and diagenesis can have on grain size, porosity, and permeability of sedimentary rocks.
Just like in igneous petrology, sedimentary textures are smaller scale than sedimentary structures. But textures in sedimentary rocks are a bit different than textures in igneous rocks, especially when considering clastic or detrital sedimentary rocks. Common sedimentary textures include hydrodynamic textures, diagenetic textures, biogenic textures, and colloform textures. Clastic sedimentary rocks are classified by grain size. Grain size classes of sediment include gravel, sand, silt, and clay or mud, which each have individual classes of grain size and specific grain size diameters. Clastic rocks can then be classified using these grain size definitions: a rock containing mostly gravel is conglomerate or breccia, a rock containing mostly sand is sandstone, a rock containing mostly silt is siltstone, a rock containing mostly clay is claystone or shale. However, sedimentary rocks can contain more than 1 grain size, so we have to use a binary naming system for those (for example, sandy siltstone or silty sandstone). But what does this grain size identification get us? Grain size of sedimentary rocks can tell us about the depositional environment in which the rock was deposited and formed, as well as the transport mechanisms that led to its deposition. We can also gain information about the diagenesis of the rock by looking at grain sizes, porosity, permeability, and cement in the sedimentary rock. This becomes very important when we are looking for oil and gas reservoirs as diagenesis heavily affects porosity and permeability of sedimentary rocks and therefore their ability to store and transport fluid.

References: Sedimentary Rocks by Pettijohn: https://amzn.to/3tnWuVu
Sedimentology and Stratigraphy by Boggs: https://amzn.to/31VIG9x

GEO GIRL Website: https://www.geogirlscience.com/ (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
0:46 sedimentary textures vs structures
1:58 common sedimentary textures
4:00 grain sizes & limits
7:55 rock types based on grain size
8:52 how to name rocks with more than 1 grain size
10:28 grain sizes in rocks tell us about depositional environment?
12:32 grain size reduction during transport
15:44 transport mechanisms that abrade grains
16:28 diagenesis also affects grain size
17:04 related videos you may find helpful
18:59 upcoming videos & references

Hey there, Earth enthusiast! Check my favorite Earth-friendly products:
Bamboo toilet paper: https://shrsl.com/3cvku
Bamboo paper towels: https://shrsl.com/3cvkw
Compostable tableware: https://shrsl.com/3cvkz
Compostable trash bags: https://shrsl.com/3cvl0
Bamboo cutlery + straw! : https://shrsl.com/3cwfl
Eco-Friendly Tote (great for grocery shopping!): https://shrsl.com/3cwfp
Reusable straws + cleaning brushes (my fav!): https://shrsl.com/3cwft
Eco-friendly laundry detergent: https://shrsl.com/3cwgo

Directly offset your carbon footprint with Wren: https://shrsl.com/3d0t2
(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: https://amzn.to/3gffbCL
Brief history of Earth by A. Knoll: https://amzn.to/3w3hC1I
Life on young planet by A. Knoll: https://amzn.to/2RBMpny
Some assembly required by N. Shubin: https://amzn.to/3w1Ezm2
Your inner fish by N. Shubin: https://amzn.to/3cpw3Wb
Oxygen by N. Lane: https://amzn.to/3z4FgwZ
Alien Oceans by K. Hand: https://amzn.to/3clMx1l
Life's Engines: https://amzn.to/3w1Nhke

Tools I use as a geologist/teacher/student:
Geology field notebook: https://amzn.to/3lb6dJf
Geology rock hammer: https://amzn.to/3DZw8MA
Geological compass: https://amzn.to/3hfbdLu
Geological hand lens: https://amzn.to/3jXysM5
Camera: https://amzn.to/3l6fGRT
Carbon-neutral pencil bag: https://shrsl.com/3cvjv
Carbon-neutral backpack: https://shrsl.com/3cvkc

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!

• #science_technology
• #geology
• #geology_crash_course
• #earth_science