In my town we got beautiful curbs of different types. Im assuming gneiss and granite but not sure. My favorite is the first stone, looks like a piece of art.

Note: the lines on the rocks don’t all go in the same direction. Some vertical and other horizontal

Maybe a different way of phrasing it with different geographical context, why did the Yellowstone hotspot transition from the basalt that made Siletzia and the Columbia River basalts into the rhyolite that made the more recent calderas? Does only 10ish km of continental crust make that much of a difference or was it something else to do? I read that there’s not much intermediate rock like andesite?

Hey yall. I am wondering if anyone has any monocle or eyeglasses magnification lens recs for field work. Due to eye problems, my eyes have a hard time refocusing after using a hand-lens and would like to reduce the stress on my eyes when refocusing. I understand that hand-lens are sturdy and great for fieldwork however I would like something that I could use both eyes for mineral identification. I have been trying to look at different things like jewelers glasses but have not found anything that would do what I am looking for.

Hand-lens that are glasses friendly are also welcome as well.

Okay these first materials are from our land. As near as I can tell, we are terrace deposit or Tokio formation. I'm southeast of Idabel and our house literally over looks the coastal plain. Forgive me for not posting the exact location. All my clays are sandy. These where processed to remove most of the sand before testing.

This is a light colored clay. It's a pain to access as it's at the bottom of a creek with steep banks. Right next to it is a spring that has never stopped running even during really dry years. In the creek I find lots of quartzite. I've found a few agates and some conglomerates. I found what I think was white serpentine in this light colored clay (white, very sparkly). These pipe (?) structures are upstream from the clay layer. The red is hard sandstone and the white is more of the white clay. The creek also has lots of white sandstone (?). The sandstone contains very little clay but can be broken apart pretty easy. The clay fires above cone 6 (about 1200C)

This next one is the white sand I removed from the light colored clay. There are other locations that contain just the white sand without the clay.

This one is a an extremely fine sand. This comes from an odd low spot on top of a hill that holds water when it's wet. It's got alot of organics in it from the water and the trees so I processes it and pour off what little clay and the coarser sand particles. I get some sandstone and iron concretions out of it. This stuff is powder fine. Makes an awesome glaze ingredient that I don't have to grind.

This is the main local clay that I use. It's in a higher layer than the light colored clay. This particular batch of clay, I removed all the sand and it fired with less than 1% absorption at cone 6. Sounds perfect until you realize it has a 15% drying shrinkage. So I leave most of the fine sand and mix it with feldspar and kaolin. It's acidic and their does seem to be significant differences in firing temperatures depending on where I dig it, but how much sand I remove affects that as well.

I call this one Sugar Creek clay but I think it maybe Walnut clay? Found under layer of what I believe to be Goodland limestone. Location is 33.92747055603416, -94.53065741860809. Plastic vitrified at cone 02. It had pieces of limestone in it and I sieved it down to 100 microns. I use it as a glaze ingredient now. I think I roasted this at 1000F before the analysis but don't remember for sure.

This material is from a local limestone quarry above the limestone and hard pan layers. I believe it to be Kiamichi Shale. Location 33.93060978243283, -94.77100598594791. It looks like shale and at first wouldn't break down in water but I dried it in my oven and then it broke down and was plastic enough to form test bars. I also use limestone from this quarry as a substitute for whiting.

And last but not least, this is a marl from Southwest Arkansas. Location is 33.680160646301445, -94.44293602420451. I was hoping it was chalk when I dug it but it was actually plastic enough you could roll a coil and wrap it around your finger. If you check the location on google maps, you can see the cement plant just down the road and where they mine the marl/chalk for cement.

This glaze is 49.5% local materials.

I'm a potter who enjoys working with local materials and have made some effort to identify formations. I've had whole rock analysis done on quite a few local materials. If anyone is interested I can share those with the geology information I have.

EDIT: I made a post with the analysis and pictures https://www.reddit.com/r/geology/comments/1x60nnt/chemical_whole_rock_analysis_of_some_materials/

Found a rock with a slight crack, broke it and found this :)

I put together a 12-minute reconstruction of Sunday's flash flood on the Budhi Gandaki in Gorkha, Nepal. It's the second major Himalayan flood in seven weeks, by ICIMOD's count. What it covers:

- The gauge record: at Arughat (DHM station 3572) the river rose about 5 m in 30 minutes, with no rainfall, before the gauge went silent at 08:40.

- The seismic signal: a 4:22 am signal on the KKN station, flagged by Kristen Cook on the day.

- The source area: the Syar Khola below Chamar, compared in Sentinel-2 images from 1, 6 and 11 Oct.

- Precedent: Rasuwa, Birendra Tal (2024) and Chamoli (2021, Shugar et al., Science).

- The official finding, which landed after the film was made. NDRRMA's preliminary assessment says an ice-rock avalanche at about 4:20 am triggered a landslide whose debris repeatedly blocked the Syar Khola, backing water up about 1.5 km. ICIMOD says satellites confirm an ice-rock avalanche and glacier collapse. The film calls the cause unconfirmed, so read those sections with that in mind; the update is in the description.

I deliberately didn't model a dam height, lake volume or breach hydrograph, because no agency has published one. The flood front and the dam cutaway are illustrative; the terrain (Copernicus GLO-30) and the gauge levels are real.

A question for people who know Himalayan mass flows: with repeated blockage and partial breaches rather than one dam failure, would you expect a single 5 m pulse like the Arughat trace, or several smaller ones that merge downstream?

https://www.youtube.com/watch?v=gVxF-vGrw1g

I was looking for one for Maine so I could see why types of rocks were along particular coastal areas. It seems everything has been pushed into the National Map format, and I have to download individual maps. This is frustrating when I want to view an area as a whole.

Source of the pictures here and here

The valley Middlesboro, Kentucky sits in is a meteorite crater about 6 km across. USGS geologists identified it in 1962, and in 1966 Robert Dietz found shatter cones in the sandstone, which only form in impacts.

Around 1886 Alexander Arthur, a Scottish-born engineer in Knoxville, got interested in the iron deposits near Cumberland Gap and planned a "Pittsburgh of the South". The city was incorporated in 1890, but the ore was poor and the Panic of 1893 ended Arthur's development.

This is my own render of the bare-earth lidar. The flat ground across the middle is the crater floor, with ridges around it.

1. Bare-earth lidar: flat crater floor with ridges around it
2. Recent air photo of the same area

Numbered pins on picture 1:
Pin 1: Flat crater floor under the town streets
Pin 2: A wide curving man-made channel

Lidar: USGS 3D Elevation Program (3DEP), public domain.
Imagery: Kentucky DGI - KyFromAbove, 2012-2024, CC0 1.0.

I have a weird question but i study geology and went to a holiday in Sicily. I got some rock from mount Etna that are around 5-10 cm and didn’t think about airport security. I have a carry on so they will definitely see that i have rocks in my bag. Will this be a problem?

They are not high order interference colors but I could be wrong, I’ve never looked at these under thin section and was curious if anyone knew if these were. They are pretty large 0.3mm and are in a mudstone. Supposedly there are supposed to be apatite, zircon, monazite, and other REE bearing crystals. Was hoping someone could help me identify them!

I found these specimens in Sierra del Morrión (Aldama, Chihuahua, Mexico). Fine-grained grey matrix with brown-ochre material standing out in relief; some parts look like tubes, others are flaky and irregular. One piece shows an oval section with a dark center.

The area is mostly Cretaceous marine limestone, so my hypothesis is marine burrows (maybe Thalassinoides-type) with an iron-oxide-stained infill. But I'm not ruling out pseudofossils like iron-oxide crusts or concretions. I haven't done the HCl test yet.

I'm a geology student and still learning, so any corrections are welcome. Thanks!

Here, idk how many meters up maybe 150+ recent budhigandi flood here was apparently really high because of the narrow gorge (extremely narrow). He says, rocks flew up and the trees seem baren now. Reminds me how narrow vallies can cause the flood to become much higher. Idk if this will happen downstream tho, this is way up near the landslide zone.

Missouri floods apparently got higher in narrow vallies even whem being way downstream.

Also crazy how one of the biggest 3 floods that i have ever seen in my life happened in nepal, in last 45 days 💀 Bhotekoshi was has to be the biggest ever. Budhigandi was like half its size too. Still really high upstream, ima drop a pic in comment too

An older neighbor is clearing things out, and these books are set aside to give away. If anyone is interested, please DM me your address and I’m happy to send them to you for free.

Spotted this layering and thought it looked interesting. I don't know much about the composition but its located in the hills just south of Ballater Scotland. Would the darker soil be the result of burning perhaps?

TL;DR: Combining active Arctic sea-ice pumping with a pre-rinsed, desalted macroalgae (seaweed) gel matrix to 3D-print high-tensile, multi-layered "rebar" ice that resists flexural ocean swells and summer melt.

Hello everyone, I have been running a theoretical thought experiment around mechanical sea-ice preservation and wanted to put this concept out to the community as an open-source (CC BY 4.0) proposal for peer feedback, CFD/thermal modeling, or further collaborative development.

The Core Concept: MPL-Pykrete: Current geoengineering trials—such as pumping ocean water onto winter sea ice—add thickness, but the resulting ice remains brittle under wave action. Additionally, salty brine drainage creates internal structural weakness.

By introducing a desalted seaweed fibre slurry in alternating cycles, we create a laminated composite—effectively 3D-printing bio-reinforced ice.

Structural Layering Breakdown: Layer 5 (Top): Pure Seawater Ice — White, High-Albedo Solar Protective Cap

Layer 4: Seaweed Gel-Ice Matrix — Tough Structural "Rebar" Layer

Layer 3: Pure Seawater Ice — Thermal Buffer

Layer 2: Seaweed Gel-Ice Matrix — Tough Structural "Rebar" Layer

Layer 1 (Bottom): Base Natural Sea Ice

Key Mechanics & Mitigations: Tensile "Rebar" Layering: Macerated seaweed (packed with alginic acid and cellulose) forms a flexible gel-fibre matrix. When flash-frozen, it absorbs bending and shear stress from ocean swells, preventing micro-fractures from propagating through the ice sheet. Pre-Rinsed / Desalted Biomass: Rinsing harvested macroalgae (e.g. invasive Sargassum or cultivated kelp) with rainwater or low-salinity washes before processing removes surface salts. This raises the slurry's freezing point to near 0°C and prevents brine channel formation, creating a dense, non-porous composite.

Albedo Preservation ("Dark Ice" Shielding): To prevent dark organic fibres from absorbing solar radiation during continuous polar summer light, each organic slurry layer is capped with 4–5 layers of clean, high-albedo pure ice. Citable DOI & Open-Source Status Released under Creative Commons Attribution 4.0 International (CC BY 4.0) as open-source prior art—free for anyone to model, test, or build upon. Conceiver / Author: Stuart Peacock OSF Project / DOI Link: doi.org/10.17605/OSF.IO/6UZBY

I would welcome any insights or critiques from anyone working in materials science, fluid dynamics, or polar engineering!

Hello all,

I’m looking for any online geology courses or video resources that could help me brush up on the basics again. Things like cross sections, mapping, structures, all the stuff you lose if you’re not using it.

I did an Earth Science undergrad and then a Natural Hazards MSc that leaned more into physical geography and geophysics than geological processes. I’m on a gap year now and feel like those core geology skills are slipping a bit.

I really enjoy learning about contamination, especially mining‑related stuff, and I’d love anything that could help me keep sharp and show employers I’m still building my skills.

Any advice would be massively appreciated!!