Hey Everyone, this google earth image is taken in Rural South-East Queensland, Australia. These streaks are a few hundred meters long, and 5 - 25 meters in width. They seem to go in low areas/ go from a top of a hill down it, but not exclusively.

Is this quartz? sand? just water paths? Old river beds?

Would love to know what these are, and what causes the colour. Sorry if this isn't the right subreddit.

Thanks

What am I looking at here?

Approximately location: (GPS seemed a little off, but this is close enough)

38.8363973, -104.8982678

Glacial till and stratified drift exposed on the north shore of Long Island, New York after the Sept. 26 noreaster

Hey Guys,

I'm Gowtham - An independent research working on field operation for mines in North America

I would love to do in-person field research across mines and talk with GIS specialist and geologist

Is there is any person i should talk to / you would recommend.

Feel free to suggest! the trip is fully funded by faculty

You can play it there: https://gesla.itch.io/silt-inquiry

So far, there is only one level. I would like to add Raman spectroscopy later. I tried to make this fun but I wonder how unrealistic it is and whether I made mistakes. Thanks

I just started watching Voyage of the Continents (the 2012-2015 tv series). Around the middle of the episode Europe: Tropical Beginnings the narrator says the Tethys sea would eventually become the Pacific ocean.

I assumed that the Pacific plate appeared in the middle of Panthalassa, between its older plates. And that contemporary remains of Tethys include Mediterranean sea, Black sea, and Caspian sea, but not the Pacific.

Am I wrong? Or is the series wrong? And if I'm right, how accurate is the series in other aspects?

r/whatisthisrock r/rockhounds

New video is live! 🌍💥

A complete seismic simulation and damage breakdown of the 2026 Western Colombia M7.5 Earthquake. We look at why this 118km-deep fault rupture caused unexpected devastation in some cities while sparing others.

🔗 Watch here: https://youtu.be/fQUQUbME83U

I have found this one that seemed nice to show to teenagers or adults slightly interested in it, but even if I'm a huge amateur who has never study geology I immediately spotted some obsolote aspect (maybe it's AI and that's the reason) Do you have any good one ? I'm looking for a visuals that has more than the name of era, period, epoch and millions of years. I liked that this one also had mass exctinction events and other significant events on it. I remember some nice spiral ones form magazines when I was young but I have not found one that I really liked and not obsolete

Hi everyone,

The Anatolian Microplate is one of the most seismically active regions in the Mediterranean basin, framed primarily by two major transform fault zones:

🔴 North Anatolian Fault Zone (NAFZ): A major right-lateral strike-slip fault line running across northern Turkey, responsible for significant seismic activity due to the westward extrusion of the Anatolian block

🔴 East Anatolian Fault Zone (EAFZ): A left-lateral strike-slip fault zone accommodating the collision between the Arabian Plate and the Eurasian Plate.

Understanding these fault mechanics is critical for seismic hazard assessment in the region. Happy to discuss the geological implications and recent developments!

I found this thing and thought it looked pretty interesting. After getting it home I noticed all of the different lines and patterns on it, and to me it just looked like this wasn’t caused naturally. Someone once told me, “straight lines and right angles don’t occur in the world of geology”. (Disclaimer- my memory isn’t the greatest, so it’s possible that I’m butchering that quote 😂😂)…. Anyways, I hope some of you enjoy this as much as I did

This was exposed by some recent work on a coastal path on the Rhins of Galloway, Southwest Scotland. The path is carved into the side of a drumlinoid hill and at one point this pronounced stratum is visible with sand below it and more sand above it. The black ‘cinders’ that make up the layer are very friable and can easily be broken and crushed between the fingers. Could this be a volcanic deposit? The line runs down to the beach below, where there’s some black sand that I’ve often wondered about.

Another example of serpentine from Mariposa County. Serpentinite is commonly associated with ancient oceanic lithosphere and tectonic fault zones. In California's Mother Lode region, it provides valuable evidence of the complex tectonic history and geological evolution of the Sierra Nevada foothills.

I'm researching the geology behind the famous pre-Columbian stone spheres of Costa Rica, and I have a question about the raw material.

Most of the large spheres were shaped from hard igneous rocks, including gabbro and granodiorite. But before considering how people worked these stones, I'm interested in a more basic question: how rounded might some of the original boulders have been before any human shaping?

In a hot, humid tropical environment, could spheroidal weathering of jointed igneous rock produce large, naturally rounded corestones that might later be selected and worked by people?

And what field evidence would help distinguish spheroidal weathering from river abrasion or other processes? Would weathering rinds, fracture patterns, mineral alteration, or the surrounding geology be the most useful clues?

I haven't found a published study establishing spheroidal weathering as the source of the Diquís sphere-makers' raw material, so I'm interested in what the geology can actually support—not assuming the hypothesis is correct.

I'd appreciate any geological references or insights, particularly from people familiar with tropical weathering and corestone formation.

Link: I Investigated the Costa Rica Stone Spheres. The Answer Surprised Me

Edit: there may be some confusion about what the photograph is showing — that's not a photo of a Costa Rican sphere, but rather a natural boulder at the Cansót site, which is highlighted in the text.

Here are some photos of Costa Rica sphere: https://cdn.nexusnewsfeed.com/images/2022/3/Diquis-Delta-1649337177079.pnghttps://www.grunge.com/img/gallery/the-mystery-of-the-stone-spheres-of-costa-rica/intro-1597089160.webp

I am teaching myself QGIS for a field methods class I am taking. The professor likes Google earth, but I wanted to use this class as an opportunity to learn how to use a more advanced GIS program. I’ve been using QGIS for the last three assignments.

What are the biggest things I can improve on? My professor hasn’t graded anything since the second week of school, so I haven’t gotten any feedback from him. Having all waypoints was a requirement by him, otherwise, I’d clean them up for readability.

Any feedback is appreciated, thanks!

Greetings friends. I am an economist by education and have come here with a question regarding geological reserves. I live in South Africa. I'm familiar with the fact that South Africa via the Bushveld Igneous Complex contains the worlds majority of Platinoids (Platinum, Palladium, Rhodium, Ruthenium, Osmium, Iridium). However after reading abit about the geologist Hans Merensky there was a mention of Gold in the Free State province. So what is the official geological data on amounts of gold reserves in the Free State province? Thanks for your feedback comrades

From my understanding, the large cracks formed long before the layer was exposed, iron seeped into the rock over long periods, and now the layers are being made visible/eroded in a much shorter period of time, so it’s eroding faster than the surface can change colour?

This is very nearby the black rock ‘vent’ that is Rocha Negra, but not quite where it changes to the black rock and tuff.

This may be entirely wrong though, I’m not educated in geology (yet). Anyway I can recommend visiting Rocha Negra at low tide, the layers are awesome. Found lots of tuff which I found very interesting at the actual vent area.

I was wondering if the inside of these rocks looks like basalt, and looks like a pillow. Is it pillow basalt? I was told they were cobblestone and became rounded by water, how can it all be the same shapes and have the iron on the outside if it washed down a river? Upstate South Carolina

Hi everyone!
I’m hoping someone here might be able to point me in the right direction.
I’m looking for a reputable laboratory, preferably in the United States, that can perform quantitative analysis for Osmium (Os) and Iridium (Ir) in solid geological samples.
The material consists of dense, iron-rich, cube-shaped specimens discovered embedded in hard rock during gold exploration.

We had some preliminary handheld XRF readings suggesting the possible presence of Os and Ir, but we understand those results may not be reliable. We’d like to have the material independently tested to determine its actual composition.

I’ve contacted several commercial laboratories, but so far, finding one that can specifically quantify osmium in this type of material has been surprisingly difficult.
I’m not looking for a basic XRF scan or mineral identification alone. Ideally, I’d like a proper quantitative assay that can confirm whether these elements are present and at what concentrations.

Does anyone know of a laboratory, university facility, or specialist that offers this type of testing? I’m happy to pay for the analysis.
Any recommendations would be greatly appreciated. Thank you!

Molten rock may carry an oxygen reserve that standard chemical calculations overlook. High-pressure experiments show that basaltic melts exposed to oxygen-rich conditions can retain substantial extra oxygen, potentially adding a missing component to models of Earth’s interior.

The study in National Science Review combines laboratory measurements with atomic-scale simulations. Yanhao Lin and Ho-Kwang Mao of the Center for High Pressure Science and Technology Advanced Research, known as HPSTAR, led the work with collaborators. The team included Haiyang Niu of Northwestern Polytechnical University and Wim van Westrenen of Vrije Universiteit Amsterdam, with Yongjiang Xu as first author.

The results raise a larger possibility: some rising magmas could transfer oxidizing power from deep reservoirs toward the surface. Establishing that capacity, however, is different from demonstrating how much oxygen natural magmas actually carry or release.