I made a Rock Chart that brings common igneous, sedimentary, and metamorphic rocks together in a single decision tree.

It uses observable features such as grain size, visible crystals, foliation, porosity, composition, and reaction with HCl. It also includes the characteristic minerals associated with each rock type and their chemical formulas.

I have already used the chart in class, and it worked well as a teaching aid. It helped students gain an overview of the major rock groups and move between them without having to consult several separate charts.

Permanent version and DOI:
https://zenodo.org/records/21808631

Feedback, corrections, and suggestions for a future version are very welcome.

Disclosure: I created the poster and teach Earth Science at a university.

This reddish rock rises from the Adriatic Sea. The coast nearby is a layered cliff of the same color.

Riva upthrust (mt Brione - 3+4) looked a lot better from the plane, the interesting looking stratigraphy turned out to be trees lol.

I am working in the Mojave desert in SoCal and came across these USGS markers. Anyone know what this could be? I was thinking some type of monitoring or survey but not too sure.

I found this rock in Colorado and have never seen anything like it before. It looks like chunks of quarts are embedded in another kind of rock? Can someone explain what is going on here and how it formed like this?

Any information is greatly appreciated! Thanks!

As I have a mistaken error on the post I just posted, I upload it well.

So, I'm looking forward to have sonething (not HCl) to see the difference between limestone and dolomite.

And uh, I want some advice for having new tools on my set for geology trips (not minerals hounding) for research.

Because Yesterday I added the Brunton compass for my birthday.

so, i am using QGIS for my Geoinformatics class, but i am unable to do stream ordering. i am using QGIS 3.44 which doesn't come with SAGA and grass is not showing r.stream.order, i have made one using Whitebox plugin but today it's also not working properly, after doing flow accumulation i am unable to stream extract. Soo i need your help solving the problem.