This is where the videos for the University of Toronto's online field course will be posted. These will include videos for different sites for online filed trips and instructions for different field methods that will be covered in the course, including taking strike and dips, using a stero net, and sketching out crops on a geologic map.
I’ve found some in southwest Michigan that look like those, but more like a tektite.. Melted and glassy on the outside, but still basalt like inside.. Very weird assortment of clasts, and what looks like copper sprayed all over inside, but very small blebs for the most part.. They do not make sense to me at all!!
Thank you!!! I’ve been racking my brain thinking about why my rocks look so weird!! Southern Michigan has so many of these same rocks as the Sudbury complex.. but mine honestly look older or something…
No, augens are porphyroblasts that are then sheared to form lenticular structures. This metaconglomerate is a clastic rock that was then deformed stretching out the clasts that made up the original rock.
Enjoyed your geologic enlightenment. I collect World coins, Peru, Bolivia etc. invest in silver miners too. Petosi is the source of many old silver coins 1650 to 1850 or so. PTS monogram is the city’s mint mark. It was the Wild West of the old World and its pile of silver fueled our world today.
...makes one wonder at the amount of earth being moved to extract all these ores. Gotta move and process tons and tons of earth to extract the tiny amount of "good" stuff. All that production cost, plus a healthy profit for the companies that do it, ALL of it comes from those little bits and flecks of "good" stuff we see in those samples. Imagine the ratio of element vs "waste".
A copper deposit, if near the surface can be profitable with as little as 1.5% to 3% per ton of ore. If of course you can extract to ore body from the surface with open pit methods. A rich Copper/Gold vein deposit needs to be at least 1-2 ounces of Gold per ton when worked in the more traditional tunnel & adit/stope method.
Yah I looked it up but couldn't find too many details other than its there. Unfortunately it seems to be on private land so would be a bit tough to get to to take a look.
Coal is laid-down by past vegetation - layer upon layer over thousands of years , then compressed. Nothing extra-terrestrial in Chelmsford. The only thing that was ever extra-terrestrial in Chelmsford, was when I cycled from London up to Harwich, to catch the ferry to Holland, this back in June 1988...
True, but that isn't the case here, the Grenville orogeny is quite well documented to the south and created what would have been one of the highest mountain ranges on Earth, though its been planed flat at this point.
You might be able to find a few microdiamonds but economic diamonds come from kimberlite or lamproite intrusions that formed at extremely high pressures deep in the Earth. Uranium could form in the sediments that fill impact craters but these form more due to interfaces between oxygenated and reduces fluids and wouldn't really be related to an impact.
Sorry it took a while, I just added some for pyrrhotite and pentlandite, will try and do one showing the differences between gold, chalcopyrite and pyrite soon.
