Please LIKE and SUBSCRIBE. I also appreciate your continual support of these geology education videos. To do so, click on the "Thanks" button just above (right of Download button) or by going here: www.paypal.com/donate/?hosted_button_id=EWUSLG3GBS5W8 Or: www.buymeacoffee.com/shawnwillsey
Great videos. I live on the Scotland/England border very near the Iapetus Suture. We are lucky enough to have all rock types within easy travelling distance.
Really covered this rather complex subject very well professor and all in less than 30 minutes. Got an ever growing rock collection with some fine examples of metamorphics not found anywhere near me here in Illinios.
Thank you! Always something to learn in your series. It's amazing to me how much more I understand about geology, and increased enjoyment and appreciation of my observations of rocks and minerals. Love thinking about the processes involved in their formation. I have watched almost all of your productions.
These classes are definitely helping...I got all but one of the questions (missed the last one). As always, your presentations are easy to follow and retain, even for us seniors!😊
I got the question correct, although it's been since 1975 till 1979 with my last geology lessons. Your videos are great refreshers and I do learn more with each one. Metomorphic rocks are my most favorites. I've sat in on lectures on extreme mantle pressures and their effect on minerals.
Well done and interesting professor. I remember constructing, via calculations, the thermodynamic stability diagrams that would show what minerals are stable through ranges of temperature, pressure, concentration, and time. It was very interesting to learn, but wow the mathematics was time consuming and difficult! Now there are likely computer programs that will generate this information at a tiny fraction of the time. We did it with pencil, paper, calculator, and the JANAF tables. Great memories of lots of work and little sleep!
I'm watching this while I take a break from cutting rocks from Mt. Apatite in Auburn, ME. It's a historical quarry site, where the gems for the Josephine Peary Necklace were mined. Lots of gneiss! You would find many great examples in my buckets of slabs!
Very interesting and informative. I had to run out to my yard to look at the rocks I used from nearby mountains here in western Arizona, to line the driveway and found some of the very rocks you profiled. gniess , schist , quartzite and found at the upper most elevations some yellowish granite that I think is very old , maybe 1.7 billion years , precambrian .
Excellent, love these videos. I live in the north east of Spain I assume that in my area there are lots of Igneous rocks but in them there are what I assume to be Intrusions going through the rocks. It would be great if you could talk about the types of intrusions time permitting. As always thank you for your very interesting video's
A dense and very educational episode, thank you Shawn! I really enjoyed watching it after my work day. But isn't it #16 rather than #15...? Oh, and I answered all 4 questions correctly so I'd say your teaching really works :)
Another solid geology video/lecture from Shawn Willsey. Thank you! However... I wish that I could find the classic comedy sketch which involves a multiple-choice question where the offered choices are something along the lines of: a) B b) C c) E d) A e) C The second of the end-of-episode quiz questions reminded me *very* strongly of that sketch. We are "lucky" that the 2nd and 3rd choices have the option matches the "Unit" letter! If you ever have a similar quiz question (in a video or in class), please try to avoid options where the option's text involves a single letter.
I live in Wales and my roof, and most of the others around here, is tiled in slate. In fact, it's so abundant in the north of the country that slate was often used in fences too - slivers driven into the ground and held in alignment up top with twine or wire.
@@shawnwillsey Aye, that's slate country up north. I'm down south in anthracite country. As a youth I witnessed the end of mining, thanks to Thatcher's reign of devastation
Thanks Shawn, really helped my understanding. Interesting that the gneiss parent can be on different ends of the spectrum, shale/granite. Can radioactive rocks, when present, contribute as a heating source for metamorphism?
The gneiss parent makes a fair bit of sense when you consider what shale is made of: mud. Which is just fine-grained weathered particles of ultimately granite (etc.). If the temps and pressures are high enough to fuse everything together and recrystallize the material, well, ultimately the underlying composition is similar! In that line, I expect sandstones to end up the same way under high-grade metamorphism. For radioactivity, indirectly all so in the sense that radioactivity maintains Earth's underlying temperatures, but you probably mean directly. Directly, rarely so, since radioactive elements tend not to concentrate to that degree. For notable exceptions, look up 'natural nuclear reactors' - where, mostly uranium, happened to concentrate enough by natural processes to start chain-reacting and releasing significant amounts of heat. Iirc, none are known to be currently operational, but there's clear evidence in a few locations of this happening previously (before 'burning' through too much of the fuel to remain critical)
Hi Shawn - is there anyone doing any geology to explain the flooding events in the mountains due to Helene? That would be very interesting especially if there was some focus on whether there were things that could be done to prepare or divert the water and slides. A co-lab with you would be super-awesome to get max visibility cheers!
It is probably worth noting that one of the hallmarks of subduction zones is low temperature high pressure metamorphism i.e. the minerals found in ophiolites sections of a subducted slab which subsequently detached and were brought up to the surface, this involves some interesting exotic stuff such as jadite for example which requires deep burial but low temperatures followed by some process bringing the rocks back to the surface. Now one question I'm curious about the answer to is how do you handle the classification of the unmelted section of rocks which have had minerals removed by partial melting? For example the rocks left behind after the fluidization of low melting point minerals like quartz, or perhaps even some of those rocks which got hot enough for quartz to begin to separate out and flow into bands within the rock. Is the rock still igneous even though the material in question is the part that never melted or would it be contact metamorphism or similar? Where I live in the piedmont the bedrock is all medium grade metamorphic rocks particularly muscovite schist from the basement of the Appalachians though there are some nearby areas with granitic rocks mixed in there it is otherwise basically all metamorphic well up until you hit the sedimentary Newark group from the failed rifts associated with the opening of the Atlantic but those are a regional outlier.
Under the alps or hymalayas, one problem they encounter when digging rail tunnels is heat. Does the pressure of all the rock above the base end up creating pressure and head that would be enough to make metamorphic rocks? Or is the pressure needed in a scale achievable only by continental drift and mountains don't even come close? Taiwan has a lot of marble. What would have created it?
In a previous lecture, you mentioned Rodinia, and your map had Laurentia. When they told us the Laurentian mountains north of Montréal were the oldest, i had no idea that the whole canadian shield comes from the original continent and this much older than "just very old". What caused Rodinia and Gondwana to move from near the south pole past the equator and mostly northern hemisphere? Is it correct to state that the Earth's diameter is larger at equator because of its rotation and that its rotation would have attracted parts of Rodinia to move north towards equator? what would have cause them to not stop at equator and continue to move north? Or would it be magma movement at the planet's core that moves a certain way and infuences how land above it is pushed? (And to think Québec was once a tropical place !!!)
On your last quiz question, does presence of ignious rocks strictly guarantee presente of magma at one point? Would there not be many cases where igneous rocks were pushed up well after they were solifidied? You mentioned that if I tried to make them at home on my oven, it would take a very long time. I can understand metamorphic rocks forming around the Kilauea reservoir. But would a short burp of lava that lasts a day or two as happened a few weeks ago remain hot enough to create metamorphic rocks under the freshly ejected lava ?
How are the rocks described that result from high energy explosions, eg. those around old nuclear test sites? It sometimes appears that the rocks are truly melted.
Good morning, please answer me one thing: Looking at the supposed images of Mars via NASA, we see a lot of red/yellowish rocks and we know that it is iron oxide that gives this color, but how can there be iron oxide on a planet that has no oxygen? , where oxidation does not exist without oxygen?
