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The videos for me were very interesting. It was a mix of reviewing the basic concepts and ideas we learned in class and previous lectures, and finding out new things that I didn’t know. For example, I always thought that any plate boundary would be hot because of the activity itself characteristic of every boundary. But in the “Plate Tectonics Basics” video is mentioned how the crust could be hot or cold in a convergent plate boundary.  It didn’t make sense to me that the crust could be cold considering there is melting happening in this type of boundary. But I understood later that it does make sense since this melting is occurring several meters down while is subducting under the other plate, and is cold on top since the crust would be several kilometers away from the hot divergent boundary/oceanic ridge it formed in the first place.

Now, is the second video “Plate Tectonics Global Impacts” that mentioned hot spots and it remembered me about a daily doubt I have with the subject. The most common example to explain hot spots is Hawaii and the chain of volcanoes present. I always wondered, when the volcanoes move away from the hot spot, do they stop having magma right away? Can they still cause strong eruptions? Or eruptions at all? What’s the process exactly of becoming an inactive volcano?

I was also wondering if there is some sort of model to predict when the next supercontinent will form and what it may look like. I do not think there is a specific equation for it, but after a quick google search I found that geologists have hypothesized what the next supercontinent may look. To answer your first question, there were other supercontinents before Pangea and there will be more to come.

these videos shared some thoughtful knowledge about the place we are living in. However, if we are assuming that there were more than just one super-continent, why is Pangea the mainstream.

In the videos we learnt that there are four different layers of Oceanic Crust: Pillow Basalts, Sheeted Basalt Dikes, Gabbro, and Sediments. Are there layers that can be identified in continental crust? Which of them are the same? The only one I can think of is the Sediments layer.

I found it super interesting to learn about pangea and how our continent’s placement came to be. My favorite part of the video when they showed the triple junction where three different seafloor spreading centers come together and showed actual pictures where you can see the new rift zone appearing. It was mentioned that about 45 million years ago India collided into asia in a continent continent collision and is continuing to do so, and that made me wonder if it would ever stop? Also in millions of years from now, will the placement of the continents be completely different from how we see them now?

Something that I found interesting from the second video was that there was that there is a diverging spreading center on both the Northwest coast and in the Gulf of California in Mexico. From the simulation they played on the video, it looked as if land was moving in from the South-Southeast to make the west coast of America longer.  I know that plates move very slowly, at speeds of millimetres per seconds, so it would take thousands of years before it would be a noticeable difference, but does this imply that in some thousands of years later the west coast would have moved a sizable distance even further to the west?

The EQ happen cluster along plate boundaries. The depth and intensity aren’t really related.