Hey guys, I wanted to make a video kind of walking you through this assignment. So you have sort of a verbal reference of what this document is all about as far as part two of our project goes. So some people tend to prefer to hear things discussed as opposed to reading it on a piece of paper. So I wanted to break it down for you so you’re comfortable when you see this document. Okay, so I start out obviously our due date for part two is going to be this coming Sunday October 29th just before midnight. You will submit it to Canvas.

A couple of administrative items I wanted to go over that stem from the great products you guys turned in from part one. I’m going to test this real quick. I want to see if I can flip between Google Earth and my document.

Okay, so in Google Earth, as you can see on my document here, I’ve actually removed the grid which within Google Earth you’re going to go to the header which you can’t see but you’re going to go view grid and see how that puts this latitude launch to grid on it. That’s a little too busy for our project. It can be a good frame of reference for you if you’re looking for location specifics about an area. You can kind of zoom in and you can see where you are. But for our project, you do not need that. So I would strongly prefer you not have the grid on when you take your screenshots. So that’s just at the top you’re going to say view grid and it will turn off pretty easy.

Secondly, a couple of specifics about your profile line. I want you to take some liberty in the colors you use so you’re more than welcome to change the color of your line. I think for the most part when you imported your lines that came in is very thin white lines. I’ll show you how you can do that in a second if you haven’t already figured it out. I recommend you also turn off the other student’s lines. They were just kind of compiled into one file for you to import. You really don’t need to access those. So for those two items within Google Earth, basically if you want to change the color of this yellow line here that I’ve drawn, you’re going to either select on it and right click, which sometimes doesn’t want to work for some reason. Okay, there it is. In on a Macbook, I’m hitting control right click and it’s under get info. You can also come to the line. If you select any line that’s in one of your layers over here, if you select on it in the map view, the place is jumps to what that is. And then you come over and with your mouse, you’re going to, I’m going to again, for Macbook, hit control right click, get info. And that brings up this dialog box that you’re getting used to. And under style and color, you can come and change the color. We can change, oh, you always do that, you change the width. And you can also decrease the opacity, which means you can make it more or less transparent. What’s neat about it too is it will give you the measurements, the length of the line if you want. If you had a polygon, it would give you the dimensions of that polygon as well and I’ll show you that in a second. And then you say, okay, and you see I’ve changed my yellow line into an orange line. I’m going to change it back to yellow because that’s what I want.

Okay.

And then the other item I was going to say is to remove your classmates lines so you can individually select these lines. Right, so let’s go here. You can see somebody’s line right there. This is this, this trending line. That’s that one. And what’s this one? So if you have this South North Galapagos line, you’re going to want to turn off this Coco’s Panama Columbia. Because it’s just disruptive to your view. Anyway, so I would suggest you just turn them all off except for your line. You really have no need to have those active.

Okay.

So along the same lines, you can deselect any unnecessary items that you have in Google Earth from your places. I’m going to actually capital places.

By that, I mean, sorry, within Google Earth, you’re going to come within your places. And like, for example, we have, I’ve got obviously a bunch of stuff. But we did.

There’s our circles. I think I have those.

Well, so let’s say your seismograph locations. Remember these guys. Let’s fly over there real quick. So if you’re a line. Excuse me. It’s over here in Japan area, which pardon me. I know somebody has. You will want to turn off these. So they’re not present. Right. To that effect, these labels right here, like Okinawa are under borders. And I thought it was.

That’s borders and labels.

Oh, these are my plate names. Sorry. If those are two obtuse of the plate names. If they’re in the middle of something, you can come in here to the plate boundary model. And either turn them off.

Or turn off individual ones. So it’s good on Okinawa, whatever that is. Or not enough bit of quarter for some reason. You can just turn off that one. So the idea is to make a very clear, uncluttered map presentation.

All right. Now we want to make sure we orient all your maps north before you make your screenshots.

I discussed this down here.

Basically, in map view, as you’ve probably noticed, I’m going to go back to my Antarctica line.

Just to make it cohesive.

Hmm. Just fly there.

All right. So here’s Antarctica. And it is not oriented north. If you see this, we’ll move this over. North is now headed this direction down to the bottom right. Let’s say, you know, four o ‘clock. All you’ve got to do is double click on in. And that will orient it north, which is you need to make sure all your maps are oriented north. Just that’s how in general maps are made.

So I discussed that in here, where I show you that here the end is pointing up. This is correct. Green check mark. Here the end is a skew slightly to the right. That’s incorrect. So I discussed that.

Okay.

Now, also along the same line, you need to make sure you’re viewing in a vertical view, otherwise known as a bird’s eye view, before you make your map. So like, if I don’t want to print a screenshot of this yellow line with this view, I need to kind of make sure that that yellow line is centered. And you’re going to come over to this arrow, which is in this one, which allow you to kind of rotate it. So you’re looking down on it. So see how this is kind of bringing it’s rotating the globe. So we’re looking straight down at Antarctica. And then you double click to go north. So that would be looking at it on a pretty good bird’s eye view, as opposed to being a skew, which would be that. So here you’re looking at it at an angle. We don’t want this. Therefore, that’s what I describe here, is make sure you’re in a bird’s eye view.

Okay. So now regarding this tectonic boundaries area or comments I’ve made, if you need help understanding what tectonic boundaries exist in your area, you were provided a layer called plate boundary model. And if you click on the heading that I have highlighted in red right here,

this will bring up a dialogue box that tells you what the legend is. So you can see, for example, in this area, this southern boundary of what’s called the Shetland Plate is considered a transform fault. Actually, it’s an oceanic, I’m sorry, it’s a continental boundary, riff boundary right here in the light green. And then the blue is a subduction zone. The red is, as it says, an oceanic spreading ridge. So all you’ve got to do is click on this and this dialogue box comes up. So that can help you. There’s no reason you should have to struggle to understand what the boundaries are. And then what you’ll do is look at them and profile view if this is your area to understand the orientation and what’s going on. Okay, now to your assignment of part two. Specifically, you’re tasked with coming up with five Earth Science based observations. So you’re just going to list them in your presentation document. And they’re going to be about your profile line. There’ll be your own observations of your base map and or your profile line. So these five statements are a starting point for ultimately your interpretation. In my grading of your part two assignment, I’ll be reviewing these five statements. So they need to be pretty unique and independent of each other. And basically just tell me what you see. You don’t have to make it high level Earth Science or high level geology or high level plate tectonics. Just state your observations. And I’m going to help you individually refine those. You can use the additional layers you provided it for help. So for example, in my area that I keep referring to down here in Antarctica, I’m going to go over here and turn on the additional layers you provided. One is the volcanoes of the world.

And you can see those pop up right here on the north end of this peninsula of Antarctica. You’re also provided an epicenter layer that shows epicenters in recent time of certain earthquakes. And then the last one was your age of the crust. And that can be a little confusing. So I’m going to turn that off for right now and then we can discuss it in a minute. But with respect to your volcanoes, you can see that the line that I’m using here to illustrate your assignment is not directly related to some volcanoes. But what I want you to do just in your sort of work to evaluate what’s happening is you’re going to create a new line and you’re going to do a cross section or a profile line perpendicular or at some angle to your existing profile line. I’m going to make it a different color so you can see it. So I’ve made that red line there. And what that’s going to do is right allow me to make another elevation profile

that Antarctica is not necessarily the best location. I’m going to extend that line actually.

Get info and extend it on it through here so you can kind of see a little bit. That looks a little more detail of what’s happening here. So here we go. And now we move the window down so you can see. All right, so I’ve got my red line that is at a high angle, almost perpendicular to my profile line, my assigned profile line. And you can see I’m going from the north end on the left down to the southern end. Now why is this all flat? Well, this is one of the reasons why nobody’s doing a profile line through Antarctica because the data Google Earth has is using satellite information and the data they use to create the Google Earth presentation doesn’t resolve what the land or the Earth’s crust is doing below the ice. It’s too thick. So that’s why it’s all flat. There are some areas and if this was your area you could kind of look and see what’s going on in these little peaks and valleys. But if you can, if you see coming from the north where under oceanic water we go through a purple boundary at the top, I’m going to go open up.

I don’t know why it’s not loading into this time of the day too. There we go.

So the perfect boundary is not showing, let’s see. Not to figure that one out, but let’s take the blue boundary. The blue boundary is a subduction zone. So if you come through here you see this that I’m going to highlight in red in my profile line is tracing right on top of that. So we know this is a subduction zone and then we come up and I can tell just so you know by the depths of the surface of these this plate and this plate that this northern plate or the left most on the profile line is subducting underneath this shatland plate. So then we come up and right here at zero feet begins ground above sea level. So that little peak that I’ve highlighted, let’s zoom in on that.

That little peak is that island right there. It looks like it’s part of these little set of islands from deception island to Livingston Greenwich Islands and so forth through here up to Penguin Island. So these are a set of islands that bound South America to Antarctica and you can deduce from these volcanoes that this is resulting from the subduction here as we talked in class on Monday. Therefore it’s a volcanic island arc with oceanic lithosphere subducting under oceanic lithosphere. Then we come back and on the backside of it is a low spot. This is a little oceanic depression, a small basin that’s resulting because this is higher. So you’ve got some offset of lower. You keep going south and again at zero feet or sea level is actually meters. You get into the Antarctica Antarctic crust. So that’s how you can use these cross sections at an angle to your profile line to understand what’s going on. In this case obviously you recognize that this line I’ve evaluated at an angle to my line doesn’t really cross cut my yellow line but as I explained it’s maybe a bad choice of an example because we’re covered in ice. But I did do one over here and I’m going to bring that elevation profile up and that is this guy at an angle and it goes through what’s actually called the Adelaide Island. And you can use your cursor on the profile to follow where you are on the map if you follow that red arrow. And right here where I’m going to highlight red starts above sea level and you’re traversing across an island. This area that’s flat is covered by ice therefore there’s no resolution.

So that’s how you can use what I’ll call transverse lines which means at an angle to your profile line to understand what’s going on. Now if you keep this in mind this part of how I didn’t read that’s above elevation let’s come and look at that in this profile line and you can see that that is right here.

So now I want you to know this is pretty small right in terms of the distance from the left to the right that this this profile line covers because we’re covering this entire part that’s an ocean basin up into a continental slope and shelf. And then at this point right here we get into just below sea level so this is our continental shelf and then we get on to the Adelaide Island and then we stay on there through the peninsula of Antarctica covered with ice that’s why it’s flat and then we go back down into the continental shelf slope and then the ocean basin. Okay so that’s the kind of interpretation you’re going to be doing. Now I want to take you back to my document I’m going to have provided you and show you what I’ve just explained in my document. So what I just explained in this video is what I’ve documented here in the assignment. So we’re calling these sort of many sections but I’m going to discuss it at the ones at a slightly different angle. So when you did your profile line you did the whole line which covers you know something like upwards of 2000 kilometers they’re long right. Well this first profile line I’ve shown you here is number one label number one is the yellow line from here to here about 2000 kilometers from west to east. Well my little blue line here is profile line number two and that scoop this up a little bit.

Is this bottom profile line so the yellow line is 2000 kilometers the blue line is 220 kilometers. So what I want you to notice is how much more resolution or detail you get when you make a shorter line. So you’re going to have to do this as well you’re going to make these many lines along your profile line that center on your areas of interest. So in this an article peninsula profile line I want to look at this island and I want to understand what’s happening there. So I’ve made a smaller line and when you compare it to the yellow line the bigger line you can see what I’ve highlighted here in blue. This thin sliver which covers basically about 50 kilometers and I can do the math because this is 750 to 1000 so that’s 250 kilometers divided by 5 would be about 50 kilometers each. So this blue sliver is about 50 kilometers from left to right or west to east. And then when I do my many blue line and look at it in number two profile line this is my 50 kilometers and you see how much more detail you get. You can look at the height difference the elevation change across the island and so forth. So you’ll need to do that across your AOIs. Similarly just as a second example I’ve highlighted this little depression here in green and that is this depression. And so you can you can barely see I’ll zoom in here that at the bottom of this thing there is in fact a little change in elevation you see how it’s deeper right above my cursor and then a little more shallow. Well if you come down here to this zoomed in section or many map many section you can resolve that change in elevation much greater.

So that are some that is some details about what’s your task to do in part two. You will have to read the assignment to see explicitly what you’re going to present to me as I’ve outlined it in there. But in general you’re going to state your five observations which are going to be centered on your three areas of interest you’re going to define. So you need three areas of interest and I have to see have a redundant typo here I’m going to clarify that so we’ll scroll up your three areas of interest in your five science based observations. So I hope you can see how these two things are related and we can back up and go through this too in your five science based observations. You are going to basically list five statements about your profile line using your own observations. So ideas I’ve given you and these are not your ideas do not have to be limited to this. They will involve the ideas are doesn’t involve convergence or subduction divergence or a spreading rage is their lateral movement i.e. a transform fault is their mountain building are their volcanoes. What interesting textural features do you see on the sea floor are they sea mounts are they future islands or are they currently islands meaning above sea level. How do they form evaluate some major and or abrupt changes in elevation. What’s the highest point on your line what’s the lowest point what’s the significance of those are their major earthquakes. You can use it science based observation and make it a question like gosh I see this. I don’t know what’s going on possibly it could be X possibly it could be Y and I will help you flush that out. How do the low areas on your line develop conversely how do the high areas develop what is the current topography and how did it become that way. Are there major rivers and what do those tell you is the ocean basin your next to getting larger or smaller what’s the direction of movement. What will the area look like in a million years will the mountains be taller or are they done being built and they’re going to begin to erode like the Appalachians. One thing I want to point out is what I’ve highlighted in here is science based observations do not involve humanity like cultural historical anything related to what we humans have done to the continent. It also doesn’t involve necessarily the amount of population nor what the area covered now the area of covered might be significant. But if you see this one high point that hits it Medellina Medellin which is a city in Columbia. It’s named the city of eternal spring and has a population of 2.5 million in this area of 147.5 miles squared. That’s not earth science based observation and I hope you see that that’s not what we’re looking for we’re looking for observations more related to things that we’ve discussed to date and class. What you need to do is bullet point out this evidence you see within these observations describe them to me be as specific as possible and you’re going to continue to hone through these and narrow down and make them more specific as we move through the next few weeks. Again you’re going to describe what processes are going on or have occurred which resulted in what you’re observing try to use what we’ll call your earth science vocabulary. I’ll help you with that too but you can begin doing your own work on that. You can evaluate the topography to help you understand this and by that I mean you can look at the elevation changes and quantify those. You can discuss the regional strike and dip are the mountains striking parallel to the subduction zone most likely yes or the volcanoes distributed along that same strike are they steeply dipping meaning is there a great change in elevation from the top to the bottom. And you can read these here and then okay so good so good luck and as always please reach out to me if you have any questions.