hello learners hope you are keeping well uh today we're going to look at the concept of slope and i must get my highlighter first all right the concept of slope and we're looking at different slopes etc all right it's part of your grade 11 geomorphology okay so let's save you data and let's get going okay i took a simple explanation or definition of a slope it's the rise or fall of the landscape so this is not a slope ah slightly a slope there but it's not a slope if it's horizontal but this is a slope this is a slope all right it sits at an angle okay now let's look at types of slopes we have primary slopes these slopes are formed by the internal forces of the earth example faulting and folding let's look at fort you know fault is a crack in the rock and what happens when false happens sometimes one part of the rock when cracks here can you see it one part of the rock subsides and when it subsides in that crack can you see a slope forming okay so it was there everything and there you see the slope forming you see the slope forming here sometimes you've done these features before i know all right there's two faults the middle piece comes down can you see the sides a slope forms okay so that's one way and that is 14 all right primary slopes okay that's how your strokes form then folding let me move my face a bit can you see here the rock was straight horizontal strata straight then there was forces applied to it this is compression yeah stress and compression pushing it what happens to the rock now it starts to fold can you see a slow form in there that's your slope forming all right so folding also creates created don't worry about all the names here at the moment but all we need to see how a fold is caused can you see it it's folding and therefore when it folds it causes it slow your primary slopes then we have slopes caused by erosion all right these slopes occur when land is eroded can be by wind by water over ice glaciers etc here we have one that is water so this surface may have sat like that and what did this river do it eroded into it and as it eroded here can you see it eroding okay it cut through right widening the top and the bottom stays narrow as it goes but if there's further erosion there's more whitening can you see our slope form all right so water eroded through ah spelling mistake through all right the land to create a gorge but this car just got slopes on it all right now of course this will go further eros you get further eroded all right and that's when we have our secondary slopes this results from erosion and weathering of the primary erosion slopes or the primary slopes so this will undergo further erosion making it wider and that's when we get our secondary erosion slopes okay have you got that right i know you can't answer me but i know you're shaking your heads then we get the deposition slope this forms when weathered material is deposited okay it gets deposited meteor gets wetted here in this desert region right it forms the sand you all right when material gets deposited here all right and as it gets deposited can you see how the slope all right that's your slope there through deposition and therefore you get your deposition slope okay right now let's go a little more into it then we get something as a gentle slope now see this land is not very steep it's lying very gentle even me at my age i can walk through this would ease up this here it's nothing for me right so this has a gradient of between 5 and 15 degrees not very steep okay when the gradient gets steeper if you look at my hand this is like this all right and then it can get steeper and the angle changes look at my hand can you see the angle changing so from there today so if i draw this this may be something like this okay gradient not very steep to the horizontal all right can you see it if i did this then i could see the gradient going like that that's steep okay so it's between 5 and 15 degrees it's a low angle slope very low angle to the horizontal can you see that's your horizontal the angle is very small so it's a low angle now we will be asked to identify sometimes slopes on a on a map topographic map which has contour lines etc how do we find this all right we'll notice here and when i show you the steep slope you will see the relationship between the two here we notice if you look at the contour lines the space between the contour lines the contour lines are further apart and you learn the further apart the contour lines the more gentle the area is okay so the further apart all right that's how you would see it on a contour map or on a topographic map showing you contour lines etc okay let's look at the next one a steep slope has a gradient of more than 15 can you see it more than 15 this is a high angle slope so if i draw my horizontal now i have to do my slope like that no more like this can you see all right so it's a high angle slow right a high angle slow can you see that high angle slow okay and you notice this whoa this is a bad slope right i think i'll make it up to here and then i'll stop okay but what do you notice on a map all right on a contour map topographic map with contour lines they are closer together now look at this can you see this the lines are closer together i want to go back to the other one look at here all the lines are further apart and again yeah close that together that's how you'll identify it on a topographic map with contour lines or a contour map all right this is how you will see it okay let's go to another one a concave slope i like to simple it's simple it's a rounded inward means it's rounded inward can you see it round it inward can you see that as it's going okay so it's rounded inward and it's steep at the top and gentle at the bottom so if i draw it let me draw another one and let's go let's make it a little better let me not embarrass myself can you see okay let me do that steep at the top gen collector bottom all right can you see that that is your concave shape it's rounded inward now on a contour map because it's steep at the top the contour lines are closer at the top and further apart at the bottom all right if we if we look at this situation you'll notice the contour lines are close at the top can you see this is the top okay but as we go to the bottom that's the bottom there notice what happens to the contour lines they become further apart close showing you steeper at the top bottom showing you gentle at the bottom steep at the top gentle at the bottom okay let's cut that then we look at the convex slope all right now this is rounded outwards okay i like these things around the inlet output grounded outward can you see there's a shape out to it here all right it's going out it's blowing out right now there goes my pen again outward okay i sometimes you get a more pronounced one like that okay but it's ballooning or rounded outward so it'd be the opposite now it's steep at the bottom and gentle at the top can you see it can you see it's gentle at the top and then when you come to the bottom it gets steep okay so on a contour map the contour lines are closer at the bottom and further apart at the top now this is the top can you see it it's further apart showing you gentle when we go towards the bottom it becomes steeper and that is why your contour lines are closer together it's it's simple learners to actually do this you can identify it on any topographic contour map if you learn this and look at the heights okay so we're teaching you the map work also okay significance of slopes now okay one of it settlements can be built there all right okay but it costs quite a bit inside many cases if it's formal housing being put on the slope to burn the foundations etc okay but let's not get into that i wish i had a house on the slope but let's not talk about that right they built on slopes for a aesthetic appeal i mean what a beautiful city in this area you understand to look down maybe there's an ocean there maybe there's something else there that looks very attractive let's not get into detail but it's a beautiful view right of the whole area also it could be situated on the north-facing slope people situate on a north-facing slope because it faced in the southern hemisphere especially right in the sun atmosphere i think i must put that in brackets sh sudden hemisphere because in the southern hemisphere the north-facing slopes receive more sunlight so it makes it warm especially during winter nice to have a warm area you understand it's beautiful to relax outside etc so that's another reason because of the sunlight the settlement settle in on that so we have settlements on slopes let's go on forestry can take place all right on steeper slopes trees can survive you can see that here look at these trees we also can get contour ploughing right where you're planting or plowing along contours of the land in order to minimize soil erosion and it takes place on slopes look at this all right you've got contours there's your your area there's another one farming so what happens is as the water comes down it doesn't just you know it collects chair and irrigates these surfaces can you see it where the crops are so you have contour plowing that can happen also on slopes so slopes are not just something that's useless there can be so many things you can use it for all right look at this recreation all right you can see these people here all right they take many things all right i think i'm so happy about this uh that i can see these people are hiking i love to hike you understand and this is definitely not me doing mountaineering but many things you can some people in the swiss alps they do skiing down there so it's used for a lot of things all right i think i just love contour plowing i just love it i have been repeating it yes so you don't need to worry about it okay you know contour plowing happens okay so but it's also used for recreation hiking mountaineering uh whatever you can find those things skiing so slopes are important for that and as again i'm saying i'm pointing out my contour ploughing again all right which i did before this my apologies learners all right then building of infrastructure is a challenge especially building your railway lines your roads etc on slopes say so it is difficult to build on slopes all right so therefore what happens is it costs more okay so it's not slopes are not a huge advantage for building infrastructure but sometimes it can be built when you follow the contours of the land look at this look at this road here it's following the contours of the land all right so that you can't you can't it's impossible to build a railway line here all right it's not going to go up okay and my car definitely won't go up here you understand it won't even go here forget it okay even though those your dad's four by fours and whatever is going to be huge problem going up so we have to build according to the contours of the land or slope okay so it's four significances i gave you of course you need to look at the resources learners whatever the resource gives you don't just give generally say significance just give anything see if the resources got maybe people hiking then you know it's for recreation okay or contour plowing you see my favorite i repeated it under recreation also all right apologies then you know okay uh i hope you enjoyed this lesson all right and all the best goodbye