How does EROSION work? - 4 types of erosion explained

Summary

Highlights

• The wind effortlessly transports sand, demonstrating how even gentle forces can gradually erode and reshape landforms. 🌬️
• Glaciers, though slow-moving, are powerful agents of erosion, capable of sculpting U-shaped valleys in mountainous regions. 🧊
• Ocean erosion, driven by wave action, persistently forms and alters coastal landscapes, eroding cliffs and creating beaches. 🌾
• River erosion involves both carving into mountains to create V-shaped valleys and meandering among plains, illustrating diverse topographical effects. 🌊
• Understanding erosion provides insight into natural landscape formation and the persistent power of nature's forces. 🌎

Key Takeaways

• Wind erosion can slowly shape landscapes over time, transporting and depositing sediments in new locations. 💨
• Glacial erosion carves out dramatic U-shaped valleys as massive glacial movements wear down mountainous terrains. 🏔️
• Ocean waves contribute to erosion by continuously crashing against coastal cliffs, reshaping coastlines over centuries. 🌊
• Rivers erode landscapes differently depending on whether they're in the upper, middle, or lower course, each carving unique geographic features. 🚤
• Erosion through a river has both vertical and horizontal impacts on landscapes, varying significantly based on geographical relief. 🗻

Overview

Chapters

• 00:00 - 00:30: Introduction to Erosion The chapter titled 'Introduction to Erosion' is part of a series on Landscapes, specifically discussing exogenic forces. Erosion is described as the continuous wearing down of rocks and land surfaces, which is facilitated by transporting agents such as wind, water, and ice. The chapter aims to explore these agents and their roles in the process of erosion.
• 00:30 - 01:30: Wind Erosion The chapter titled 'Wind Erosion' covers the concept of how wind contributes to the wearing down of landscapes. It begins with an example of lying on a beach when the wind picks up, causing sand to blow over and hit your body, illustrating how wind can cause erosion. The wind transports sediments, such as beach sand, using the force of its movement to smash those particles against surfaces, thereby causing erosion.
• 01:30 - 03:00: Glacial Erosion The chapter discusses the concept of glacial erosion, comparing it to wind erosion using an analogy of lying on a beach with sand circulating over the body. It explains how tiny sediments, over time, erode surfaces, similar to how wind erosion affects rocks significantly over hundreds of years.
• 03:00 - 03:30: Water Erosion Overview Wind erosion involves the breakdown of land by wind, while glacial erosion occurs when accumulated snow on mountains forms glaciers that slowly move down due to their own weight.
• 03:30 - 04:30: Ocean Erosion The chapter titled 'Ocean Erosion' discusses the impact of glaciers on the earth's surface. It explains how the immense weight of glaciers, which contain many sediments, acts to erode the ground beneath and around them. The movement of the glacier carries rocks and sediments. Only when the glacier eventually melts, which depends on global temperature conditions, does the extent of the erosion become visible.
• 04:30 - 06:00: River Erosion: Upper Course The chapter discusses the impact of glacial erosion on landscapes. When glaciers melt, they leave behind a distinctive u-shaped valley, which is a direct result of the glacier's wide and u-shaped form. This chapter explains how the process of glacial erosion is responsible for the formation of these u-shaped valleys.
• 06:00 - 07:30: River Erosion: Middle Course This chapter focuses on the process of river erosion, particularly in the middle course of a river. The discussion involves the formation of a U-shaped valley due to the river's erosive power. Additionally, the chapter distinguishes between two types of water erosion: river erosion and ocean erosion. In ocean erosion, waves containing smaller sediments like sand and clay impact the cliffs on the beaches, contributing to the erosion process.
• 07:30 - 09:00: River Erosion: Lower Course In the chapter titled 'River Erosion: Lower Course,' the mechanics of erosion are discussed, particularly focusing on how natural forces shape landscapes. The chapter details how the energy of ocean waves crashing into rocks contributes to erosion. This process is exacerbated by small particles of sediment that continually impact the landscape over time, wearing it down. The chapter explains that this continuous action results in notable changes to the beach and cliff landscapes, exemplifying the ocean's powerful capacity to erode. Furthermore, the chapter implies a parallel in how river erosion operates.
• 09:00 - 10:00: Conclusion The chapter concludes with a focus on the different forms of sediments found in rivers, such as pebbles, rocks, sand, and clay. These sediments play a significant role in shaping the landscapes around or below the river through erosion. However, the effect of erosion varies depending on the part of the river. The upper course, located high in the mountains, the middle course, positioned between the mountains, and how erosion functions in these distinct parts of the river are briefly examined.

How does EROSION work? - 4 types of erosion explained Transcription

• 00:00 - 00:30 hello and welcome back to another Geo explaining video and today we will continue on chapter 1 Landscapes we will look into another type of exogenic force erosion erosion is the continued wearing down of rocks and land surfaces by one of the transporting agents such as wind water and ice let's take a closer look at these agents and how they cause this erosion the
• 00:30 - 01:00 wearing down of the landscape first let's talk about wind erosion have you ever laid down on the beach on a nice sunny day and then all of a sudden the wind starts to pick up the sand wishes over your body and your face and it does kind of hurt this is how wind can cause erosion you see the wind is transporting other sediments in this case the sand from the beach and the force that it smashes all those
• 01:00 - 01:30 tiny sediments into your body causes your body to slowly get smaller now of course in this one minute or couple minutes that you lay on the beach and all this sand wishes over your face and your body you don't really get smaller but if there is a rock which is laying down there for over hundreds of years you can imagine how strong the wind erosion can be just look at this this is caused by wind erosion making it smaller
• 01:30 - 02:00 breaking down the land and this is how wind can cause erosion wind erosion second there is ice erosion or in better terms glacial erosion on top of the mountains snow has accumulated over the years and under the pressure of its own weight it forms ice a glacier these Glaciers are practically frozen rivers because very slowly they move down
• 02:00 - 02:30 you can kind of imagine how heavy all this ice must be so the weight of the glacier pushes into the ground the heavy Glacier with many sediments in it wears down the surface below and around the glaciers and brings with it a lot of rocks and other sediments only when the glacier melts which can take a very long time depending on the global temperature it becomes visible how the glacier has
• 02:30 - 03:00 worn down the landscape as when the glacier melts what is Left Behind is a large Valley and a glacial Valley is easily noticeable because the Glaciers are very wide and have kind of this u-shape so the valley itself also has this u-shaped form we call these types of valleys u-shaped valleys and this is how glacial erosion causes
• 03:00 - 03:30 the land to wear down and in the end you are left with a U-shaped valley next there is water erosion but we need to divide water erosion into two categories there is the river erosion and there is the ocean erosion with ocean erosion the waves that crash into the Cliffs of the beaches are also filled with smaller sediments such as sand and clay and maybe tiny tiny
• 03:30 - 04:00 Pebbles so not only does the power of the wave that smashes into the Rock wear down the landscape but also all these tiny bits of sediment constantly push and push into the landscape over time this will have an eroding effect of the beach and the landscape the cliff the beach will wear down this is how the ocean can cause erosion on the other hand with River erosion
• 04:00 - 04:30 these sediments such as Pebbles and rocks and sand and clay have an eroding effect on the landscape around or below the river but the erosion caused by the river is different depending on where you are in the river so let's see how erosion works in the three different parts of the river you have the upper course which lay high in the mountains you have the middle course which lay between the mountains and the
• 04:30 - 05:00 flat lands at the end and there is the lower course which lay in the flat areas next to the ocean these areas are also known as planes because they're very plain the river courses are kind of similar to a slide in the upper courses in the beginning the river goes really Steep and fast in the middle courses it kind of cools down and then in the lower courses you are almost flat and end up in the ocean so let's see how erosion works in the three different courses first the upper course
• 05:00 - 05:30 here the river starts somewhere in the top of the mountains due to Melting snow or rainfall or there is a spring from underground water due to gravity water will always try to flow down to the lowest point which usually ends in the ocean but in the mountains there's not much space to go around because there's lots of relief so the river finds the best way possible to go down and because of the high
• 05:30 - 06:00 speeds in the upper course the river is powerful enough to still bring the bigger sediments with it such as rocks and pieces of cobbles these sediments scrape over the bottom of the riverbed carving out and wearing down the landscape below the river and if you do this over hundreds and hundreds of years the river will kind of cut itself in into the mountain and this way you can get a valley but not as wide as a
• 06:00 - 06:30 glacial Valley because glaciers were very wide but rivers are usually very thin in the upper course so it is a very pointy Valley making it a v-shaped valley so in the upper course erosion happens usually vertically into the mountains trying to bring down the mountain and finding the fastest way down to the ocean then we enter into the middle course the speed and thus the power of the river has gone down a
• 06:30 - 07:00 little bit because of this the river is not strong enough to bring the bigger sediments such as the cobbles and the rocks that we were talking about in the upper course so they have sedimented down this is why you usually find bigger rocks alongside the river when you are in the mountains in the middle course the landscape consists mostly of Hills so there is still some relief but it's not as much as in the upper course here the river will still cause vertical erosion still trying to go down towards
• 07:00 - 07:30 sea level but because there is more space due to a lower relief the river has more space to go left and right causing horizontal erosion and in the middle course you will mostly find medium-sized sediments such as Pebbles which have been brought down or broken down from the upper course but in the middle course the power of the river goes down and so the Pebbles will also fall down and finally we have arrived
• 07:30 - 08:00 into the lower course the speed and as the power of the river is at its lowest here and because the power of the river the strength of the river to carry sediments is so low it will mostly have sand and clay falling down and as the lower course mostly consists of flat planes which are almost as high as the sea level There is almost no vertical erosion anymore because we are already
• 08:00 - 08:30 on one of the lowest points and because it is so flat the river has a lot of space to go horizontally this is why why you can find lots of bending in the rivers in the lower course and also why you can find sand and clay sediments into the lower course and this is how River erosion works in the upper middle and lower course of the river so to summarize everything that we've learned today you now know what erosion is in which four ways erosion Can Happen by
• 08:30 - 09:00 wind glaciers the ocean or the rivers how each of these types of erosion work how River erosion is different depending on where you are in the river which course of the river you are and why you can find mostly sand at the ends of the river near the beaches or the dunes thank you guys for watching I hope you learned something new today and I'll see you in class or in the next
• 09:00 - 09:30 video goodbye