Erosion and Deposition Table of Contents Wave Erosion

Erosion and Deposition Table of Contents Wave Erosion Ms. De Los Rios 6 th Grade

Vocabulary Ch. 4. 3 1. Headland- A part of the shore that sticks out into the ocean. 2. Beach- Wave-washed sediment along a coast. 3. Longshore drift- The movement of sediment along a beach. 4. Spit- A beach formed by longshore drift that projects like a finger out into the ocean.

How Do Waves Cause Erosion and Deposition? Pg. 134 How do the waves get their energy from? ? Waves contain energy and are formed by winds. When wind contacts waves= transfers some energy to the waves. How does waves shape the land? Waves shape the coast through erosion by breaking down rock and moving sand other sediment.

2 Types of Wave EROSION 1. One way waves erode is by impact Waves impact= hits rocks with force and they begin to crack, with time it breaks them. 2. Waves also erode by abrasion Abrasion= waves carry sediment (sand & gravel) and as the waves moves & hits land, the sediment wears rock away. pg. 135

Headland pg. 135 What is a headland? A headland is a part of the shore that sticks out into the ocean • • • Waves coming to shore gradually change direction. The change occurs as different parts of a wave begin to drag on the bottom. The energy of these waves is concentrated on headlands. Headlands are made of harder rock that resists erosion by waves. But over time, waves erode the headlands and even-out the shoreline.

Wave Erosion Shade in the arrows that indicate where the greatest energy of the waves is concentrated. pg. 135

Landforms Created by Wave Erosion pg. 136

Landforms Created by Wave Erosion pg. 136 How is a Sea cave, Wave-cut cliff, Sea arch & Stack created? • Ocean waves that hit a steep, rocky coast erode the base of the land there. Where the rock is softer, the waves erode the land faster. Over time the waves may erode a hollow area in the rock called a sea cave. Eventually, waves may erode the base of a cliff so much that the rock above collapses. The result is a wave-cut cliff. • A sea arch is another feature of wave erosion that forms when waves erode a layer of soft rock that underlies a layer of harder rock. If an arch collapses, a pillar of rock called a sea stack may remain.

Deposits by Waves pg. 136 Deposition occurs when waves slow down, causing the water to drop its sediment. Waves shape a coast when they deposit sediment, forming coastal features such as beaches, barrier beaches, sandbars, and spits. (B, BB, S, S) A beach is an area of wave-washed sediment along a coast. The sediment deposited on beaches is usually sand. Most sand comes from rivers that carry eroded particles of rock to the ocean.

Deposits by Waves pg. 136 -7 As waves repeatedly hit the beach at an angle, some of the beach sediment moves down the beach with the current, in a process called longshore drift. One result of longshore drift is a spit, a beach that projects like a finger out into the water. Incoming waves carrying sand may build up sandbars, long ridges of sand parallel to the shore. A barrier beach is similar to a sandbar, but forms when storm waves pile sand up above sea level forming a long, narrow island parallel to the coast.

Wave Erosion The Changing Coast What are the different landforms called? Were they formed by erosion or deposition?