Geo3100 - Study Guide Chapter 11

Exam 4 Study Guide: Part 1 Chapter 11: Coastal Hazards Instructions: Use the chapter 11 reading and lecture materials to answer the following questions Some questions have multiple parts so carefully read the questions and provide detailed and specific responses. Generally, the difference between a good grade and a poor grade on an assignment is based on whether or not the questions were answered completely. The purpose of this assignment is to test your understanding of course materials covered from Chapter 11. Additionally, this assignment doubles as Part 1 of the Exam 4 study guide. 1. How do tectonics influence coastlines? (1 pt) 1. The topography, climate, species, and occurrence of natural hazards are influenced by tectonics. Where coastlines are close to active convergent tectonic boundaries cliffs and rocky shores are present such as the west coast of the US. When a coastline is not close to convergent tectonic boundary the coastline is passively influenced and has wide continental shelves. 2. What are three factors used to determine the size of waves? (1 pt) 1. Speed of wind 2. Duration of Wind 3. The Fetch of the wave 3. Define wave height, wavelength, wave periods, wave energy, and wave motion. (1 pt) 1. Wave height: the distance from the crest of the wave to the trough of the wave. The crest is the high point of the wave and the trough is low point of the wave. 2. Wavelength: is the distance from crest to crest of the wave or trough to trough of the wave. 3. Wave Periods: is the time it takes for waves to move past a specific point. It is measured as time between crests and the point. 4. Wave Energy: Is proportional to the square of the wave height, it is also related to to the motion of a wave. 5. Wave Motion: is circular in the open ocean with decreasing circle diameter as depth increases. This makes for larger cycles towards the surface of ocean water. 4. What is wave refraction? (1 pt) 1. This is the slowing and bending of waves in shallow water. This happens as a wave approaches shore as it slows upon reaching the shore then this slowing causes the wave front to bend. 5. Describe how sediment is transported along coastlines. (1 pt) 1. There is a zone of littoral transportation within the swash zone and surf zone of the beach. The transport of sediment occurs parallel to the coastline shore as directed by longshore drift. Sediment and other materials are then carried up and down by beach and in a zig-zag pattern through the swash zone. 6. How are rip currents produced and how can you escape from one? (1 pt) 1. A buildup of waves between the longshore bar and swash zone of a beach leads to the development of rip currents. The water here becomes concentrated in a narrow zone forming the current. The action of a rip current pulls swimmers away from shore so it’s dangerous to swim against the current as it becomes exhausting.