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Sc.912.e.6.4 Analyze how specific geologic processes and features are expressed in Florida and elsewhere. Earth Structures - The scientific theory of plate tectonics provides the framework for much of modern geology. Over geologic time, internal and external sources of energy have continuously altered the features of Earth by means of both constructive and destructive forces. All life, including human civilization, is dependent on Earth's internal and external energy and material resources. 16.3 Shoreline Processes and Features • • • • • • Chapter 16: The Dynamic Ocean Online Field Trips Chapter Quiz Study Guide Summary (PowerPoint presentation) Web Quest: Will I Be Treading Water? Web Resources – Ocean Circulation: Links on ocean currents – Ocean Movement: Waves and Tides: Links on ocean waves – Beach and Shoreline Processes: Links on coastal changes • Animations DAY1 • How are sediments along the shoreline moved? • By which processes do shoreline features form? • What structures can be built to protect a shoreline? • What is beach nourishment? Key Terms: • Wave refraction – The bending of waves • Spits – Elongated ridge of sand • Tombolos – Ridge of sand that connects an island to the mainland or another island Key Terms: • Sandbar – A ridge formed by ocean currents depositing sand near the shore. • Beach nourishment – Addition of sand to the beach 16.3 Shoreline Processes and Features Forces Acting on the Shoreline A beach is the accumulation of sediment found along the shore of a lake or ocean. Waves along the shoreline are constantly eroding, transporting, and depositing sediment. Many types of shoreline features can result from this activity. 16.3 Shoreline Processes and Features Forces Acting on the Shoreline Wave Impact • The impact of large, high-energy waves against the shore can be awesome in its violence. Each breaking wave may hurl thousands of tons of water against the land, sometimes causing the ground to tremble. Abrasion • Abrasion is the sawing and grinding action of rock fragments in the water. • Abrasion is probably more intense in the surf zone than in any other environment. CHAPTER 16 CHAPTER HOME Wind, Waves, and Currents VOCABULARY beach sandbar fjord 16.3 Shoreline Features Waves affect the shoreline by eroding and depositing materials. Sea cliffs, sea caves, sea arches, and sea stacks result from shoreline erosion. Sea cliff Longshore current Sea arch Sea stack SECTION OUTLINE Look at this picture: What could have caused this? Why is it so smooth? What will most likely happen to the trees on top of this cliff? DAY 2 • Fill in the following concept map Wave Refraction Causes this in bays is defined as causes this on headlands 16.3 Shoreline Processes and Features Forces Acting on the Shoreline Wave Refraction • Wave refraction is the bending of waves, and it plays an important part in the shoreline process. • Because of refraction, wave energy is concentrated against the sides and ends of headlands that project into the water, whereas wave action is weakened in bays. Wave Refraction • What is wave refraction and what are its effects? Wave Refraction Causes this in bays is defined as Bending of waves deposition causes this on headlands erosion DAY 3 Depositional Features Match term to area in picture Spits, Bars and Tombolos CHAPTER 16 CHAPTER HOME Wind, Waves, and Currents VOCABULARY beach sandbar fjord 16.3 Shoreline Features Waves affect the shoreline by eroding and depositing materials. Sandbars, spits, baymouth bars, hooks, lagoons, and barrier islands result from shoreline deposition. Lagoon Baymouth bar SECTION OUTLINE Spit Longshore current Shoreline Processes and Features Depositional Features Spits, Bars, and Tombolos • Where longshore currents and other surf zone currents are active, several features related to the movement of sediment along the shore may develop. - A spit is an elongated ridge of sand that projects from the land into the mouth of an adjacent bay. - A baymouth bar is a sandbar that completely crosses a bay. - A tombolo is a ridge of sand that connects an island to the mainland or to another island. Evolution of Shoreline Features Match term to area in picture; Spits, Bars and Tombolos 16.3 Shoreline Processes and Features Depositional Features Barrier Islands • Barrier islands are narrow sandbars parallel to, but separate from, the coast at distances from 3 to 30 kilometers offshore. Barrier Islands DAY 4 • Create a Venn Diagram for helpful and harmful effects of Beach Nourishment Shoreline Processes and Features Stabilizing the Shore Protective Structures • Groins, breakwaters, and seawalls are some structures built to protect a coast from erosion or to prevent the movement of sand along a beach. Beach Nourishment • Beach nourishment is the addition of large quantities of sand to the beach system. Miami Beach Before and After Beach Nourishment Day 4 • FCIM Assessment