Presentation on theme: "Chapter 16 The Marine Environment. The Shore The shore is the area of land between the low tide and area affected by storm waves."— Presentation transcript:
Chapter 16 The Marine Environment
The Shore The shore is the area of land between the low tide and area affected by storm waves.
Erosional Shoreline Features Headlands are eroded by wave action to produce wave cut platforms
Longshore Currents Longshore currents move large amounts of sediments along the shore.
Depositional Shoreline Features Seashores are in a constant state of change. Sediments are moved and deposited by longshore currents
Human Impacts Humans modify the shoreline to try to control beach erosion
Use of groins to control erosion
Changes in Sea Level Climate change caused by global warming is causing sea levels to rise: – Thermal expansion: global temperature increases, causing seawater to heat up and expand, leads to rising sea level – Melting glaciers adds to ocean volume Tectonic forces (uplift and sinking) can affect sea level in local areas
Seafloor Features Continental margin: where continent meets ocean
Continental Margin Continental shelf: average depth 130 meters; width can vary from a few to hundreds of kilometers Continental slope: the true edge of the continent; deep submarine canyons Continental rise: the base of the continental slope
Abyssal plains: flat parts of the ocean floor Deep-sea trenches: deepest parts of the ocean, created by ocean plates sliding under other plates Mid-ocean ridges: undersea mountain ranges, created by two plates being pushed apart Other features: seamounts, guyots, hydrothermal vents
Marine Sediments Terrigenous (deep-sea mud): originates on land Biogenous (oozes): forms from living organisms Hydrogenous: elements that precipitate directly from seawater. Ex: manganese nodules