1 / 16

Introduction to Coastal Process

Introduction to Coastal Process. Introduction. ½ world’s population in coastal regions Coastal modification impacts humans and other organisms/plants Present-day climate change will modify coasts. LA Times. Class Focus. Shaping of Coastline Processes operating on coastline

beau-matthews
Download Presentation

Introduction to Coastal Process

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Introduction to Coastal Process

  2. Introduction • ½ world’s population in coastal regions • Coastal modification impacts humans and other organisms/plants • Present-day climate change will modify coasts LA Times

  3. Class Focus • Shaping of Coastline • Processes operating on coastline • Changes along the coast

  4. More Specific Class Focus • Geology influence on coastal features • Nearshore processes • Fluvial processes • Sea level and climate • Sediment transport

  5. Some Terminology • Shore • Zone between low tide level & upper level of wave action. In our coasts, usually cliffs • Consists of foreshore, backshore, and nearshore

  6. Terminology • Shoreline • Water’s edge • Beach • Loose sediment (sand, gravel, boulders) accumulation • Mostly in backshore • Coast • Includes shores & nearshore to where waves break • Inland to where marine influences cease—cliffs, lagoons etc • Will vary in width • Where air, sea, water mix • Influenced by • Tectonics and lithology • Oceanographic processes—waves, tides, current • Sea level • Atmospheric processes—wind, precipitation • Coasts shaped by • Erosion • Deposition

  7. Ancient Coastlines • Sedimentary geologists • Reconstruct sedimentary environments • Ancient shorelines preserved throughout rock record • Help reconstruct ancient sea level rise and fall • Global record vs local record • Climate vs tectonic activity Picasaweb.com Oysters, Vaqueros Fm.

  8. Shape of coastlines • Straight or curved • E.g. san Andreas Fault in San Francisco area • Madura, Indonesia • East Madagascar Based on U.S. Geological Survey map

  9. Terminology • Coastline • Land margin at normal high tide • Difference between coastline and shoreline?

  10. Straight Coastlines • Madagasgar • Indonesia

  11. Some basic relationships • Headlands & promitories= resistant rocks • Bays = less resistant rock or tectonic folding, tilting • Embayed coastline with valley mouth usually submerged • E.g. east U.S. coast • Gulf coast formed by deposition = curved coast Marin Headlands, San Francisco area Photo (c) Andrew Alden

  12. Gulf coast and Eastern Seaboard ECB.org NASA

  13. Rounded Bays • Submerged volcanoes • E.g. Santorini • Hanauma Bay, Oahu Hanauma Bay and Koko Crater at Koko Head, Oahu NASA

  14. Evolution of Coasts • Tectonic Processes • Separation of plates • Active tectonic processes—faulting and folding • Climate—wind, rain, weathering & decomposition, vegetation • Rising and falling tides

  15. Changing Coastline • Advancing • Sedimentation is greater than erosion • Emergence, uplift, sea level fall • Retreating • Erosion greater than deposition • Sea level rise • subsidence

  16. Rates of Coastline Change • Rapid • Storms • Lava flows • Earthquakes • Gradual • Longer termed changes • Tectonic uplift, sea level rise • Measure changing coastline • Maps, photographs, gps, etc.

More Related