A great variety of depositional and erosional landforms can develop along shorelines. A major control on the appearance of the shoreline is kind of rock acted upon by water and wind. Volcanic rock cliffs are usually steep. Granite normally erodes into rounded domes, while limestone may form nearly vertical cliffs. The type of material at the shoreline has a significant effect on the rate of erosion. Techniques that try to prevent beach erosion revolve around methods to limit the removal of sediment along specific areas of the coast or involve adding material to areas undergoing erosion.
Examples include jetties, groins, and breakwaters. Jetties and groins are artificial structures built perpendicular to the shoreline to prevent longshore drift. Breakwaters are artificial structures built parallel to the shoreline in order to protect the shore from wave action.
Unfortunately, nearly all these methods have shortcomings. Skip to main content. K-5 GeoSource. PDF version. How beaches form The accumulation of sediment along a coast produces depositional landforms. Coastline changes Coastlines are constantly changing due to the action of waves, currents, and tides. The Marshall Islands is home to some pristine coral reefs, but storm-driven waves could erode these natural coastal barriers.
A new wave abrasion simulator offers insights on coral erosion rates that could aid coastal planning in this low-lying island nation and elsewhere. Some of the most complex insights in marine science are no match for the communicative power of art. Check out these five recent collaborations between ocean scientists and artists.
In the s, the Cape Cod Mosquito Control Project dug approximately 1, miles of ditches across marshes on the Cape to drain their water and reduce the number of ponds where mosquitoes can breed. Woods Hole Oceanographic Institution biogeochemist Amanda Spivak is studying how this and other management decisions have changed the ability of coastal marshes to store carbon and protect against sea level rise.
A research team predicts potentially big changes within the next century that would have significant impacts on those who live on or near the coast. Scientists at Woods Hole Oceanographic Institution share their field-tested experience, training graduate students on methods and instruments to collect data in the coastal ocean.
On Aug. The numbers are staggering: More…. Scientific insight into real-world problems such as rising sea level, storm activity, and climate change. Understanding and modelling waves, currents, and sand movement in the nearshore, surf, and swash. How fast could sea level rise? How would rising sea level affect our coastline? These questions, and many others, were the subject of this Morss Colloquium.
He uses techniques that span isotope geochemistry, next generation DNA sequencing, and satellite tagging to study the ecology of a wide variety of ocean species. He recently discovered that blue sharks use warm water ocean tunnels, or eddies, to dive to the ocean twilight zone, where they forage in nutrient-rich waters hundreds of meters down. Born in New Zealand, Simon received his B. With much of his work in the South Pacific and Caribbean, Simon has been on many cruises, logging 1, hours of scuba diving and hours in tropical environs.
He has been a scientist at Woods Hole Oceanographic Institution since Gregory Skomal is an accomplished marine biologist, underwater explorer, photographer, and author. He has been a fisheries scientist with the Massachusetts Division of Marine Fisheries since and currently heads up the Massachusetts Shark Research Program. For more than 30 years, Greg has been actively involved in the study of life history, ecology, and physiology of sharks.
His shark research has spanned the globe from the frigid waters of the Arctic Circle to coral reefs in the tropical Central Pacific. Much of his current research centers on the use of acoustic telemetry and satellite-based tagging technology to study the ecology and behavior of sharks. He has written dozens of scientific research papers and has appeared in a number of film and television documentaries, including programs for National Geographic, Discovery Channel, BBC, and numerous television networks.
Key concepts Oceans Beaches Geology Erosion Introduction A day at the beach is a wonderful way to spend time with your family and friends. You can swim, play games and build sand castles. But have you ever wondered how the beach you are standing on came to be? How, for example, did all of that sand get there?
Beaches are formed and continually changed by the ocean's waves moving rock particles onshore, offshore and along the shore. In this activity, you can investigate how beach formations are made by some parts of a beach that can resist erosion from the waves more than other parts.
Background A beach is a geologic formation made up of loose rock particles such as sand, gravel and shell fragments deposited along the shoreline of a body of water. A beach has a few key features. The berm is the part that is mostly above water; this is the active shoreline. The top of the berm is known as the crest, and the part that slopes toward the water is called the face. At the bottom of the face there may be a trough and, further seaward, there may be sandbars parallel to the beach.
The erosion of rock formations in the water, coral reefs and headlands create rock particles that the waves move onshore, offshore and along the shore, creating the beach. Continual erosion of the shoreline by waves also changes the beach over time. One change that erosion can cause is the appearance of a headland. This is land that juts out from the coastline and into the water and affects how the surrounding shoreline is eroded.
Build up a beach with most, but not all, of the sand at the shallow end of the pan. Let the water and sand settle for five minutes. How has the beach changed during this time? Where is the shoreline the area where beach and water meet? If the waves get so big that water splashes out of the pan, make them smaller. How does the water swirl?
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