a beach by another name

After doing this lab we got familiar with coasts. Primary coasts are generally young and are shaped by terrestrial processes, including erosion, river/stream deposition, glaciers, volcanic, and tectonic movements. Secondary coasts are shaped mainly by marine erosion or deposition due to wave action, sediment transport by currents, or building activities of certain organisms, generally these coasts are older. Primary coasts can be formed by land erosion, land processes, deltas, volcanic coast, and fault coasts. Secondary coasts form sea cliffs, sea caves, sea arches, sea stacks, and wave-cut platform.Bar-built estuaries are formed when sandbars build up along the coastline. These sand bars partially cut off the waters behind them from the sea. Bar-built estuaries are usually shallow, with reduced tidal action. Wind is frequently the most important mixing tool for the fresh and salt water. This type of estuary is common along the Texas and Florida Gulf coasts (East Matagorda Bay), in The Netherlands, and in parts of North Carolina (Albemarle Sound and Pamlico Sound). tectonic estuary is when the rapid movement of the Earth’s crust causes a large piece of land to sink, or subside, producing a depression or basin. These drastic changes typically occur along fault lines during earthquakes. If the depression sinks below sea level, ocean water may rush in and fill it. The same geological forces that create these depressions often form a series of natural channels that drain fresh water from nearby rivers and streams into these newly formed basins. The mixture of seawater and fresh water creates a tectonic estuary. Estuaries formed in this manner are typically very deep and surrounded by mountainous areas. San Francisco Bay, on the West Coast of the United States, is an excellent example of a tectonic estuary.estuaries are dramatically influenced by tides. When the tide is out, many aquatic creatures retreat into protective postures. Clams can close their shells, worms stay underground, while other creatures sleep. The change in temperature, the exposure to air and the vulnerability of being active during daytime are all reasons why some creatures are only active at night. Of course, some animals, like birds, are active during the low tide daytime because the supply of food is easier to get to.At night when the tide returns the estuary comes alive. The returning sea water floods and submerges creeks, salt marshes, mud flats, mangroves, and estuaries. The water brings protection from predators. Many estuary creatures become active only at night.Two ecosystem services that estuaries provide are water filtration and habitat protection. Estuaries produce more food per acre than the most productive mid-western farmland.Dynamics of Coastal Systems is about the dynamic interaction between water motion and seabed topography, which affects the natural response of coastal systems to change in external conditions and to human interventions — from the scale of seabed ripples up to the scale of entire barrier and delta systems. The book highlights major concepts developed during the past 50 years for the description of current-topography, tide-topography and wave-topography interactions. It provides simple analytical tools and models for diagnosing and predicting coastal response to change, with references to a great variety of coastal systems around the world. These concepts and tools are crucial for sustainable management of beaches, deltas and coastal wetlands.