Answer: The causes of ocean currents include wind, water temperature/salinity and natural disasters.
Explanation:
A current or circulation is the unified movement of water across the ocean. A Surface current affects the topmost layer of seawater and is defined by the direction of the wind while Deep Currents reach the sea floor though a combination of surface currents and landforms.
Water temperature and salinity cause currents by changing water density which in turn results in deep ocean currents circulating the seawater.
Other conditions that cause strong currents are storms and earthquakes which introduces particles into the seawater.
The thing that makes coastal plains unique is that they are flat, low-lying pieces of land next to the ocean.
Answer:
Deep-sea trenches generally lie seaward of and parallel to adjacent island arcs or mountain ranges of the continental margins. They are closely associated with and found in subduction zones—that is, locations where a lithospheric plate bearing oceanic crust slides down into the upper mantle under the force of gravity.
Explanation:
"The result is a topographic depression where the oceanic plate comes in contact with the overriding plate, which may be either oceanic or continental. If the overriding plate is oceanic, an island arc develops. The trench forms an arc in plan view, and islands with explosive volcanoes develop on the overriding plate. If the overriding plate is continental, a marginal trench forms where the topographic depression appears to follow the outline of the continental margin. Explosive volcanoes are found there too"