Which of the following features is associated with a deep ocean trench?
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.
How did the Red Sea shown between Arabia and Africa in this figure form?
How did the Red Sea, shown between Arabia and Africa in this figure, form? Continental Rifting followed by seafloor spreading.
Which letter corresponds to the youngest oceanic crust?
30 Cards in this Set
| How did the Red Sea, shown between Arabia and Africa in this figure form? | Continental rifting followed by seafloor spreading |
|---|---|
| Where is subduction occurring on this map of South America? | B |
| On the accompanying figure, which letter is over the youngest oceanic crust? | D |
Which type of map or diagram would best indicate elevation of the land surface?
Which type of map or diagram would best indicate elevation of the land surface? Topographic map.
What happens at deep sea trenches?
Trenches are formed by subduction, a geophysical process in which two or more of Earth's tectonic plates converge and the older, denser plate is pushed beneath the lighter plate and deep into the mantle, causing the seafloor and outermost crust (the lithosphere) to bend and form a steep, V-shaped depression.
What caused trenches?
In particular, ocean trenches are a feature of convergent plate boundaries, where two or more tectonic plates meet. At many convergent plate boundaries, dense lithosphere melts or slides beneath less-dense lithosphere in a process called subduction, creating a trench.
What type of plate boundary is under the Red Sea?
Explanation: The Red sea is the result of a divergent boundary, while the Red Sea is not yet an ocean the process is very clearly the beginning of an Ocean. The mid atlantic ridge, is a divergent boundary.
What stage of a divergent boundary does the Red Sea represent?
This boundary is called a divergent boundary. The Red Sea is an example of stage B. Mature Ocean Basin (Full ocean basin) Stage C: Stage C, is when a large ocean has formed between two continental margins and spreading still occurs.
Why do you think that oceanic crust is much younger as compared with the continental crust?
The oceanic plate is subducted back into the mantle, thus destroying oceanic crust, to balance the crust being produced at the mid oceanic ridges. This is why all oceanic crust is much younger than the continental crust; it is constantly being recycled.
Which of the following components of the oceanic crust would you expect to find on the uppermost layer?
The topmost layer, about 500 metres (1,650 feet) thick, includes lavas made of basalt (that is, rock material consisting largely of plagioclase (feldspar) and pyroxene). Oceanic crust differs from continental crust in several ways: it is thinner, denser, younger, and of different chemical composition.
What type of map depicts the shape of the land surface by showing the elevation of the land surface with a series of lines called contours quizlet?
A maps depicts the shape of the land surface by showing the elevation of the land surface with a series of lines called contours.
Which of the following are indicated by contour lines in a map?
A topographic map illustrates the topography, or the shape of the land, at the surface of the Earth. The topography is represented by contour lines, which are imaginary lines. Every point on a particular contour line is at the same elevation. These lines are generally relative to mean sea level.
Why are ocean trenches important?
The place where the densest plate that is subducted is what is known as a subduction zone. This process makes things geological and dynamic elements. Many of these ocean trenches are responsible for numerous earthquakes at sea.
What is meant by an ocean trench?
Subduction zones create ocean trenches when one tectonic plate moves beneath another. An ocean trench is a geological structure which occurs undersea along the boundary of a tectonic plate. Specifically, ocean trenches form along subduction zones, in areas where one plate is being sucked under another.
Whats is a trench?
Definition of trench (Entry 1 of 2) 1a : a long cut in the ground : ditch especially : one used for military defense often with the excavated dirt thrown up in front.
What happens in the trenches?
With soldiers fighting in close proximity in the trenches, usually in unsanitary conditions, infectious diseases such as dysentery, cholera and typhoid fever were common and spread rapidly.
What type of plate boundary is Japan?
convergent plate boundary Japan has been situated in the convergent plate boundary during long geohistorical ages. This means that the Japanese islands are built under the subduction tectonics. The oceanic plate consists of the oceanic crust and a part of the mantle beneath it.
Is the Red Sea convergent or divergent?
The Red sea is the result of a divergent boundary, while the Red Sea is not yet an ocean the process is very clearly the beginning of an Ocean. The mid atlantic ridge, is a divergent boundary. The evidence of sea floor spreading is convincing that the ocean is spreading out in both direction.
Are trenches convergent or divergent?
In particular, ocean trenches are a feature of convergent plate boundaries, where two or more tectonic plates meet. At many convergent plate boundaries, dense lithosphere melts or slides beneath less-dense lithosphere in a process called subduction, creating a trench.
Why is oceanic crust younger near the oceanic ridge and older closer to the two continents?
Through mantle convection, the rich minerals of the mantle may be ultimately “recycled” as they surface as crust-making lava at mid-ocean ridges and volcanoes. Largely due to subduction, oceanic crust is much, much younger than continental crust.
How does the age of the oceanic crust vary from the plate boundary toward the continent?
Age of the crust: Comparing the ages of the oceanic crust near a mid-ocean ridge shows that the crust is youngest right at the spreading center, and gets progressively older as you move away from the divergent boundary in either direction, aging approximately 1 million years for every 20-40 km from the ridge.
Where are trenches found?
Trenches are found on the floor of the sea; however, their common name is deep ocean trenches because they are more often found in the deepest areas of the ocean. Trenches are formed in subduction zones where tectonic plates collide.
What is formed on top of one of the oceanic crust?
It is composed of the upper oceanic crust, with pillow lavas and a dike complex, and the lower oceanic crust, composed of troctolite, gabbro and ultramafic cumulates. The crust overlies the solidified and uppermost layer of the mantle. The crust and the solid mantle layer together constitute oceanic lithosphere.
What type of map depicts the shape of the land surface?
The distinctive characteristic of a topographic map is the use of elevation contour lines to show the shape of the Earth's surface. Elevation contours are imaginary lines connecting points having the same elevation on the surface of the land above or below a reference surface, which is usually mean sea level.
What specific type of map represents the distribution of rock units and geological features exposed on the surface?
Geologic maps represent the distribution of different types of rock and surficial deposits, as well as locations of geologic structures such as faults and folds.
What do contours on map indicates?
A topographic map illustrates the topography, or the shape of the land, at the surface of the Earth. The topography is represented by contour lines, which are imaginary lines. Every point on a particular contour line is at the same elevation. These lines are generally relative to mean sea level.
What does the line on the map indicate?
Contour lines show the elevation above sea level at a given point on your map. Relief shows the difference in elevation between two points on a map.
What are trenches geography?
Oceanic trenches are prominent long, narrow topographic depressions of the ocean floor. They are typically 50 to 100 kilometers (30 to 60 mi) wide and 3 to 4 km (1.9 to 2.5 mi) below the level of the surrounding oceanic floor, but can be thousands of kilometers in length.
What were trenches used for?
Trenches provided relative protection against increasingly lethal weaponry. Soldiers dug in to defend themselves against shrapnel and bullets. On the Western Front, trenches began as simple ditches and evolved into complex networks stretching over 250 miles (402 kilometres) through France and Belgium.
Where are the trenches?
Ocean trenches are found in every ocean basin on the planet, although the deepest ocean trenches ring the Pacific as part of the so-called “Ring of Fire” that also includes active volcanoes and earthquake zones.