Skip to main content

What is the difference between a rift valley and a mid-oceanic ridge?

As tectonic plates move they sometimes move away from each other at divergent plate boundaries. The space left behind opens a large hole between the plates that is either filled with sediment, magma flowing from the mantle, or water. The major difference between different types is what type of plate the divergent boundary is between. 


If the boundary is found between two continental plates you are left with a rift valley. This leads to steep...

As tectonic plates move they sometimes move away from each other at divergent plate boundaries. The space left behind opens a large hole between the plates that is either filled with sediment, magma flowing from the mantle, or water. The major difference between different types is what type of plate the divergent boundary is between. 


If the boundary is found between two continental plates you are left with a rift valley. This leads to steep mountainsides spreading apart from a widening valley. In the center of the valley either large gaps can form or the area will fill with water from water sources or rain creating rift lakes, much like what can be found in the African Rift Valley. Many lakes have sprung up in the valleys left behind as the plates there move slowly away from each other. 


If two oceanic plates begin moving away from each other it creates a mid-oceanic ridge. Continental plates are less dense, and thus float much higher on the mantle. Magma is usually much farther away, so it's rare to find a splitting continental plate seeping magma. On the other hand, oceanic plates are thin and dense, meaning magma is much more likely to flow to the surface at one of these splits. At the Mid-Atlantic Ridge, the boundary between the North American plate and the Eurasian plate, the spreading boundary is constantly seeping hot magma out of the mantle below. This creates a constantly growing mountain chain. 


The main difference between these two seismic structures would be what types of plates are creating the diverging zone and what is being created at the divide: a valley that may fill with water or sediment, or a growing mountain chain as magma fills the opening gap.

Popular posts from this blog

In chapter one of The Great Gatsby, what advice does Nick's father give him? How does this make him a good person to tell this story?

Nick says that his father advised him that, before "criticizing anyone," he "remember that all the people in this world haven't had the same advantages" as Nick.  As a result, Nick claims that he is "inclined to reserve all judgments," presenting himself to the reader as a fair and dispassionate arbiter of character, and thus, a reliable narrator.   The problem is that Nick immediately reveals himself as anything but reliable, as he then launches... Nick says that his father advised him that, before "criticizing anyone," he "remember that all the people in this world haven't had the same advantages" as Nick.  As a result, Nick claims that he is "inclined to reserve all judgments," presenting himself to the reader as a fair and dispassionate arbiter of character, and thus, a reliable narrator.   The problem is that Nick immediately reveals himself as anything but reliable, as he then launches into a discussion of how pe...
Post a Comment
Read more

How did the United States become an imperial power?

"Imperial power" is a bit of a vague label. It tends to mean several things at once, so let's unpack it. In the sense of "this country was built on conquest by force," the "imperial power" part of America actually predates the United States proper. The territories that would become the United States were imperial colonies, established by the great European empires of the 17th and 18th centuries. Much of the US Constitution and American governance generally goes back to England, history's largest and most successful imperial power, but vital aspects of American culture come from other imperial powers, such as France and Spain. Much of American culture comes from sources other than the old empires, but they were key influences on what the United States became. In the sense of "this country treats conquest by force as a fundamental component of its culture, economy and politics," the United States has always been an imperial power. Even earl...
Post a Comment
Read more

How and why does James Gatz become Jay Gatsby? Describe the young Gatsby/Gatz.

James Gatz, a poor Midwestern boy of probable Jewish lineage, becomes Jay Gatsby, a presumed WASP and wealthy socialite, when he moves to New York City and acquires his fortune. It is wealth that has allowed Gatz to transform himself into Gatsby. However, those who know his background (e.g., Daisy and Tom Buchanan) never allow him to forget that he is nouveau riche -- that is, an upstart who has just recently made his fortune,... James Gatz, a poor Midwestern boy of probable Jewish lineage, becomes Jay Gatsby, a presumed WASP and wealthy socialite, when he moves to New York City and acquires his fortune. It is wealth that has allowed Gatz to transform himself into Gatsby. However, those who know his background (e.g., Daisy and Tom Buchanan) never allow him to forget that he is nouveau riche -- that is, an upstart who has just recently made his fortune, whereas they arose from well-to-do families. Gatz became Gatsby through determination and discipline. At the end of the novel, the narr...
Post a Comment
Read more