Questions tagged [plate-tectonics]

The theory that Earth's outer shell is divided into several plates that glide over the mantle, the rocky inner layer above the core.

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3answers
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Movement of the Prime/Greenwich Meridian

The line on the ground at the Greenwich Observatory is itself on a tectonic plate that is moving, so is the prime meridian still 0 degrees, 0 minutes, 0 seconds? If not - what are the implications (...
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For slab rollback, what allows the subducting plate to begin descending at a steeper incline?

I recently learned about slab rollback, specifically of the Juan de Fuca plate subducting underneath the North American plate. From what I understand, the subducting plate over time begins descending ...
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How Do Plateaus Really Form?

Any time I hear the word "plateau", I usually associate it with the tallest in the world, Tibet. Anyone who looks closely at a map will see that the southern line of the plateau parallels the ...
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Effects of Mexican Earthquake in San Andreas Fault Line

Could the recent 8.1 Magnitude Earthquake at the Cocos and Nazca plates off the Mexican coast have a knock on effect to the Pacific and Juan de Fuca Plates further north at the San Andreas Fault Line?
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Could water pressure at the coast be the cause of continental drift?

For example the Northern Africa is getting closer to Europe, where the depth of the sea is lower than in south African coast Could it be that the water's pressure pushes the continent from where the ...
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How could this pyramidal Mountain have been formed?

How could this pyramidal peak have been formed in Antarctica? Little is known about it as far as I know but what is known is that its miles away from any existing plate boundary and its shape is also ...
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How did Australia separate from India?

So on a lot of maps of tectonic plates, it appears that India and Australia share a tectonic plate (hence the Indo-Australian plate). But in maps of Pangaea, India and Australia appear to have once ...
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How do tectonic plates move upward? [closed]

And also, can this push continents and land-masses upward as well?I have not been informed of the phenomenon of tectonic plates rising up. I am yet unable to find a satisfactory answer on the internet,...
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What causes jagged appearance of mountains in SE Asia?

For some time now, I've noticed that mountains in southeast Asia seem to be unusually "jagged" with steep surfaces. My basic knowledge of how mountains are formed (via geologic processes) tells me ...
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Lake Manasarovar v.s. Lake Rakshastal: fresh-water v.s. salt-water

In Tibetan Plateau, about 4600m elevation, If Lake Manasarovar and Lake Rakshastal ("lake of the demon" ) used to be the same lake, but due to the tectonic activity now they are separated to two by ...
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What fraction of Earth's crustal material survives the supercontinent cycle?

I know that things are not as simple, but for the sake of argument I'll assume a supercontinent cycle of $\sim$400 Myr periodicity is active on Earth. If that is the case, then my naive ...
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Is plate tectonics a hoax theory? How can tightly packed plates move?

Here are two questions I had ever since I first heard about plate-tectonics. How can the plates move? Before you suggest me some page to read about plate movement mechanics, let me clarify that I am ...
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Do divergent tectonic plates destroy mountains?

Tectonic plates meeting (convergent plates) form mountains. But if those plates change direction (which I am just assuming they can over time, I have no idea if it's true) and start pulling apart (...
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How do tectonics work on other planets?

What kind of tectonic plate activity exists on other planets in the solar system, or even large moons? Are there any deeper studies of what is needed for a planet or large moon to have tectonic ...
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Plate Tectonics: Is it possible to have an ocean-continent divergent boundary

I am procedurally generating planets for an open world space sandbox game. I am using a rough simulation of tectonic plates to create mountain ranges and other geological features. A planet surface ...
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The edges of the tectonic plates

I have read that the edges of the tectonic plates exist at places like: huge mountains and sea trenches, and I wondered if they exist at the mid-oceanic ridges?
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How does 10mm/yr of plate subduction provide enough material to create eruptions?

If the convergent boundary is only consuming 10mm of oceanic crust per year, it "seems" like that would provide insufficient material to cause the level of eruption generally observed. I am making the ...
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Pangaea, supercontinent formation and fragmentation [duplicate]

Is there a widely accepted model for the supercontinent cycles ? From the novice point of view, it is not obvious why the continents would be fragmented all over the earth as now, but 300 millions ...
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Speed of tectonic plate movement

I'm doing some research about tectonic plates and at which speeds they move and in which directions, because I'm writing a program to simulate the movement of the tectonic plates and also calculate ...
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Himalayas are currently rising. What will be the highest point they can reach?

Himalayas are currently rising about 5 mm/year. What will be the highest point they can reach?
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Need help understanding what an "isostatic model minimizing crustal deviatoric stress" means

Despite the background information coming from another body besides the Earth, the terms I would like to understand are historically geophysical in nature. Background: I just read today's news "...
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tectonic faults catalog for plot

I looking for a catalog (ideally in a ASCII file) of the major tectonic faults on earth, in order to plot some of them on a map Any suggestion ?
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Earthquakes at plate boundaries

I was looking into tectonic plate boundaries and earthquakes with pictures like these One thing that is quite obvious is that some of the plate boundaries have very thin zones of earthquakes, ...
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Earthquakes and mountain height

Tectonic plate motion is the main reason for earthquakes in Italy. I suppose that a large motion produces higher mountain (as Monte Bianco, Monte Rosa or Adamello) and strong earthquakes. But strong ...
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Fault representation

In most illustrations and diagrams of the types of faults, there is always something similar. I noticed that there is a side of the hanging wall and foot wall which is slanted. We're supposed to make ...
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Are the other causes of an earthquake (e.g. volcanic eruptions) the cause of the "sudden slip" which is the main cause of an earthquake?

I am to deliver an informative speech about earthquakes in class. However, I was not the first to talk about earthquakes and his discussion of the cause of earthquakes is different from mine. He ...
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What is difference between divergent boundary and hot spot?

As I know, both divergent boundary and hot spot are formed by rise of magma of convention, but divergent boundary is a line and hot spot is a point, is there difference between 2 kinds of rising magma?...
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How can we have "floating" and convection currents in a non-liquid mantle?

I've always thought the earth's layers were as follows: Crust, a few dozen KM think in most places Mantle, completely composed of liquid rock and molten metals, a few thousand KM thick Outer Core, ...
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How is dense magma able to rise and punch through continental crust?

I am trying to understand how a dense basaltic lava is able to rise and punch through the continental crust, such as in mantle plumes or the Great East African Rift. My understanding of plate ...
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Transform Boundary and its relation with Earth's rotation

I have read about all 3 types of boundaries in the book : "Essentials of Geography" by Lutgens et. al. But there is nothing mentioned about Transform Boundary and Earth's rotation effect on it. I ...
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Why is almost all the landmass on one side of the globe? [duplicate]

One side of the Earth is almost completely covered with water (the Pacific), while landmass is almost all on the other side. Is this coincidence or plays there something else? This difference is not ...
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If we assume the mega impact hypothesis for the formation of Moon, where on Earth is the impact point?

Given that Pangaea had C-shape can we assume that the point of impact was in the center of this C-shape? In modern world it would be under Tibet? Or should we assume the oldest shape of the ...
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Shouldn't India Get an Uplift Too?

For the past 50 million years, India has been crashing into mainland Asia, creating the Himalayan range and uplifting Tibet, north of the mountains, to a current average height of 4500 meters above ...
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What do continents "lay" on?

It's a simple question.. What do continents "lay" on? Do they float on water? or are they huge bodies that "emerge" from the sea floor/bed? are they connected to the bottom of the oceans? Hope the ...
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Can we see lava in a divergent tectonic boundary?

Can we actually see an orange line of lava if we look down to the crack of the divergent boundary of tectonic plates?
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How are small mountains created?

I understand that large mountain ranges like the Rockies are created by the tectonic plates moving. I live in Arizona and there are a lot of mountains here but from what I understand, there are no ...
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Why are oceans so deep?

Some areas of oceans are about 11 km deep. Is it because continental plates were moving away because of troughs in the middle from where new rock is formed? If so, why did it become deep? If not, what ...
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Are volcanoes formed from earthquakes?

I know that some earthquakes are caused by volcanoes and that some earthquakes can trigger volcanic eruptions close to where the earthquake is. But what if a great earthquake(8.0 or above) occurs and ...
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Future super-continent

What will the earth look like when the continents recollide? What will the climate be like? Assume global warming has been taken care of.
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Pangaea - Why did all the land mass form in one area?

The thing I find most interesting about Pangaea is that, if all the landmasses were connected, it leaves a massive amount of uninterrupted ocean everywhere else. It seems to suggest that there is a ...
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What was the likely composition of Earth's early crust (how did crustal composition evolve)?

Was the first crust entirely mafic (oceanic) crust which was later distilled via volcanic arcs along subduction zones to make felsic rocks or did the earth start with bits of felsic crust? Are the ...
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Continental collision – evidence left of river mouths and estuaries along the boundary?

Are there any examples of now completely landlocked former river mouths or estuaries that became so after continental collision? As an example, consider the closure of the ocean between India and the ...
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Can the crust be compared to an arch?

Since tectonic plates are held together by lateral stress, friction, and gravity, and the Earth is a sphere, they work just like a full-circle arch or full-sphere dome. So can the crust be compared to ...
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Are craters on Earth covered by vegetation?

When you look at other planets and moons in our solar system most of them have lots of craters. If Earth had no vegetation and water would it also look like this image of Charon? Image Credit: NASA/...
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Have the landmasses of North and South America ever been part of the same continent?

I know this question have been asked very often, but I could not find a proper answer around StackExchange, so I thought this might be a good place to ask: Have the landmasses of North and South ...
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Do "water-worlds" not have plate tectonics?

Water-worlds are becoming increasingly important in the exoplanet/astrobiology community. If plate tectonics create land masses, then can we say that a water-world (a planet with a global ocean and no ...
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What would change if our earth lacks mountains?

I just asked myself what is the role of the mountains on our planet earth? Well there's a well known role for the climate and weather. But is there a kind of physical or geological role? What would ...
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where are the thickest limestone layers on earth ? (CaCO3)

What is the maximum thickness of limestone layers on earth? (Limestone or any other biochemical sedimentary rocks, for example chalk or coral reefs.)
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Will another big earthquake hit Kathmandu?

Recently, we got the news that the western part of Nepal may be hit by a larger earthquake than that of April 25, because it did release all of its energy. During the earthquake, only the eastern part ...
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Is there a reason most mountain ranges seem to run parallel to coastlines?

Eyeballing a map of the world, it seems that most mountain ranges that don't occur along continental fault lines run parallel to coastlines. Is there a reason for this?