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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What is the maximum intensity with which an earthquake can struck Chitral city in Northern Pakistan?
I am working on a disaster response logistics case study in which I am using Mi-17 helicopters for transportation of relief to the affected areas in main Chitral city.
In this regard, I want to ...
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Is the Pacific Plate composed of smaller plates?
The question, Why are all lower mantle plumes under oceans? has the following diagram
which was taken from Wikipedia Commons.
About half of the large red dots occur on or near the boundaries of ...
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Is it inaccurate to describe Earth's mantle as "soft and plastic"?
The Earth's mantle, away from the occasional magma chamber, is solid. But it flows over time and so is described as "pliant", "hot chocolate", "toothpaste", etc.
Glaciers ...
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Do subducted continents rise up again through ridges?
Layman here, sorry if this is a stupid question. I have a geology friend who recently told me that plate tectonics is like how warm milk cools on top to form thin solid layers. The convection cells in ...
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If among oceanic crusts older means heavier, then why is old continental crust lighter than new oceanic crusts?
When we consider two oceanic crusts, the older oceanic crust is heavier and the newer oceanic crust is lighter.
But when we consider two crusts, one continental and the other oceanic, continental ...
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Is the earth crust under the pacific ocean heavier than in the rest of the planet?
Please bear with me, since I don't know much about geography or geology.
I was looking at an earth globe and noticed the pacific ocean covers virtually half of the planet (more or less). How is it ...
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Why is basalt denser than granite?
If lava is nothing but magma breaking through the earth's surface, then why is basalt more dense than granite?
I understand that something happens during the cooling process, but cannot find any ...
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Do these rock layers correspond to different years?
This is a close picture of a cliff in the north coast of Spain. As you can see, the rock is composed of multiple thin layers, alternating between dark and light materials. Could this be the result of ...
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Do tidal forces affect subduction?
I know subduction in plate tectonics is mainly density driven.
Probably a hypothetical question, but can weaknesses caused by tidal forces have an influence on the start of a subduction zone? Would ...
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Is the Theia impact partly responsible for the distribution of mantle plumes?
I was looking at a map of the distribution of mantle plumes, and was wondering if they could be residual material that was either brought here or affected by the Theia impact.
It seems to me that this ...
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Can a tectonic plate subduct under one plate while another plate subducts under it along the same boundary?
At a triple junction plate boundary there are three tectonic plates meeting. We have plenty of examples of these boundaries on Earth, notably the Afar Triple Junction, Mendocino Triple Junction, and ...
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Google Earth type, online plate-techtonics demonstration over time
I once found an site on the internet that displayed the continents in a Google Earth type setting where you could spin, zoom and navigate around the Earth but in different geological time periods. You ...
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Speculative Plate Techtonics - Resolving intersecting subductions
I'm working through Artifaxian's (https://www.youtube.com/watch?v=AzD_WVsEIRM) series on using gPlates to make tectonic history. I've run into the place where I have two subduction ridges about to ...
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What forces plays the role in order to subduct the denser tectonic plate under the lighter plate?
I am a 10th grade student and I don't know much about geology but I'm learning about subduction online. It's always mentioned that the denser plate gets subducted under the lesser denser plate. I want ...
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Does the Moon affect earthquakes?
Does the Moon, through factors like its location (if it is at an apsis i.e closest point or furthest point in its orbit) or some changes in density, affect earthquakes on the Earth?
Earthquakes are a ...
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Would the US East Coast rise if everyone living there moved away?
I watched a documentary about research on the coasts of Greenland where the sea level has fallen. According to the research, this is because a lot of the glaciers have melted, resulting in less weight ...
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Least equatorial ( and tidal) bulge consistent with modest amounts of water in polar regions
In World Building I asked a question about the climate of an hypothetical planet.
There Vogon poet said that
Everyone above 10° latitude will be in permanent drought
Considering that there were no ...
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Origin of the continents
Visiting from WorldBuilding SE. Someone recently asked a question that dusted off an old theory I had once had, so I started digging. Sadly I could find little more on the topic than the first time I ...
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Why are the supposed-to-be results of collision and/or subduction formed in an area where collision and/or subduction didn't happen?
Please correct me if I have said something wrong, as it might be the answer to my question. Also, these are all the things that I've learned through self-studying, so I might have been mislead.
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How is felsic magma produced at island arcs?
I previously believed that continental crust owes its lower density to the partial melting of oceanic crust; the mantle would partially melt at mid-ocean ridges to produce basaltic crust, and when ...
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Would obliquity and precessional changes of Earth affect the accuracy of GPS-based measurement of tectonic movements?
The rate and direction of tectonic movements can be measured by comparing the coordinates of the same GPS receiver over time. The coordinates are obtained using trilateration.
All materials I could ...
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Does the Plate tectonics contradict the theory of continental drift?
According to the theory of continental drift, South America and Africa was so closed to each other that the convex triangle of South America meets the concave hollow of Africa.
Source: usgs.gov; ...
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Is there any research on the relation of asteroid impacts and hot-spots?
In a new video by Atlas Pro on Hawaii linked below, he indicates a curious observation: Most hotspots antipode’s have sign’s of heavy impacts from asteroids.
He postulated that the force of these ...
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Are oceanic plates or continental plates heavier?
If you take a cilindrical section with radius 1 meter of both kinds of plate, which will have a larger mass?
My guess is that continental plates are heavier than oceanic plates, because they are more ...
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What is causing the crustal extension exhibited by the Basin and Range province in western North America?
Is there any link with the subduction of the Farallon Plate and the associated spreading center?
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Can continental plates collide and fuse together without an orogenic band or magmatic arc or at the junction?
I have seen this diagram on Wikipedia (link below). It shows that some North American mini-plate boundaries are orogenic bands and some are magmatic arcs, and I think those correspond to continent/...
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Why is the Colorado Plateau so stable?
The Colorado Plateau somehow has avoided all the tectonic activity around it over hundreds of millions of years. Is it just luck, or is there something about that chunk of crust? I have toured the ...
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Why are there no volcanoes where continents collide with each other?
I understand that volcanoes occur where oceanic crust is subducted under continental crust such as the Andes. However, they don't occur at places like the Himalayas and Alps where continental crust is ...
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How likely are caverns inside the mantle?
Almost everyone wrongly assumes that the Earth's mantle is liquid, but it isn't (only the outer core is). Is it possible then that there are hollow spaces within the mantle, similar to caves in the ...
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Difference between Ocean-Ocean subduction and Continental-Ocean from earthquake data
I am having a hard time finding this anywhere -- if no one can answer, I would appreciate a reference.
I was doing introductory homework in earth science, and we had to determine the kind of plate ...
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Is there a geological explanation for the recent Mammoth tusk discovery 185 miles off the California coast?
A recently publicized discovery of a Columbian Mammoth tusk located well of the coast of California in quite deep water made me wonder if geological conditions 100,000 years ago can explain how it got ...
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What role does the hydrosphere play in tectonic plate convection?
I need to do a "how do different 'Earth's spheres' interact with each other" and I'm trying to figure out how the hydrosphere would affect the lithosphere if the ozone layer were to ...
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Tectonic plates terminology
I have a very basic doubt regarding what the tectonic plates mean. In Wiki article Subduction is defined as:
Subduction is a geological process in which the oceanic lithosphere is recycled into the ...
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When did the proto-Himalayas become non-volcanic?
In the normal course of events, when continents move toward each other, at least one coast will be associated with a subduction zone and corresponding volcanic activity. When the Indian subcontinent ...
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Is there any source that shows all of Earth's terrain changes from Pangea to present?
I teach a class on my state's history to middle school students. Our textbooks do not cover much historical geology, but its a subject students are fascinated in, and feel needs to be added.
I want to ...
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Why does the ocean floor look so scratchy?
Why does some part of the ocean floor look so scratchy?
If you look at Google Earth image of the Indian ocean floor, especially the area south-west of Sumatra, it looks like some cosmic beast ...
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Slab-breakoff - always connected to continent/continent collision?
The question came to me when pondering the Andes:
Is a slab-breakoff always connected to the transition from subduction of oceanic crust to a continent/continent collision?
Current understanding is ...
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How do the Andes get so high?
I'm interested in the limiting factors on the height of mountains. There is a very good explanation at https://www.quora.com/How-tall-can-a-mountain-become-on-Earth-Neil-deGrasse-Tyson-says-Mount-...
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What will happen to the Indian plate after it slides under the Eurasian Plate?
What will happen if the Indian Plate is done sliding under the Eurasian plate? I hypothesied some possible answers. Tell me the answer and if my hypothesis is not correct.
Most likely to least.
It ...
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Farallon plate subducting under North American plate: is it a factor in "the next big one"?
I am a writer, not a scientist of any kind. I live in the SW AZ desert (USA), so we get earthquakes from time to time. I grew up in southern CA, right next to the San Andreas fault, so I have a ...
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How many supercontinents have there been? [duplicate]
With plate tectonics, supercontinents split up into smaller continents, and then the smaller continents get mashed up together to form a new supercontinent. There used to be a single supercontinent ...
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How on "Earth" can you make all those measurements of Earth forming?
This question is a result of recent news that Earth had a "boring billion" years in which mountains ceased to grow, and subsequently hindered life evolution.
The article went on to give ...
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Why are there no subduction trenches on continental land?
The ocean has some of the deepest locations on earth, typically caused by subduction zones. Why are there no subduction trenches on land?
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What happens when a mid-ocean ridge sub-ducts underneath continental crust?
I'm aware that oceanic crust always sub-ducts to continental crust, but surely the geologic forces pushing the ridge apart in the first place isn't just going to turn off, right?
Any answers would be ...
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Is COMSOL Multiphysics good for subduction CFD modelling? Are there alternatives?
As a beginner for CFD modelling of plate subduction, I heard comsol to be a good software. Can anybody suggests alternatives and the demerits of using COMSOL Multiphysics? Thank you.
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Can garbage be sent into the (near-)center of the world?
I've been thinking about how difficult it is to eliminate toxic chemical waste -- it usually needs high temperatures and pressures. So: would it be feasible (and maybe cheaper) to send it into the ...
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Will California become a subduction zone in the distant future
California is one of the few places in the world that lie on a transform fault. My question is why considering the fact that North American Plate is moving westward shouldn't California be a ...
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Is it possible for Mexico to have a magnitude 9 earthquake?
Everyone has heard of the Cascadia Subduction Zone and the potential threat it poses. However, I have heard nothing about The Cocos Subduction Zone, even though it caused a devastating earthquake over ...
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Nickel question - non geologist me
Why are there no giant nickel porphyry deposits like those of copper, or SEDEX deposits, like those of zinc? Why is all the nickel found in direct magmatic intrusions from the mantle to the surface? ...
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Seismic activity in the UK [duplicate]
On 8th September 2020 there was a magnitude 3.9 earthquake here in the UK at 51.817°N 0.665°W which is approx. 10km/6.2miles east of Aylesbury or roughly 50km/31miles east of Oxford.
This got me ...
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