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.
221
questions
1
vote
0
answers
6
views
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 ...
2
votes
1
answer
36
views
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 ...
- 121
3
votes
0
answers
22
views
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 ...
2
votes
1
answer
43
views
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 ...
4
votes
2
answers
44
views
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 ...
- 41
8
votes
1
answer
291
views
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 ...
user27902
7
votes
2
answers
5k
views
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 ...
- 189
1
vote
0
answers
22
views
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 ...
- 131
4
votes
1
answer
69
views
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 ...
- 141
3
votes
2
answers
75
views
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.
...
- 33
5
votes
2
answers
217
views
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 ...
- 51
1
vote
0
answers
25
views
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 ...
- 51
7
votes
4
answers
4k
views
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; ...
- 173
3
votes
1
answer
486
views
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 ...
- 261
2
votes
2
answers
250
views
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 ...
- 141
5
votes
0
answers
63
views
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?
- 341
3
votes
2
answers
81
views
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/...
- 341
3
votes
0
answers
49
views
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 ...
- 341
13
votes
3
answers
2k
views
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 ...
- 341
5
votes
2
answers
385
views
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 ...
- 275
5
votes
0
answers
42
views
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 ...
- 51
14
votes
1
answer
1k
views
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 ...
- 1,187
2
votes
1
answer
123
views
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 ...
- 21
2
votes
1
answer
138
views
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 ...
- 121
3
votes
2
answers
172
views
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 ...
- 705
4
votes
0
answers
59
views
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 ...
- 251
5
votes
1
answer
530
views
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 ...
- 51
3
votes
1
answer
127
views
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 ...
user22279
5
votes
0
answers
181
views
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-...
- 705
4
votes
1
answer
1k
views
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 ...
- 554
4
votes
0
answers
55
views
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 ...
- 141
2
votes
1
answer
164
views
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 ...
- 475
0
votes
1
answer
53
views
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 ...
- 101
1
vote
2
answers
225
views
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?
- 113
1
vote
1
answer
131
views
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 ...
- 241
0
votes
1
answer
85
views
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.
- 25
1
vote
4
answers
644
views
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 ...
- 159
2
votes
1
answer
134
views
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 ...
3
votes
0
answers
58
views
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 ...
1
vote
0
answers
75
views
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? ...
1
vote
0
answers
22
views
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 ...
- 335
3
votes
2
answers
169
views
Why aren't there ultra acid igneous rocks?
In my study, I found that in volcanoes when the magma is going up it formed different types of rocks. There are basic, acidic and ultrabasic.
My question is why isn't there ultra acid igneous rocks ...
- 31
1
vote
0
answers
53
views
Why is Europe still considered a continent(along with Asia)? [closed]
It is true that there are multiple definitions of a continent. But it is also true that Europe fails to satisfy any of them. One of the boundaries between Europe and Asia was chose arbitrarily(the ...
- 153
3
votes
1
answer
1k
views
What was the Earth's continent's positions 10000 years ago, or 11700 years ago, AKA when the late Pleistocene epoch was coming to an end?
In many articles online, geologists and geographers have described and depicted the theorized locations of all our continental plates with great detail and illustration, providing pictures, time-lapse ...
- 33
4
votes
2
answers
356
views
Why aren't the Hawaiian islands a continuous strip of land?
My understanding is that the Hawaiian islands were produced as the Pacific plate moved over a stationary hot spot, which sent magma burning up through the plate as it passed over, forming a trail of ...
- 199
4
votes
2
answers
999
views
What sort of a plate is the Sunda plate?
I have read that the islands of Sumatra & Java have resulted from the subduction of oceanic crust of the Indo-Australian plate beneath the Sunda plate. I want to know whether this boundary is ...
- 381
2
votes
1
answer
98
views
Amount of Distortion at Continental Collisions
Something that I've wondered for a while now - When continents collide, how much of the landmass gets distorted by the collision before it settles?
To perhaps give a clearer idea of what I'm talking ...
- 241
3
votes
0
answers
91
views
Where and how big was Sicily between 5 and 1 Ma ago?
Sicily is a geologically complex island which seems to have been extensively studied geologically and from a tectonically point of view. There are an overwhelming number of papers dealing with the ...
- 31
5
votes
2
answers
549
views
Why isn't Iberia a tectonic plate?
I usually read that Iberia is a subplate, while India is a plate.
But it was a plate at the beginning of the Alpine Orogeny:
Source: wikimedia.org
Description: Tectonic map of southern ...
user18590
4
votes
0
answers
49
views
How long for tectonic plates to develop from a planetary, molten planetary surface?
On Earth or an Earth-like planet, how long does it take for a molten surface to solidify into planetary crust, and how long does it take for that crust to develop into tectonic plates?
- 141