10
votes
How accurate is the law of superposition?
The principle does not apply to all materials on earth as observed by us but is primarily concerned with sediments and rocks that form from sediments. Since sedimentation is a process driven by ...
- 5,014
7
votes
Accepted
Does iron in core have chance to come out to crust?
No, we occasionally get fragments of upper mantle overthrust onto the Earth's crust, but then the specific gravity (density) contrast is not so great, roughly 2.7 to 3.0 for crust, about 3.2 for ...
- 14.2k
7
votes
What is the average temperature of the whole planet Earth, not just the surface?
TL;DR:
Approximately $2700\,\text K$ ($2400\text{°C}$, $4400\text{°F}$)
Assuming that the weights are indeed the heat capacity per unit volume $C$ and that $C \approx \rho C_P$, where $\rho$ is the ...
- 241
6
votes
Accepted
Do these rock layers correspond to different years?
To me it looks like a mylonite, a type of metamorphic rock formed by intense ductile deformation. This deformation breaks the original minerals, which then recrystallize as small grains along the ...
- 7,729
6
votes
How accurate is the law of superposition?
Here is another example where the law of superposition breaks. Mind you this is a natural process: meteorite impacts.
A meteorite impact will excavate material from the bottom, and deposit it above ...
- 23.1k
5
votes
Do Earth's layers move at different speeds?
The inner core rotates slightly faster than the rest of the planet. This passage from National Geographic explains:
The liquid outer core separates the inner core from the rest of the Earth, and ...
- 2,177
5
votes
How accurate is the law of superposition?
As Peter correctly responds, for sedimentary rocks the principle of superposition is pretty much watertight except where tectonic superposition takes place. The latter can either repeat the ...
- 14.2k
5
votes
From how deep in the mantle has any rock ever been brought to the surface? Have scientists found anything they believe originated in the outer core?
Diamond is stable at high temperatures only under very high pressures. Mineral inclusions in a diamond, and the rocks in which a diamond are embedded, can offer further clues as to the depth from ...
- 161
4
votes
From how deep in the mantle has any rock ever been brought to the surface? Have scientists found anything they believe originated in the outer core?
As far as I know the best estimate is "upper mantle" from mantle xenoliths but that's not terribly specific. I am not sure if knowing more than that is possible right now.
- 41
4
votes
Accepted
How does Vertical Electrical Sounding Work?
The diagram is perhaps a little mis-leading.
Think of the ground/rock between the electrodes as a big resistor. The surrounding rock can be modeled as a set of parallel resistors. Most of the ...
- 3,903
4
votes
Accepted
Do Earth's layers move at different speeds?
Im am currently doing my masters in geophysics (last semester) and before that I did a bachelor in geoscience.
I assume by layers you mean the crust, the mantle and the core.
These all have ...
- 56
3
votes
Accepted
What produces these amazing 3D structures in Tibet?
The terrain examples show some striking similarities to what is referred to in the United States as "Badlands" - a type of terrain formed by layered sedimentary strata of rock that is soft enough to ...
- 1,144
3
votes
How is geological time divided into units?
The divisions in the geologic time scale have evolved over time.
Its origins can be traced back to Nicolaus Steno in 1669 described two basic geologic principles.
The first stated that sedimentary ...
- 5,959
2
votes
Oldest to Newest Bedrock in the USA "road trip"
If you were hoping for a smooth succession from Archean all the way down to Quaternary, you're going to be disappointed. Geology is messier than rocks being serenely laid down continuously through ...
- 3,548
2
votes
Is There a Correlation Between Earthquake Magnitude and the Deformation Observed in the Rock?
Generalizing such relationships is, as suggested above, hard to impossible - but for well studied and understood systems such correlations have been observed. For instance there is a clear, and almost ...
- 2,010
1
vote
Is There a Correlation Between Earthquake Magnitude and the Deformation Observed in the Rock?
You are probably thinking of pseudotachylite veins, which are interpreted as "fossil earthquakes" (among other things). To my knowledge, the first who tried to quantify some seismic ...
- 7,729
1
vote
Is There a Correlation Between Earthquake Magnitude and the Deformation Observed in the Rock?
There is no mathematical equation relating geological deformation with earthquake magnitude.
Different faults move differently. Some move horizontally (strike-slip faults). Other move vertically (...
- 24.6k
1
vote
Why were the Interglacial periods in the early Pleistocene spaced about one million years apart, but recent ones only 100,000 years apart?
It was a transition from a 41000 year cycle to a 100000 year cycle that happened about a million years ago (the Mid-Pleistocene Transition), not from a 1000000 year cycle to a 100000 year cycle. There ...
- 23.1k
1
vote
How to prove that there is no life undergound?
The Kola Superdeep Borehole is 12.2 Kilometers. At the bottom of the Kola Superdeep Borehole it gets pretty hot, and there is no soil or much organic matter since it would probably have turned into ...
- 574
1
vote
Is There a Correlation Between Earthquake Magnitude and the Deformation Observed in the Rock?
Surface Displacement vs. Earthquake Magntidue
This answer presumes that you are looking for a relationship between earthquake displacement and earthquake magnitude. I think what you are looking for ...
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