Questions tagged [geophysics]
Geophysics is a subject of natural science concerned with the physical processes and physical properties of the Earth and its surrounding space environment.
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Geotechnology: Prove a formula, calculated with unit weights, for void ratio
I don't know where else to post this.
I am reading a Geotechnical engineering textbook by B.M. Das, 6th edition.
Problem 3.1 is as follows:
For a given soil, show that
$$e=\frac{\gamma_{sat} - \...
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What is the relationship between earthquake risk, magnitude, and distance from the epicenter?
I need a (rough) functional relationship between these three quantities. My initial hypothesis is that the risk $R$ (intended as the probability of a building damage), scales with the square root of ...
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Does this support Hapgood's Earth Crust Displacement Theory?
I'm no Geologist by any standard but I'm quite intrigued by what goes on below our feet.
I came across this article that states there's a new or (confirmed) partially melted layer in the athenosphere (...
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Simple Mathematical Equation for the Geotherm
Hi I need a simple equation (polynomial third straight) for a PerpleX simulation to represent the mantle geotherm. The geotherms I have found on the internet so far (unfortunately I don't have the ...
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Where could I get waveform data on low-frequency earthquakes, very low-frequency earthquakes, volcanic tremor and non-volcanic earthquakes?
I am a marine geology masters student and I am writing my thesis on slow earthquakes. I will include graphs of the most common types of earthquakes:
Low-frequency earthquakes
Very low-frequency ...
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Is it possible that the rainbow sand dunes in Death Valley, California were formed by some massive mining in the ancient past? [closed]
I know there is a mainstream answer that thinks the rainbow sand dunes they be explained geologically... I just want to know if it's possible to form those colors and those dunes from mining? And if ...
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Why does calcium occur together with felsic rocks and magnesium with mafic rocks if calcium is denser than magnesium?
Felsic rocks contain a lot of sodium, potassium and calcium (and a great deal of aluminum), while mafic rocks consist of a lot of magnesium with iron....
Why is this?
Why is magnesium (z=12) in the ...
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How does the rotation of Earth's inner core influence climate?
In the recent paper published in Nature that sugests a 60-70 years inner core rotation cycle, it is said:
Interestingly, the same multidecadal periodicity is also well observed
in the Earth’s climate ...
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How much fresh water could be produced by pumping warm humid air through a pipeline up to the top of a mountain?
I have been doing a lot of research on the Internet lately about various desalination processes which are being used today and this led me to begin studying about mountain weather and the orographic ...
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Does the high pressure inside the Earth's core contribute to its high temperature?
The explanations for why the Earth's core is hot I found on the internet included:
leftover energy from the Earth's formation
radioactivity of the elements inside the core
friction between the core ...
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Relation between highlands and tidal forces
Could the presence of mountain ranges in continental areas near to tectonic plates boundaries prevent these plates from swaying up and down as a result of vertical tidal forces and plastic ...
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Where can I access public sonic well-log data?
I'm doing some research and I'm in need of some well-log data from a sonic tool. I'm specifically looking for a multi-receiver tool with 6 or more receivers if possible.
I've been able to find a lot ...
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What makes special a volcanic pipe to be stable until the mantle?
Comming from this question:
Can we really travel through earth's core?
I wonder what makes special a volcanic pipe to be stable since the mantle through the surface, in comparison to our try or ...
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Distribution of terrestrial impact craters
Recently I was looking at a map of known impact structures and I noticed that they are concentrated between the tropical and arctic latitudes, but there is very little near the equator. I can think ...
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Why were the Interglacial periods in the early Pleistocene spaced about one million years apart, but recent ones only 100,000 years apart?
The Teglen (or Tiglian) interglacial period began after approximately half a million years into the Pleistocene, and the next interglacial (Waalian) occurred about a million years after that.
But the ...
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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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Is there any free indexed journal that Geoscience students can publish?
I am planning to publish a paper related in Geoscience/Geophysics/Seismology within scope of Machine Learning/AI in particular. Is there any Journal that provide free article publishing for ...
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Under which conditions would you see the MOST lake effect precipitation?
It's well known that the Great Lakes produce large amounts of precipitation in the Fall. When cold polar air moves over the lakes it causes large amounts of relatively warm moist air to rise, ...
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Is it possible for tsunamis to occur on deep water planets?
Assume a water planet with an ocean depth of about 200-500 km.
Would a very strong ground-quake happening at the very bottom of the planet's ocean floor be able to cause a large tsunami to rise up to ...
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Why is some ocean on continental crust?
While most ocean crust is formed from oceanic plate formations there are areas of the ocean (much of the Gulf of Mexico, Eastern US coast, North Sea, Arabian coast of India) which appear to be ...
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Can a planet have both magma volcanoes and cryovolcanos?
I know that the Jovian ice moons have been speculated to have cryovolcanos. I was thinking of the ice planet of Hoth from Star Wars and in one of the video games; it has regular volcanic activity. ...
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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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Seismic velocity relations
I do understand why the seismic velocity decreases with temperature and increases with pressure, but I am not really familiar with the relationship between the velocity with Poisson's ratio. I ...
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What is the purpose of wavelet extraction from the seismic trace?
I would love to know what exactly we can do with the extracted wavelet. What kind of information extracted wavelet can contain?
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Can pumping water into the aquifiers reverse the sinking of cities like Jakarta?
Indonesia decided to relocate the capital, in part due to environmental struggles facing Jakarta:
one of the fastest sinking cities in the world due to the over extraction of groundwater
Source: ...
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What is a Poisson solid and what affect does it have on p and s waves?
What is a Poisson solid and what affect does it have on p and s waves?
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What are these undersea lines all around Hawaii?
On Google Earth, there are these radiating undersea lines all around Hawaii:
Here with a bit more contrast:
Unlike the other lines, they are pointed away (or toward) a single place.
What are these, ...
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Could a nuclear explosion in the Atlantic Ocean during the hurricane season trigger a hurricane?
I am wondering if denotating a nuclear bomb in the Atlantic Ocean during the hurricane season could trigger a hurricane.
For example, say that a 100-megaton bomb was loaded onto a ship and that ship ...
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On geostrophic wind. How can the Coriolis force cancel out the pressure gradient force when they are mutually perpendicular?
If we are in Northern Hemisphere and there is a point where there is a high pressure, denote it by H, and there is a point where there is low pressure, denote it by L, (for simplicity assume them to ...
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Ways of detecting underground bodies of water
I saw one way to achieve this using the magnetotelluric way, but I need some solid fundamental way to understand it. Any book recommendations would be appreciated.
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Airborne geophysical survey in steep and undulating terrain. What is more important, energy conservation or orienting lines wrt to geology and why?
I am trying to design a cost and energy efficient aerial survey and have come up against the question, 'do we have to fly straight lines perpenducular to geology?' as not doing so could make for a ...
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Is there a way to calculate crater depth?
For the sake of the example, let's assume a crater on Earth roughly twelve miles in diameter.
Is there a way to calculate a range between how deep or shallow this crater would be?
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Predicting rock type from seismic processing
In reflection seismology, we create a source with an airgun and then use receivers to register acoustic waves (an approximation) at the surface. From these measurements, we can predict a velocity ...
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Can "meanders in meanders" form naturally?
I recently rafted the San Juan river in Southern Utah, which flows into the Lake Powell reservoir. When the water levels in Lake Powell were very high, it extended far upstream into the San Juan ...
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Specific cases of 528 Hz harmonics that appear in nature that are not wideband radiation or noise? [closed]
I was looking up something about the 528 Hz frequency that people like to talk about, and some of the evidence used to support the idea seemed a little irrelevant. Like, of course the sun emits 528 Hz ...
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Taking into account the decay products of transuranic elements, are the world's uranium reserves growing or shrinking?
I was talking to a friend of mine who is an environmentalist like me but not a big fan of nuclear power and she told me it was not a good option in the long run because of the decay of uranium. Of ...
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Coriolis parameter approximations
When solving equations involving the Coriolis parameter $f = 2\Omega\sin{\varphi}$, I often see the $f$-plane (constant) or the $\beta$-plane (Taylor expansion) approximations.
If I'm solving ...
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Elevation accuracy to distinguish maximal gravity anomaly of a sphere with 50% hematite
Question: What is the accuracy required in elevation to distinguish the maximal gravity anomaly of a spherical 50% Haematite (Iron mineral) ore with a radius of <...
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Do greenhouse gases absorb and re-emit photons or reflect them diffusely? Or both? (CO2, CH4, H2O, N20, HFC-134a, etc.)
Also, would it matter if a particular type of greenhouse gas molecule reflected rather than absorbed and then re-emitted light? Would its GWP be higher or lower?
Perhaps this is more of a pure ...
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What are the boundary conditions for Navier's Equations of motion in seismic?
Navier's equations of motion in seismic have 3 solutions, according to how it is resolved (boundary conditions):
for Vp (compression waves)
for Vs (shear waves)
for Vr (Rayleigh waves)
I know the ...
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Can Hydrocarbons be beneficial? [duplicate]
Do these “fossil fuels” underground help maintain homeostasis in microbial ecosystem or aid in the growth of flora etc?
Or are these substances: coal, animal remains and natural gas detrimental even ...
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Range of frequencies of the Schumann resonance?
Crossposted at Physics SE
As the surface-ionospheric gap acts as a resonator for electromagnetic waves, it should have several harmonic values from the base, fundamental frequency of 7.83 Hz.
These ...
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How to interperet audio magnetotelluric results?
I'm newbie in filed of Geophysics science. I will be grateful if you could help me to understand this chart
what does line 12 or Line 11 mean? what about line15-14?
How to identify the depths?
what ...
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How long do geostrophic currents last?
My professor posed this question, without any relevant material. I suppose the currents last until the density gradient is neutralized, but I can't find any literature nor articles on this, regarding ...
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Understanding the EM survey results
I have contour maps showing conductivity and in-phase data from an electromagnetic survey done on a ground, where, supposedly, an underground sewer system is running horizontally across the survey ...
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What affects where a terrain will be rocky or grassy?
I’m working on a terrain generator and I now need to color the terrain to be rock, grass, or snow. Ignoring snow for now, at first I thought I’d make flatter areas grass and make steeper areas rock. ...
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What is the electrical conductivity of a liquid Komatiite?
I am searching for previous work that has determined the electrical conductivity range for komatiites at the surface. Does anyone have some values or references?
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How hot would days get if it were always the solstice in the northern hemisphere?
Imagine the Earth's axis of rotation were to precess in synch with the orbit of earth around the sun so the north pole always pointed towards the sun (same current axial tilt of about 23 degrees). ...
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What is the pressure at the center of the Earth?
In the question Does gravity increase the closer to the core you get?, it was determined that gravity reduces to zero at the center of the Earth. That is logical.
However if pressure is proportional ...
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Why should wellbores be supported by pressure, but not mine tunnels?
I recently read about safe mud window - it states that the mud pressure in a wellbore should be high enough to prevent well collapse, and should not exceed the formation's fracture pressure. But ...
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