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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Has a heavier atmosphere and the relocation of oil around the Earth had a measurable effect on the rotation of the Earth?
I am wondering if the creation of man-made carbon emissions in the Earth's atmosphere over the past 100+ years, and also the relocation of oil around the Earth over this same time period, has had any ...
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Where can I find an anisotropic PREM-like model for Earth's interior?
So, I just discovered PREM (the Preliminary reference Earth model) which models the density distribution of matter inside the Earth to any depth.
The PREM is very convenient but since it only depends ...
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What is the reason behind the density being negative value
This is the example density depth functions for various sedimentary sections world wide. But someof the sections marked with red, due to their last term, as i increase the value of z(depth) they ...
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What criteria determines whether earthquakes are classified as new or aftershocks?
I saw a recent paper where it is claimed that aftershocks can occur years, decades or centuries after the main earthquake.
When seismic activity is observed, what criteria determines the ...
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Input of the relation, source and receptor files into SLB Omega
Is anyone using SLB Omega that knows how to input the source, relation and receptor files that are not using SPS format?
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Composition of Earth's Core
Is there a list giving an estimate of the abundance of every element of the periodic table in the Earth's Core - possibly differentiating by inner core and outer core?
I am specifically interested in ...
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How to extend the Wyllie time average equation to multiple constituents
I understand the Wyllie time average equation
How to extend it to multiple constituents ?
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How bad is geo-engineering?
It is just curiosity that forced me to ask this question. At some point in time, if we can't control global $\sf{CO_2}$ emissions, temperature will increase until a tipping point and it will be a ...
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How to compare sensitivity with lithology between different crossplots?
In the given figure, which is plot of various elastic parameter for sand (blue) and shale(red) sequence. How to find Which crossplot has has greater sensitivity to lithology? Also what is mean by ...
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What is technically wrong with Wijngaarden & Happer's paper claiming to show that CO2's contribution to surface warming is saturated?
The paper, Dependence of Earth’s Thermal Radiation on Five Most
Abundant Greenhouse Gases1, has been reportedly rejected from several major journals. By analysing absorption spectra of greenhouse ...
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Why is static modulus greater then dynamic modulus in limestone?
Generally dynamic modulus is greater then static modulus and experimental data matches that. But in chalcedonic limestone, the static modulus looks to be greater than the dynamic modulus. What could ...
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What is the reason that some elastic constants are negative?
In this table of elastic constants, indices m = 1 and n = 4 result in negative values. What could the reason be?
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what is the value of y in additive time series decomposition
I understand the additive time series formula is y = trend + Seasonal + cyclic + residual. But what is the value of y. Is it the the combination of trend, seasonal , cyclic and residual which is shown ...
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How to connect drillhole from section to the planar view to calculate dip and azimuth?
We have a set of old sections with drill data that I would like to extract and model. I can add sections just fine in Leapfrog, but I have issues with the drill holes, especially connecting the drill ...
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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?
I wonder if this is even possible to know....
Do geophysicists and geologists have even a 'theoretical' idea about how deep Earth's churning of its layers goes?
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How probable is it that Earth's magnetic field will change 180 degrees at once?
Today the Earth's magnetic field is moving a little bit, but is there going to be a point where the field suddenly radically changes direction? If so, what will be the cause of that? If not, then is ...
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How is the apparent volume affected by particle packing?
This is from paper "The packing of particles" by A.E.R Westman and H.R. Hugill.
Here they give result as, "it is evident that if the diameter ratio is
unity, ie., the coarse and fine ...
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Identifying continuously-recording seismic stations
I am trying to identify which stations within the NCEDC network are continuously recording ground motion, and which record only intermittently. I am using obspy's ...
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I am trying to write a simple python script for dispersion analysis of surface waves, but I think I am missing something conceptually
I have some simple seismic traces as shown here.
When attempting to perform a dispersion analysis using the technique described by this paper, I get the following image.
Unfortunately, I cannot for ...
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Is the global temperature of the earth a physical quantity at all?
In discussions with physically educated among the deniers of the greenhouse effect, it is repeatedly claimed that it is completely pointless to state a quantity such as a global average temperature 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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Do gravity and magnetic field change along a geographic latitude or not?
Along the same geographic latitude does magnetic field change or not, and the same for the gravitational field, does it change along a geographic latitude? Please explain.
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Necessary Altitude to See Curvature of the Horizon [duplicate]
Many people have asked how high above the earth one must be to see the horizon curve, but I have yet to see a mathematical answer that correlates to the dimensions of the earth. As you rise above the ...
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How to quickly or easily prove the world is spherical?
A relative of mine has recently introduced me to the modern flat earth theory, which she believes in. Setting aside for the moment that it is ridiculous, and that sending up some balloons with cameras ...
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What is a general formula for Earth gravity as a function of radius, given a spherical shell model?
I'm trying to derive the formula for gravitational acceleration as a function of Earth radius $g(r)$, given a spherical shell model where each shell has a constant density $\rho(r)$. If I set $r=0$ to ...
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How do Rossby Waves in the ocean form?
So on land, I believe that one factor in their formation is due to inhomogeneities in surface heating between land and ocean (and also inhomogeneities in surface heating due to terrain effects like ...
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Where can I get Carbon Capture Storage data?
I need CCS data for Carbon Injection monitoring for a seismic hazard study. Is there any open source data that related Carbon Injection monitoring for example seismic, wells, 1/2/3/4D seismic and etc.
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Did the 1990 Manjil-Rudbar earthquake postpone a massive earthquake in Tehran?
In this site (published on 6 November 2001) I found the following information:
Historical data suggest there is a major earthquake in Tehran every 158 years and the last one there was in 1830.
The ...
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How to calculate latitude and longitude based on relative distance
The coordinates of A on Mars are 125°E and 25°N. The distance of point B is x meters due east from A and y meters due north from A. How to calculate the latitude and longitude of B. Please try to use ...
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Conditions at the bottom of a VERY deep hole
I'm a science fiction author looking to describe what conditions might be like at the bottom of a cylindrical shaft ~ 30 meters across and ~ 35 km deep. It's located somewhere on the edge of ...
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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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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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Impact Erosion Selectivity In Offloading Radioactive Material
ref : https://science.ubc.ca/news/asteroid-impact-erosion-helped-make-earth-habitable
According to the theory of impact erosion, the early crust was presumably much hotter w/ radioactive isotopes (U &...
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Does the Coriolis Effect affect a wind from East to West?
I'm studying meteorology for a pilot license and there I was taught as a rule of thumb that wind at higher altitudes is approximately turned 30° clockwise to the wind on the surface due to the ...
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I got this error (segyread: format not SEGY standard (1, 2, 3, 5, or 8)) while converting from segy to su format on seismic unix
[ ~/Desktop/demo ] $ segyread tape=data.sgy| segyclean>data.su
segyread: format not SEGY standard (1, 2, 3, 5, or 8)
segyclean: fgettr.c: bad first header
[ ~/Desktop/demo ] $ 3200+0 records in
6+1 ...
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How fast does the Earth's inner-core spin?
How fast does the Earth's inner-core rotate compared to the Earth's daily rotation?
The inner core is always described as a spinning/rotating solid core while the Earth has a single revolution per ...
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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's the distance between the center of mass and geometrical center of Earth (CM-CF offset)?
I asked the same question on Physics StackExchange site. I now know that there are several types of "center" and I can tell, I'm interested in the CM-CF offset (CM = geocenter, CF = center of figure).
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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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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 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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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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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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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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Does the global temperature vary daily (hotter and colder days)?
Earth's current average global temperature (i.e. including hot deserts and cold polar caps) is reported be somewhere between 14°C and 16°C (depending on sources and methods).
This temperature varies ...
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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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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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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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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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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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