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Do normal modes of oscillation cause permanent deformation?
It is known that when a large earthquake occurs, say $M \ge 9.0$, The surface waves travel around Earth over and over, "ringing the surface like a bell". The GIF below is an example (Image Source):
Do these normal modes cause permanent deformation…
Neo
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What is the current theory about the formation of Tibet?
Although I basically understand, that how the Himalayas formed, it has always confused me how did the vast high Tibetian Plateau came into existence behind it? And what would be its future, is it expected to remain as such for a long time?
Sawarnik
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For what percentage of the earth's history has there been permanent ice?
Wikipedia comments here that "Permanent ice is actually a rare phenomenon in the history of the Earth, occurring only during the 20% of the time that the planet is under an icehouse effect." A "citation needed" tag is attached to this remark.
For…
user1205901 - Слава Україні
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Wind profile below the aerodynamic roughness length
The vertical profile of horizontal windspeed is often given by the so-called "log-law":
$$u(z)=(u^*/k)\ln(z/z_0),\ \mathrm{for}\ z>z_0,$$
which can be found here.
As can be seen from the equation, when $z=z_0$, $u(z)=0$. But what happens…
user4624937
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Is there a distinction between gap winds and channelled flow?
I have seen gap flows mentioned in the literature, for example [Gohm et al. 2004, Zängl 2002, Mayr et al. 2007]. Whiteman 2000 defines a gap as a "major erosional opening through mountain ranges" and states that a channel can occur "between…
hertzsprung
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What causes clouds to appear blue?
In a thunderstorm cloud about sunset time, I saw these clouds, including some (in the upper right) that were a unique shade of blue. I don't think I've seen clouds quite that color before. I tried to capture the color as best I could with a…
WBT
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When did the last rifting / break-up event occur?
When thinking about the formation of the current continents from a super-continent, it's clear that this is a gradual process, but there must be certain areas on earth which were once joined and were the "last" to break apart from Pangea.
Do we…
Nathaniel Bubis
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2 answers
Undersea riverbeds?
On a meandering bit of research through Wikipedia, I was looking at the
Google Maps location of Texas Tower 4.
South-east of that location there is what looks like a river valley under the ocean. If you follow it back to the land it is obviously…
DuncanKinnear
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How can I learn to spot fossils and fossil-bearing rocks on the Jurassic coast?
Due to a pleasant change in my circumstances, I have been to Lyme Regis several times recently, and it seems as though I'm going to be a regular visitor over the next few years.
As a former biologist I found the experience of combing the shore of…
Bob Tway
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Can climate change cause earthquakes, tsunamis, or volcanic eruptions?
Different scientists have brought forth a theory that climate change can cause earthquakes, tsunamis and volcanic eruptions. For example:
Professor Bill McGuire of University College London in his book Waking the Giant: How a changing climate…
THelper
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Should one extract wavelet from seismic or well log for the generation of synthetic traces?
Synthetics are generated by convolving reflectivity series with the known wavelet. I have seen most of the wavelet are extracted from seismic data itself. Is there any hard and fast rule, or can one extract wavelet from well log as well? If so which…
Kunal Rathod
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Using sodium chloride load as a point source pollutant variable in SWAT model?
I'm currently working with the Soil & Water Assessment Tool (SWAT). My task is to model the loading of sodium chloride into streams.
One approach I would like to take is to use the point source rechour.dat file command. The file can contain…
ITM
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What causes the different colours of the salt pits in the Saloum Delta in Senegal
What causes the different colours of the salts pits in the Saloum Delta in Senegal?
Fred
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2 answers
Change in earth mass since the time of the dinosaurs
Is there a significant difference in the mass of the Earth between now and the time of the dinosaurs (250 - 75 million years ago)? I was just wondering if the force of gravity on dinosaurs would have been significantly less when they were around.
I…
Brian M. Hunt
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Weak flashes of light in the sky
On a recent, late-evening flight from New York City to San Fransisco, I was seated on the right side of the plane. We were flying over lake Michigan - about 2 hours into the flight. When we were over the mid-west I looked out of the window and could…
TV Mohini
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