Questions tagged [geology]
The science comprising the study of the rocks Earth is composed of, and the processes by which they change. Some subfields of geology are petrology, mineralogy, and geophysics.
830
questions
2
votes
0
answers
36
views
Possibility of naturally cut diamonds
Is there a chance that diamonds may naturally occur as any of the geometric shapes in such a way that it is naturally brilliant and cut? Obviously, I am not expecting really sophisticated cuts but ...
- 121
1
vote
0
answers
9
views
hi, any ideas how to convert Rcd and Dst seismic data into SEGY?
any ideas how to convert Rcd and Dst seismic data into SEGY?
- 11
1
vote
1
answer
53
views
How do these holes form?
I was casually browsing the google earth street view map today. And I noticed strange cavities in a rock wall on Henderson Island, a coral island in the South Pacific. What could have caused this to ...
- 111
1
vote
1
answer
40
views
How does the caprock of aeolian landforms such as mesas, buttes and hoodoos protect the underlying soft rock?
Why do we see a bipartite cliff,i.e., a vertical top portion and a slanted bottom portion at the edge of a mesa or butte? I came to know from the internet that the top portion is the hard caprock And ...
3
votes
1
answer
170
views
The total pressure / total mass of earth's atmosphere on geological time scales
In many introductory geology courses, a great deal of time is spent on the historical composition of earth's atmosphere: the great oxygenation event, oxygen maximum during the carboniferous, ups and ...
- 173
1
vote
0
answers
23
views
What rock layer is beneath the Vishnu Basement Rock in the Grand Canyon?
I read that the deepest part of the Grand Canyon that we can see are the Vishnu Basement Rocks, deposited 2 billion years ago (according to the Grand Canyon Wikipedia page). But what kind of rock lies ...
- 11
4
votes
1
answer
87
views
Likely air composition in cave only accessible from underwater?
I recently stumbled on the images of the Cosquer cave, located in France, famous for being a comparatively recently discovered as a Paleolithic decorated cave.
The entrance to cave now is more than ...
- 143
1
vote
0
answers
38
views
What happens to seismic waves reflected back to the surface?
What would be the behavior of seismic waves when it hit the geological media?
The waves coming from a source hits different boundaries with different energies, the wave will be reduced in energy by ...
- 11
1
vote
0
answers
28
views
How fast and big would the waves be in the rocks from the Richter scale 10 earthquake at Chixulub
If I was near Australia and China when the 10km meteorite hit Chixulub 65 million years ago, the first thing I would have noticed is an earthquake high above magnitude 9, and the ground would shake by ...
- 1,349
1
vote
0
answers
69
views
How do geologists examine mountains and hills inwardly?
There is an idyllic verdant valley where I live, full of mountains and hills. Most mountains are covered by vegetation, but some have flat steppe-like tops where people have small farms and homesteads....
- 11
0
votes
0
answers
5
views
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?
5
votes
3
answers
225
views
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 ...
- 211
0
votes
0
answers
26
views
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 ?
- 39
1
vote
0
answers
21
views
Good modern paper demonstrating differentiation of glauconite and berthierine using xrd or FTIR
I'm looking for a recent paper that demonstrates how one would unambiguously differentiate glauconite from berthierine and have yet to find something useful.
I'm running across a lot of papers seeming ...
- 11
1
vote
1
answer
73
views
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 ...
- 111
2
votes
0
answers
29
views
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 ...
- 111
2
votes
0
answers
31
views
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 ...
- 111
1
vote
0
answers
36
views
How much of the planet's land mass is between the Tropic of Cancer and Tropic of Capricorn [closed]
I know this isn't readily available. I know that it is 68% Northern Hemisphere vs 32% Southern. And I know that it's 68% Eastern vs 32% Western.
My wife asked me why I wanted to know and she got the ...
- 11
3
votes
1
answer
133
views
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?
- 111
1
vote
0
answers
100
views
Is the Pacific Plate composed of smaller plates?
The question, Why are all lower mantle plumes under oceans? has the following diagram
which was taken from Wikipedia Commons.
About half of the large red dots occur on or near the boundaries of ...
- 24.7k
2
votes
0
answers
37
views
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 ...
- 111
0
votes
1
answer
148
views
Why the groundwater depth is different in same area
I recently measured groundwater levels using a tape in three different boreholes for where the holes are in same area. Each hole had a different level of water. Holes A and B are just 4 meters apart ...
- 39
1
vote
1
answer
79
views
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 ...
- 133
2
votes
1
answer
109
views
Why are all lower mantle plumes under oceans?
Having a look at the attached image (original at Wikipedia Hot Spot page) I noticed that all mantle plumes originating from lower mantle (in red) are under oceans. Why?
- 261
1
vote
0
answers
50
views
Estimation of rare earth elements in the SUAC complex
I am currently competing in a case study competition a part of which has asked us to estimate the amount of Nd, Pr, and Dy in the SUAC complex (Sung Valley Ultramafic-Alkaline-Carbonatite) in electric ...
- 11
3
votes
1
answer
115
views
Pre-Phanerozoic CO2 levels and pluricell life influence in C Earth's cycle
This graph presents an estimate of Phanerozoic CO2 levels on Earth.
From the onset of the graph, it appears that CO2 levels are rising. However, I've come across papers, such as this one, suggesting ...
user29779
11
votes
2
answers
3k
views
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?
- 795
3
votes
2
answers
111
views
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 ...
- 39
3
votes
1
answer
439
views
Do subducted continents rise up again through ridges?
Layman here, sorry if this is a stupid question. I have a geology friend who recently told me that plate tectonics is like how warm milk cools on top to form thin solid layers. The convection cells in ...
- 133
0
votes
0
answers
60
views
Are These Leaf Fossils Found Near a Texas Lake Shore?
I recently came across some intriguing specimens near a lake shore in Texas and am seeking your expertise to help identify them. The objects have a few characteristics that lead me to believe they ...
- 23
1
vote
1
answer
214
views
How fast can water erode stone?
Is there a way to know, how fast can water erode stone? I mean, if I just put a single stone and drip water on it 24/7, how soon will erosion become noticable?
I've seen a video about "15,25 and ...
- 11
1
vote
0
answers
48
views
Why are most islands in the Caspian Sea elongated and some of them even have tails?
I was seeing the Caspian Sea from Google Maps satellite mode and I found most islands are elongated in shape (the biggest of them Ogurja ada or Ogurchinsky island).
Also there are islands that have ...
- 363
13
votes
1
answer
2k
views
Why is basalt denser than granite?
If lava is nothing but magma breaking through the earth's surface, then why is basalt more dense than granite?
I understand that something happens during the cooling process, but cannot find any ...
- 261
2
votes
0
answers
25
views
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.
- 51
0
votes
1
answer
42
views
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 ...
- 363
2
votes
2
answers
136
views
How the small stones in this photo are created?
I need some help with my grandson's school homework: can someone describe what's the phenomena behind the creation of these small stones at the plateau´s foot? why & how are they created?
No big ...
1
vote
0
answers
61
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 ...
- 111
3
votes
0
answers
74
views
How was the Boesmansgat Cave in South Africa formed?
I found nearly nothing about this sinkhole online. Apparently the cave has water dating back thousands of years.
From where did this water come from. Is it just rain? And how dirty is the water now?
- 31
1
vote
0
answers
40
views
When was the thickness of the Earth's crust calculated?
When was the average thickness of the Earth's crust first calculated or estimated? What did scientists know about the thickness of the Earth's crust before the 20th century? In what interval(s) fell ...
- 111
2
votes
0
answers
24
views
Understanding the Facies and its Interpretation in Terms of Processes and Possible Depositional Environments
Fellow sedimentologists and geoscientists! I'm seeking your expertise in understanding a particular facies and its implications in terms of sedimentary processes and potential depositional ...
- 81
6
votes
1
answer
36
views
Suspended sediment yield
I am finding it difficult to understand the factors that affect the suspended sediment yield in an area. I was thinking of the Rouse number and how it is affected by the particle diameter, slope and ...
- 91
1
vote
1
answer
157
views
Mud cracks formation
Are mud cracks formed during rock formation or after the rock is completely formed?
- 11
1
vote
1
answer
128
views
How important or necessary are assumptions when it comes to radiometric dating?
So when I say radiometric dating, I'm specifically referring to U-Pb, Ar-K and Rb-SR rather than C14 as I think these are more accurate when it comes to corroborating an older earth. I've heard people ...
- 11
1
vote
1
answer
142
views
Map of earth subsurface temperature
I see similar flavours of this question have been asked a few times, but I still don't see a satisfying answer. I am looking for data (maps) of the earth subsurface temperature at a depth sufficient ...
- 272
1
vote
0
answers
89
views
How'd this hole get here?
Hiking in a field of boulders along a river canyon in Alabama United states. Sandstone boulders are 20'-30' (6 to 9 meters) tall. There are perfectly round holes near the top. I'm wondering what ...
- 11
1
vote
2
answers
156
views
Is there a theoretical maximum size limit for a rock?
There are many types of rocks: igneous rocks, sedimentary rocks, and metamorphic rocks. Some rocks are simply huge. Some of them are tiny. Is there a theoretical upper limit on the size of a rock, and ...
2
votes
1
answer
461
views
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 (...
3
votes
0
answers
26
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 ...
1
vote
0
answers
29
views
Hydrogeology Aquifer Question - Estimating Freshwater Availability
Bikini Atoll is at the northern end of the Ralik chain, and in a region that is somewhat drier. On average, the Atoll receives 1300 mm of rainfall each year, with the wettest season being from May ...
- 11
2
votes
0
answers
39
views
Copper shale in the Harz Mountains (Germany)
I wanted to ask if you have any suitable literature on copper slate (especially about the genesis) in the Harz Mountains. I was generally interested in how this copper shale differs from other copper ...
- 1,989