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.
793
questions
7
votes
1
answer
165
views
Volcanic Explosivity Index of Cumbre Vieja eruption
I have been following the last events of Cumbre Vieja eruption since it started last month. Trying to grasp some basic knowledge of volcanology I have seen the eruption is classified as VEI-3 in the ...
- 73
7
votes
1
answer
441
views
The geology of local landscapes and small scale features
I'm learning geology to understand the processes behind the formation of my local landscape.
I understand the processes behind big features, such as mountains. But I'm struggling to understand the ...
- 782
7
votes
1
answer
64
views
Are trends in crossplots of compositional data from different analyses valid?
Some geochemistry papers that I have read contain crossplots of compositional components that resulted from different analyses of a rock sample. For example, one is the percent volume of TiO2 versus ...
- 71
7
votes
2
answers
214
views
Recreating the rock cycle
I want to recreate the rock cycle using some item that can behave as a rock. The purpose of this is to get a point across to my students about how really there is a reason why the rock cycle is called ...
- 1,952
7
votes
0
answers
167
views
How can we know the past height of mountains?
In Feynman Lectures on Physics Volume I, Feynman talks about the relation between Physics and Geology. He says “Mountains are no lower today, on the average, than they were in the past”.
Through what ...
7
votes
0
answers
96
views
Are there any known global effects of the Mediterranean sea evaporation and refilling?
This is a broad subject I realize, but I'm looking for specific geologically observed answers of global effects elsewhere, between about 5.96 and 5.33 million years ago when the Mediterranean sea was ...
- 5,777
7
votes
0
answers
76
views
High-resolution laterolog array tool
Does anybody know if it is necessary to apply corrections to the reading given by this logging tool? Corrections such as bed thickness, borehole diameter, invasion, etc.? If so, is there anywhere I ...
- 171
7
votes
0
answers
122
views
Did an impact crater cause the formation of the gas fields in north eastern South Australia
In the paper High Impact Reservoirs, the authors claim that impact craters have lead to both the creation and destruction of petroleum source rocks, reservoirs and traps.
Recently it was announced ...
- 23.2k
6
votes
3
answers
4k
views
What is the average color of soil?
Where I live the soil is red.
Is there a map or chart where you can see the average color of the dirt according to geographical location? What would the color be if all of the dirt on Earth was ...
- 1
6
votes
5
answers
342
views
Which Earth minerals would Moon colonists miss the most?
In my science-based novel, Moon colonists need to return to Earth to collect some rare or absent mineral(s) Ideally, something they could derive from seawater. Which minerals might they be...?
- 63
6
votes
3
answers
441
views
Simulating the earths crust
I would like to create a computer simulation which would fold two plane-ish surfaces into two crumpled-ish surfaces. This in order to simulate the earths crust movement and collisions resulting in ...
- 163
6
votes
2
answers
3k
views
What keeps water from sinking into earth?
I remember reading somewhere that there's evidence of water on Mars but it all sank into the Martian soil. So what prevents that happening on earth?
Some people say it's because the crust is not ...
- 161
6
votes
4
answers
239
views
Has there ever been a case where we have found what appears to be a prehistoric fossil but have no way of dating it?
I find that when ever I learn of a new fossil, the age of said fossil is always mentioned. This perplexes me given how intuitively rare it seems to have radioactive material to date a formation. I ...
- 169
6
votes
2
answers
196
views
What are these geological horizontal lines formed on this mountain called and why they are formed?
This images are of Mt. Kailash, Himalaya.
Front face of Mount:
Back face of Mount:
- 63
6
votes
2
answers
24k
views
At what depth does the underground begin to warm up?
Spring water comes out colder from being underground. But if you get deeper the temperature goes up. At what depth does the underground stop getting colder and begins getting warmer?
Is there a map ...
- 1
6
votes
1
answer
927
views
How can a non-geologist identify a rock? [closed]
I found a rock on a beach in north-east Evia, Greece. Half is light gray, and half is dark gray. There are white (or very light gray) thin lines that form swirls throughout, crossing the light/dark ...
- 179
6
votes
2
answers
255
views
Basalt sill - a contradiction in terms?
My textbook for a historical geography class mentions a couple of geological features it calls "basalt sills" (the sill of Rosh Pinah and one other).
I'm a total newbie to geology, but the ...
- 61
6
votes
6
answers
30k
views
Cause for round holes in stones
I picked up this stone form a beach on the south coast of England (lancing). How is it possible it has such round holes? Plenty of stones looked similar.
- 163
6
votes
2
answers
2k
views
Interpreting a geological map
I have a homework question that I'm stuck on, I have attempted interpreting this map but am not sure if I have to correct interpretation.
What is the youngest/oldest rock in the geological ...
- 185
6
votes
3
answers
520
views
Uranium Deposits in the Ocean?
I was wondering whether there are any uranium deposits in the ocean floor, or in the rock walls of the continental shelf, etc.
I was hoping to have some deep sea uranium deposits accessible from the ...
- 163
6
votes
2
answers
723
views
If I was to tunnel straight through a mountain, what kind of rock would I find?
I'm developing a semi-realistic game involving stereotypical dwarves digging into mountainsides and carving out grand caverns for themselves, similar to those in Moria or the Lonely Mountain from ...
6
votes
2
answers
8k
views
What kind of data is best shown in a rose diagram?
I am looking for some geological data where presenting it in a rose diagram is desirable. I don't really know what kind of data is suitable. Any suggestion of data — preferably from the field of ...
- 163
6
votes
2
answers
717
views
Why do ooids not grow larger than 0.5 mm?
I know ooids form in high energy water, by rolling and building layers around a nucleation site, but I don't understand what limits their size.
What keeps these such a regular, small size?
- 356
6
votes
1
answer
263
views
Do carbon dioxide hydrates exist in nature?
Do CO2 hydrates exist in nature? If so, how much carbon could they contain?
- 329
6
votes
1
answer
339
views
Geological evidence about climate change: has there ever been a period with a rate of climate change as great as it is today?
Most statistics about climate change are based on climate data over the last 150 year (as long as records have been kept). This seems irrelevant in terms of the geological time scale of temperature ...
- 63
6
votes
1
answer
3k
views
What separates the Karakoram Range, the Hindu Kush, and the Himalayan Range?
In Google Maps, I don't see any boundary between the Karakoram (a.k.a. Karakorum) Range, the Hindu Kush, and the Himalayan Range. What separates these ranges?
- 637
6
votes
1
answer
4k
views
How did the terms "acidic" and "basic" come to be associated with $SiO_2$ in igneous rocks?
Students of geology are introduced to in their petrology course, (or used to be), to the terms "acidic", "basic", and the associated term "intermediate" in relation to %$SiО_{2}$ in igneous rocks, ...
- 163
6
votes
2
answers
337
views
Is there a list of instances where mountains that have been mined out of existence?
Reading the Wikipedia entry for the Australian town of Broken Hill, I came across the following piece of trivia (emphasis mine):
The "broken hill" that gave its name to Broken Hill actually ...
- 63
6
votes
2
answers
344
views
Methods and Software for Interpolating/Modelling of Stratigraphic Well Data in 2D/3D
I have some geologic well data. The lithologies have been interpreted, and stratigraphic columns have been drawn. The columns have been adjusted for elevation, and correlation has been done between ...
6
votes
2
answers
746
views
Were all of Earth's minerals created before Earth's formation, during, or after?
I've heard that during the accretion of proto-planets that formed the earth, 60 minerals were created through the reactions of atoms and molecules in the nebula.
Do these first minerals still make up ...
- 782
6
votes
1
answer
226
views
Why do we measure eustatic sea-level from the center of earth?
Earth is rotating so it has a ellipsoidal shape. The measurement will therefore be different from equator and pole. So why do we measure eustatic sea-level from the center of earth?
- 61
6
votes
2
answers
275
views
Considering the thin piece of material on the surface of Mars in the image below, is there anything like it on Earth?
The above is a magnified part of the original image below captured by the Curiosity rover on Mars on sol 1729 (June 17, 2017).
From the added information with that raw image it can be estimated that ...
- 262
6
votes
2
answers
810
views
What was the likely composition of Earth's early crust (how did crustal composition evolve)?
Was the first crust entirely mafic (oceanic) crust which was later distilled via volcanic arcs along subduction zones to make felsic rocks or did the earth start with bits of felsic crust?
Are the ...
- 1,035
6
votes
1
answer
2k
views
Maps and Faults
I'm having trouble determining the type of fault represented on this map.
What type of fault is represented on this map?
What is the fault orientation?
What does this mean?, Do I do this by working ...
- 185
6
votes
1
answer
392
views
Hydrocarbon potential in Ganges Brahmaputra delta
According to Curray (1991):
Total sediment thickness beneath the [Ganges–Brahmaputra delta] southeast
of the hingezone exceeds 16 km...
Considering a normal geothermal gradient and data for oil ...
- 1,487
6
votes
1
answer
117
views
Would it be wise to monitor real time human activity to anticipate earthquakes?
Documented strange behaviors of animals before an earthquake could invite us to believe that some of them anticipate tectonic activity. We also know that human complex organization makes it difficult ...
- 161
6
votes
1
answer
487
views
How are deposits of metals like tantalum located?
I am curious of how metal deposits are located in general, but to keep my question focused I wanted to just ask about tantalum for example.
Are there people who traverse their own country drilling ...
- 163
6
votes
1
answer
87
views
How do long, thin, island chains such as North Carolina's outer banks, form?
I can't think of a possible explanation, there's no volcanic activity in the area, and it gets destroyed every time a hurricane passes through. How did it get there?
6
votes
1
answer
150
views
Historically, how did the total amount of salt / NaCl on Earth develop?
After reading this question about the origin of NaCl on Earth, I'm wondering: How did the amount of NaCl develop historically? Is it a more or less linear growth until today? Was it such a linear ...
- 257
6
votes
2
answers
3k
views
Why are most minerals so rare?
There are 4,660 known minerals, so why are most of them so rare?
Is it to do with the structure of minerals?
- 111
6
votes
2
answers
942
views
Looking for a complete table of minerals for a database
I am building an open source spatial geochemical/geological observational database for mineral exploration. I need to fill the mineral lookup table.
Where can I find a complete list of all minerals ...
6
votes
1
answer
375
views
What is this geological formation in the Santa Cruz mountains that looks like a cave interior?
Stevens Canyon Road in the Santa Cruz Mountains (near Cupertino, California) passes right next to a large rock formation that, to my untrained eye, reminds me of the inside of a limestone cave. Here's ...
- 161
6
votes
1
answer
153
views
Has a scientific consensus been reached concerning the formation of the Grand Canyon?
new student of Oceanography here!
I'm studying Earth Science right now, and I found conflicting reporting re: the formation of the Grand Canyon; whether it was formed singularly by the Colorado ...
- 61
6
votes
2
answers
251
views
Actual thickness of permafrost vs theoretical maximum possibly permafrost thickness
I came across a question in my notes about why the actual thickness of permafrost is much less than the theoretical maximum possible permafrost thickness value.
The actual permafrost measure on sites ...
- 61
6
votes
1
answer
95
views
Mars maar craters explosive style formation gravitational effect
"Maars usually form when magma rises within a fissure and interacts with groundwater. If groundwater ceases to interact with magma at times during the eruption, continued magma ascent to the surface ...
- 1,952
6
votes
1
answer
91
views
How deep could an ocean trench be on Earth theoretically? [duplicate]
I was listening to a creepypasta story on YouTube about extremely deep places in the ocean deeper than the Marianas' Trench, and that makes me wonder.
On Earth specifically, how deep could an ocean ...
- 61
6
votes
1
answer
2k
views
What is the metamorphic field gradient useful for?
As I understand it, the metamorphic field gradient is the PT line traced out by the maximum temperature points of a series of PTt paths of rocks from the same metamorphic event.
What exactly is this ...
- 2,211
6
votes
2
answers
3k
views
What is the difference between nappe and thrust sheet?
The titles of many geology articles contain words like "nappes and thrust sheets". Basically these are rather similar and in certain languages can be denoted with one term. The dictionaries tend to ...
- 61
6
votes
0
answers
31
views
How to make Martian soil [duplicate]
My son wants to replicate some experiments and try to grow plants in Martian soil for his A-level science project. I know NASA have managed to produce soil that mimics Martian soil, however I also ...
6
votes
0
answers
64
views
Formation of Hematite on Mars via Perchlorates as an Oxidizer
Hematite on Mars is generally thought to have formed either in pools of water or from volcanic activity.
A comment to the answer to the question: How do hematite and magnetite form? states that ...
- 23.2k