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.

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15
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1answer
4k views

How much fossil fuel came from the Carboniferous?

It is said that most of the fossil fuels in existence today (coal, oil, gas) came from the Carboniferous period. A unique set of circumstances lead to the creation of fossil fuels, which depends on ...
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5answers
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Why is continental crust less dense than oceanic?

Why is it that continental crust is less dense than oceanic, where in fact continental crust is thicker than oceanic crust?
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1answer
230 views

How can scientists be confident of isotope ratios in past eras and varied locations, used for radiometric dating?

Radiometric dating relies on past isotope ratio predictions being very reliable. However, this is not necessarily so. For example, in Uranium forensics, 235U and 238U ratios are about the same for ...
11
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1answer
2k views

Determining a rock age using volcanic ash layer

I wanted to know if volcanic ash deposits found in the geologic record are most useful in correlating the age of rock layers if the volcanic ash was distributed over a large area during a short period ...
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2answers
1k views

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 ...
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1answer
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Himalayas are currently rising. What will be the highest point they can reach?

Himalayas are currently rising about 5 mm/year. What will be the highest point they can reach?
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1answer
3k views

Newton's estimate of the age of the Earth

I was reading many articles about estimates of the age of the Earth throughout the ages. I was dumbfounded when I read that Newton, arguably one of the greatest scientists ever to have ‘calculated’ ...
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2answers
150 views

Could evidence of a signal from an exocivilization be found in the geologic record?

We know that the current SETI efforts have not found evidence for the existence of intelligent exo-civilizations (XCIV). There also has not been any evidence found of ancient non-human civilizations ...
5
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2answers
679 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 ...
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2answers
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Is there sand in Antarctica?

There's a song "Blizzard's Never Seen the Desert's Sand". Given Antarctica is a desert, someone questioned the title's validity. BUT is there sand in Antarctica? I'd imagine yes as it's a pretty ...
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2answers
454 views

To what accuracy and precision do we know the volume of the Earth?

Satellites such as GOCE and GRACE measure the geoid with unprecedented accuracy. Altimeters can determine local surface elevation with millimetre-precision. This makes me wonder: to what precision ...
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Is the magma in one volcano different from the magma in every other volcano?

First off, a confession: I'm asking this question because of The Lord of the Rings. If you're not aware already, in the story, a magical ring can only be destroyed in a specific volcano. The reason ...
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Did the impact event that caused the Chicxulub-Crater definitively and single-handedly cause the Cretaceous-Paleogene extinction?

Opinions abound on the web. What is the state of the current science regarding this theory and what is the best evidence? Is the theory gaining or losing traction? If it's losing what's the best of ...
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0answers
855 views

What is the global distribution of oil filled geodes?

In a general 40 mile radius of Keokuk, Iowa many sedimentary geodes can be found. They are abundant in the Warsaw Formation with the type section at Geode Glenn in Warsaw, Illinois. In one specific ...
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1answer
272 views

Are there situations where the groundwater table doesn't follow the morphology of the surface?

In most or all geological site reports I read, the groundwater table (of the uppermost groundwater layer) always followed the morphology of the surface. Is this always the case? Are there signs for ...
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4answers
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What do the derivative or the integral of amplitude of a seismogram mean?

I'm doing a project in which I'm analyzing earthquake seismogram waves. I used a program to graph the exact amplitudes and how they changed over the course of a single earthquake. For the project I ...
12
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1answer
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Is there any correlation between La Niña/El Niño and seismic activity?

I've read in the past that extreme precipitation levels may have an effect on seismic activity, and wondered if anyone has ever analysed the La Niña / El Niño cycles to see if there are any ...
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239 views

How Can We Establish Precisely What Earth's Core is Made Of?

The consensus view is that that the Earths core is composed mainly of iron alloyed with about 10 percent nickel and traces of other heavy metals, but I have seen at least one account which says it is ...
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2answers
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Is there a "submerged object" in Australia that causes a magnetic deviation of 20 degrees?

This answer quotes this blogpost as an example of a magnetic anomaly: Basalt formation, “Mt. Jim”, in remote north-east Victoria, Australia, has a magnetic anomaly -20 degree magnetic compass ...
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2answers
358 views

What is the reasoning behind the statement "Faulting will occur along the plane where the shear stress is the highest"?

In "An Introduction to Seismology, Earthquakes and Earth Structure", authors Seth Stein and Michael Wysession made the statement: "Faulting will occur along the plane where the shear stress is the ...
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1answer
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Did an impact crater influence the formation of uranium deposits in South Australia?

As a supplementary question Did an impact crater cause the formation of the gas fields in north eastern South Australia . South Australia is a well documented uranium province. Could an impact crater, ...
7
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1answer
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How do hematite and magnetite form?

I want to understand the conditions under which hematite $\ce{Fe_2O_3}$ and magnetite $\ce{Fe_3O_4}$ form in nature. The linked Wikipedia articles explain various conditions under which they form, but ...
7
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1answer
170 views

How old are Chile's fjords?

Do we have any knowledge about the age of Chile's fjords, more specifically, those found near the Northern Patagonian Ice Field? Is it reasonable to conclude that they were formed in Quaternary given ...
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1answer
204 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?
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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 ...
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Is sterescope still used to do cartography with orthophotography?

I used this tool at my degree a couple of lusters ago to do cartography with aerial orthophotos. We used it on cartography and geomorphology subjets. Source: gumtree.com The method consists ...
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Is the Grand Canyon the "greatest" canyon in the world? [closed]

The Grand Canyon is nearly 446 km (300 miles) long, 29 km (18 miles) wide, and over 1,8 km (1 mile) deep. To the best of my knowledge, there is no other canyon of comparable size in the world. Is ...
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2answers
182 views

What would the geology and climate of a supposed landmass near the pole be like, assuming a thoroughly warmer planet? [closed]

I am designing a fantasy setting for pen-and-paper role-playing (and potential novel) purposes. I have decided that a continent be situated right on a Pole of some imaginary planet with axial tilt ...
4
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1answer
264 views

Why is Great Oxidation Event associated with Iron oxidation but not Aluminum or Silicon?

Just to build up on my previous success with oxygen origin in the atmosphere, I want to expand the question as was advised in the answers. The official heresy, despite denied in the comments and ...
4
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1answer
750 views

Are volcanoes formed from earthquakes?

I know that some earthquakes are caused by volcanoes and that some earthquakes can trigger volcanic eruptions close to where the earthquake is. But what if a great earthquake(8.0 or above) occurs and ...
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1answer
216 views

Why doesn't Earth absorb our carbon emissions?

If we look at the carbon cycle, we see that man-made carbon emission only account for a tiny fraction of all $\text{CO}_2$ emissions. However, we see a steady rise in atmospheric $\text{CO}_2$-levels....
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1answer
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Are carbonated stalactite deposits sedimentary deposits?

Acording to britanica.com: sedimentary rock, rock formed at or near Earth’s surface by the accumulation and lithification of sediment (detrital rock) or by the precipitation from solution at normal ...
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Can living where magnets are abundant provide a mini-magnetoshere?

Are there a mini-magnetosphere within the magnetosphere similar to mini-magnetosphere found on the Moon? Is there a map of these areas that would resemble the white swirls in the picture below? The ...
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1answer
787 views

Can a shock wave travel around the Earth's curvature?

Can an explosion be felt in the ground on the opposite side of the Earth like from an asteroid? Would planes in the air on that side of the Earth be able to survive? Does the shock waive follow the ...

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