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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Why is Earth's age given by dating meteorites rather than its own rocks?
Reading a course on Precambrian, I read that:
Earth Age (around 4.5 billion years) is dated thanks to the meteorites hitting Earth during its formation rather than the inner materials composing the ...
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How high can a mountain possibly get?
Mount Everest is 8,848 metres (29,028 feet) above sea level and is the result of a continental plate smashing into another continental plate. Can a tectonic process build a mountain that's even higher?...
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What do continents "lay" on?
It's a simple question.. What do continents "lay" on? Do they float on water? or are they huge bodies that "emerge" from the sea floor/bed? are they connected to the bottom of the oceans? Hope the ...
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What are the high field strength and large ion lithophile (HFS or HFSE & LIL or LILE) elements?
There are two groups of elements that are frequently mentioned when discussing incompatible trace elements. They are the high field strength elements (HFS or HFSE) and the large ion lithophile ...
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What are the causes of the supercontinent cycle?
Throughout geologic history, Earth's continents have broken apart and come together to form supercontinents multiple times, in a somewhat regular period, known as the supercontinent cycle. The length ...
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In what geological situations can I find gold?
I've heard that gold ore is often associated with quartz veins. What geological processes enable gold particles to naturally cluster together like this? What characteristics/properties should I look ...
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Why is relative sea-level falling in Hudson Bay?
Why is the sea level in Hudson Bay decreasing so much? Hudson Bay is pretty far up north, much closer to glaciers. Would it make sense for it to recede at this level with sources of fresh water ...
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Will the sea get saltier forever?
The sea wasn't always salty. It's been getting saltier over millions of years as minerals dissolve.
Is there a natural limit to this process, or the will the sea keep getting saltier forever?
Is there ...
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Are Richter-magnitude 10 earthquakes possible?
The largest earthquake since 1900 according to the United States Geological Survey (USGS) was Richter-9.5 magnitude quake in Chile in 1960. Are magnitude 10 earthquakes possible? If so, what is the ...
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Farthest point from the center of the Earth
At first glance, this seems like such a simple question of "What's the highest point on Earth". However, I also know that the Earth isn't perfectly round. So that "highest point" may be in a ...
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What caused the bend in the Emperor/Hawaii chain of islands, 45 million years ago?
What caused the bend in the Emperor/Hawaii chain of islands, 45 million years ago?
Has there been any updates to this mystery I am unaware of? Are there any new theories that could potentially ...
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What are rare earths and why do they cluster near alkaline magmatism?
'Rare earths' play a vital role in the modern economy, and they are becoming more of a point of focus in geopolitical realms. What are 'rare earths' and why do they appear to cluster in association ...
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How did Earth's plate tectonics start?
Plate tectonics is a theory which describes Earth's lithosphere as being composed of distinct plates which are able to move atop of the underlying asthenosphere. At plate boundaries, this movement ...
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How long until Earth's core solidifies?
How much longer does Earth have until the core turns solid?
Does global warming change these estimates at all?
Scottie
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What is the difference between eluvium and alluvium?
I was reading about kimberlite on Wikipedia and it mentioned eluvium. I've heard of alluvium, alluvial fans, alluvial deposits, etc. However, when I looked up eluvium, it sounded exactly like alluvium....
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Are the processes of the rock cycle currently in dynamic equilibrium?
The standard representation of the rock cycle usually looks like this:
Does each stage of the rock cycle currently balance? That is, are the various processes in dynamic equilibrium, so that the ...
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If the Earth were a smooth spheroid, how deep would the ocean be?
At the moment there are deep seas and high mountains. But imagine that the land elevation of the Earth is equal everywhere. How deep would the ocean be in that case?
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How could this pyramidal Mountain have been formed?
How could this pyramidal peak have been formed in Antarctica? Little is known about it as far as I know but what is known is that its miles away from any existing plate boundary and its shape is also ...
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In an Earth-like planet with no history of carbon-based life forms, would there be limestone?
The extent of my understanding of limestone is about what Wikipedia says at the very top of the page:
Limestone is a sedimentary rock, composed mainly of skeletal fragments of marine organisms such ...
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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 ...
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Why silicon is abundant in earth surface?
What is the reason for having silicon in so large quantity on earth surface?
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Earth's interior heat ratio between pressure and atomic decay
What is our current understanding between the ratio of Earth's interior heat between the downward pressure and atomic decay?
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How is the mass of the Earth determined?
According to textbook knowledge, the mass of the earth is about $6 × 10^{24}\,\mathrm{kg}$. How is this number determined when one cannot just weight the earth using regular scales?
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Why do crystals, like quartz and diamonds, form in different colors?
Some crystals, like quartz and diamonds, form in a variety of different colors. For example, quartz can be clear, 'foggy', pink, yellow, and even blue.
What happens during the crystal's formation to ...
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What was the first rock in the rock cycle?
I am an undergraduate student but I am a tutor at a High School, and one student asked me. Attempting to explain the rock cycle "if one rock turns into the other then which came first" my gut is ...
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What is the origin of the ocean's salt?
We know we cannot live without salt, but an investigation into the origins of ocean's salt leads one to believe that this issue is not fully resolved yet.
What geological phenomenon caused the earth ...
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Why are minerals found in "large" quantities and not scattered throughout the earth as individual atoms?
Heavier elements are created in stars. After stars die they scatter these heavier elements throughout the universe. These elements eventually gather to form planets. But why do we find "chunks" of ...
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How does one measure what causes earthquakes?
I know that they occur when energy that was previously stored is released in seismic waves. But how is the energy stored in the earth in the first place, and what can trigger the release of such ...
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How do seismologists locate the epicenter and focus of an earthquake?
I know the focus of an earthquake is where the earthquake originated from, but what I could never figure out is, how to scientists find out where exactly the focus (and epicenter) are located?
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How to make Martian soil
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 ...
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Which are the biggest methodological differences between the archaeological and geological approaches to stratigraphy?
Stratigraphy, or study of rock or soil layers (strata), was originally introduced as a branch of geology. However, it is often applied in other disciplines, especially in archaeology and paleonthology....
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How do I derive the formula for lithostatic (overburden) pressure?
The title pretty much says it. I have the formula: $P = \rho g h$ where $\rho$ is the density, $h$ is how deep the pressure is in the Earth and $g$ is the gravitational acceleration(?).
I don't get ...
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Is it ever possible for an continental plate to subduct under an oceanic plate?
It is well known that oceanic plates subduct under continental plates. This may be attributed to the plate's age and density, plus the water on top of it.
So I was wondering if it is ever possible for ...
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Why do some earthquakes and volcanoes occur within plates?
I know that volcanoes and earthquakes occur on plate margins. But, do some of them also occur within plates?
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What is the current status of geophysical global cooling theory?
Plate tectonics effectively rubbished the theory of geophysical global cooling as a means of explaining many surface features on the Earth. However, this wiki says that the same process is responsible ...
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Volcanoes in the Alps and Himalayas and the subduction of Tethys Sea
Geologist have theorized that the Tethys Sea subducted under Eurasian plates. But where are the volcanoes that would have resulted due to this? Where are the volcanoes in the Alps and the Himalayas?
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Are coral cays and coral atolls just volcanic islands?
Are coral cays and coral atolls just a different type of volcanic island? When I hear: "volcanic island" I think at places like Moorea or Hawaii, but ultimately, coral cays and coral atolls lay their ...
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If the Kola Superdeep Borehole were opened today, what would come out of it?
The BBC News article The Deepest Hole we have Ever dug says:
This is the Kola Superdeep Borehole, the deepest man made hole on Earth and deepest artificial point on Earth. The 40,230ft-deep (12.2km) ...
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Is this classification of mineral formation environments correct?
I am writing an app for students that consist in 180 sheets of the most common minerals on Earth's Crust.
One of the fields of the sheets is environment of formation.
It is important to me to ...
user12525
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How gold deposits can be formed in Himalayas?
I have heard that gold is found in the water coming out of glaciers in Skardu region of Pakistan.
Given that this area is part of Himalaya, what processes could result into ores of gold in this area?...
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Hypothetically, what would happen to the earth if a large hole was drilled through the center?
This may be a slightly unusual question. I know it wouldn't be possible, but what would the short and long term effects be, if a large (say, 1 mile diameter) round hole appeared, and went straight ...
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Oldest to Newest Bedrock in the USA "road trip"
I am supposed to design a road trip (using major highways) across North America. I have to design a route that starts with the oldest rock of Archean age and finishes with the youngest rock of ...
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Does gravity increase the closer to the core you get?
Or does the mantle and crust above you counteract the increase at one point and it actually decreases?
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How and why did the oceans form on Earth but not on other planets?
Earth is the only planet in our solar system that has copious amounts of water on it. Where did this water come from and why is there so much water on Earth compared to every other planet in the ...
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Why is Earth's inner core made of an iron-nickel alloy?
This question has puzzled me for a while. I know that earth's mantle is made of different minerals, metals and rocks etc. and that has always made complete sense to me. But why is the inner core made ...
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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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How much of a mountain is below the surface?
Is there some kind of math rule for how much does a mountain extend (depth) below the surface?
I found an article like this http://www.livescience.com/6595-depth-himalayan-mountain-roots-revealed....
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Is there a difference between rock and stone?
I couldn't find the definitions from either source:
Geology Dictionary
Glossary of Geologic Terms
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Why are oceanic plates denser than continental plates?
In the theory of tectonic plates, at a convergent boundary between a continental plate and an oceanic plate, the denser plate usually subducts underneath the less dense plate. It is well known that ...
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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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