Gimelist
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Why are there no volcanoes where continents collide with each other?
11 votes

Or is the continental crust too dry? Exactly this. Continental collision zones are actually full of volcanic rocks, which formed at the time before it was a continental collision zone. The Wikipedia ...

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Geodes that float in the ocean?
5 votes

Would it sink down to a certain altitude based on how hollow the geode is or would it float on top or sink to the bottom? Most geodes are made of quartz or calcite. Their densities are somewhere ...

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What is the "healthiest" rock?
2 votes

There is no good answer to this questions. All rocks contain all naturally occurring elements in the periodic table. Greater contents of an element in a rock do not necessarily translate into its ...

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Why is felsic (granitic) lava so much more viscous when flowing (or trying to) than mafic (basaltic) lava?
4 votes

Several sites said composition, not temperature, explains most of the difference... They are correct. All other factors remaining equal, felsic magmas are more viscous. This is the result of higher ...

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Did the K-T event throw dinosaurs to the moon?
4 votes

We know that there are probably terrestrial meteorites on the Moon, which got there because of impacts on Earth sending debris flying. So asking whether dinosaurs ended up on the Moon is a legitimate ...

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Why is the inner core about 85% iron and the rest (mostly) nickel, while the outer is roughly 80%/20%, if nickel is denser than iron?
2 votes

Once you're in the metallic part of the Earth, the compositions of the different constituents (solid and liquid) are not determined by density. The whole metallic part (core) is denser the the ...

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Looking for Rock/Mineral Identification Flowchart
1 votes

From my own experience of being a geologist for close to fifteen years, flow charts like that are of very limited use. The truth that you probably did not want to hear, is that it takes years of ...

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How likely are caverns inside the mantle?
Accepted answer
1 votes

It is extremely unlikely that any hollow volumes exist in the mantle. The mantle is a convecting solid which can deform over long timescales. Let's assume that such a cavern did somehow form. Whatever ...

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If people aim to reach the mantle, why don't they just use volcano craters?
Accepted answer
13 votes

why don't they just use volcano craters? Because volcano craters don't go to the mantle. Here's a sketch of how the crust, mantle, and volcanoes look like: Tan colour is crust, orange is mantle. ...

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What is the role of trace elements in magmatic crystallization?
3 votes

What is the role of trace elements in magmatic crystallization? They don't really have a role in magmatic crystallisation. Trace elements are useful because they are (sometimes) more sensitive to ...

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What gases are in the vesicles of pumice?
1 votes

Just to add to the other answers, If it's mostly water vapor in the gas, then when it cools, the pumice holes would contain liquid water, albeit small amounts compared to the size of the vesicles. ...

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How do canyons form?
1 votes

Not sure about a model you can play with, but there are some very interesting videos of models here: https://www.youtube.com/results?search_query=landscape+erosion+model

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Could one say that granites are metamorphic rocks, or not at all?
12 votes

This is the key: used to be part It is important to look at this in a historical context. Up until the 1950s and early 1960s, there was no agreement to how granites form. This became the granite ...

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Isotopic dating of metamorphic rocks
2 votes

There are two ways (at least two I will discuss here) to date a metamorphic rock. The first is using an isochron. During a heating event, isotope ratios between different minerals (most often used are ...

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Spatially-explicit global database of parent rock chemistry?
4 votes

No such thing exists. Some of the data you're looking for may be available from government geological surveys. For example, the Australian state of New South Wales provides this in their online map ...

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Why are cobalt deposits so unevenly distributed?
Accepted answer
30 votes

Part 1 The Democratic Republic of the Congo's Katanga Province contains almost 40% of the world's reserves of cobalt [1]. Why are deposits concentrated so strongly in such a small portion of the ...

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Source of heat in the center of Earth
4 votes

depths of our planet How deep? "Deep" is a relative thing. You can have 10 kilometres deep, or 5000 kilometres deep. Super high pressure at the center of it It's not the pressure per se ...

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Will Lithium batteries mean we have to exploit Co-Mn-Ni nodules from the seafloor?
1 votes

Co-Mn-Ni goes into some of the most efficient Lithium Ion battery chemistry This is correct. It is very convenient that Co-Mn-Ni is also readily available from the ocean seabed. This is less ...

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Complete missing outcrop problem
3 votes

First step - draw a strike line where line A intersects the 400 m line. Second step - you know that the sandstone layer is of equal thickness and dip, so you can draw a parallel line at the place with ...

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How did this stone become encased within different rock?
Accepted answer
5 votes

it was simply an older stone smoothed by water that had fallen into sediment. This is exactly what happened. There's a name for that: a conglomerate.

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Why should there not be water deep (e.g. below 6 kms) in the Earth's crust?
Accepted answer
3 votes

There are two reasons for this surprising finding: Compaction. Once you have high pressures at depth, the less dense material goes up. Take a bucket of water, put sand in it, and squeeze the sand ...

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Would a gold-containing meteor cause it to "rain" gold?
3 votes

Would a gold-containing meteor cause it to “rain” gold? No. First, it is a bit unclear what do you mean by "gold-containing meteor". All solar system bodies have gold, the question is how ...

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It is possible to send a probe deep within the Earth?
7 votes

First, read these three very relevant questions and answers: Why the "Mission to Earth’s core" proposal suggests using liquid iron instead of lead? Can we really travel through earth's ...

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Can there be ice in the core because of pressure?
Accepted answer
7 votes

what happens if you manage to add some water in the inner core or near it. It will probably react with the solid iron to form iron (oxy)hydride: Our observations indicate that H2O is likely ...

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Ore Deposit Identification
Accepted answer
2 votes

This is the classic description of a porphyry copper-molybdenum deposit. What happens is that there is a magmatic intrusion (the porphyry), which then solidifies. When it solidifies, it expels acidic ...

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Quartz mineral category
3 votes

quartz a silicate mineral or an oxide mineral Both. The two are not mutually exclusive. Quartz is an oxide, because it is an oxide of the element silicon. Quartz is also a silicate, because it is ...

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Feldspar content of coarse-grained igneous rocks
2 votes

Let me just add to the other answer: Plagioclase feldspar is the most common mineral in the Earth's crust. You will find it in most rocks plutonic rocks, and it is also a very common mineral in ...

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Calculating/estimating volatiles based on other representative samples
1 votes

There are several problems with what you're trying to do. First, you are looking at the H2O and CO2 contents of the rock as they are today. It is ignoring the fact that H2O and CO2 are lost during ...

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Why are there no subduction trenches on continental land?
4 votes

As mentioned in another answer: Continental crust is thick and relatively buoyant. Ocean crust is much thinner, and relatively dense. Let's look at a simulation of what might happen. Here's a figure ...

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Last ice age: did glaciers move South or move downhill?
1 votes

I think that it’s a language issue. When people talk about glaciers “moving south”, they don’t mean that any specific glacier literally moved south. They mean that the general area in which glaciers ...

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