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32

Quoting from John Russell's response to this article, "This is arrant nonsense!" Russell concludes with How did this paper get through the peer-review and editorial review processes? What technical standards were applied to determine the apparent merit of its contents so as to justify its inclusion in a reputable journal? Just because something is ...


31

Probably a bit over 4 km, in this South African mine: https://en.wikipedia.org/wiki/Mponeng_Gold_Mine But as the link mentions, the mine operators go to considerable lengths to reduce the mine temperature to endurable levels from the 66°C/151°F of the surrounding rock. Note: This answer is for the original question, where the OP asked for the deepest ...


20

Matan, the continents where we all live "float" on the Earth's mantle. The continents are made out of relatively brittle rock called the "Crust" and the mantle is made out of much more ductile material. The mantle, however, is NOT liquid. It is just much more ductile than the crust so, in geologic time, it can flow (like silly putty). Also, the mantle is ...


19

Since you termed it based on sea level, the gold mines in South Africa are not the deepest, they begin at an elevation of ~1500 m, meaning their 4 km depth is only 2.5 km below sea level. The Kidd mine in Canada is 2.9 km deep and is located at an elevation of only ~250 m above sea level making it's depth 2.65 km below sea level. https://en.wikipedia.org/...


15

What neither the authors nor the response by John Russell takes into account is that all underground oil and gas is stored inside tiny pores of rocks. An oil reservoir is not a big underground cave, it is a very fine-grained sponge made of stone filled with oil. In essentially all cases, there is more stone than oil (by volume). This means that since oil is ...


8

I'll ignore the complete impossibility of getting the world's nuclear arsenal to the center of the Earth and the impossibility of exploding them all at once. The total number of nuclear weapons, including those held in reserve and those scheduled for dismantling, is about 15000, with an average explosive power of less than half a megaton of TNT. This is ...


7

Because Al and Si were already oxidised to begin with. When the Earth formed, it had some amount of metals (Fe, Si, Mg, Al, Ca, etc) and a fixed amount of oxygen to bond with those metals. Certain metals with bond with oxygen preferentially. Mg and Ca are usually the first to take up oxygen, followed by Al, Si, and then Fe comes last (out of the short list ...


6

Thickness has nothing to do with density. The density is how much a given volume weighs. If a block of 1m × 1m × 1m weighs 60kg, and another block the same size weighs 100kg, then the second block is more dense than the other. So if the material that makes up the continental crust is less dense, then the continental crust will be less dense. This almost ...


6

Your intuition is quite correct: Other factors being equall, a dense magma will not rise through lighter rocks. The exception is if it is under pressure, in which case a fluid magma will escape through 'pressure release' pathways, either laterally or vertically (or in complex geologic structures, in a variety of irregular pathways). Magmas may begin to ...


6

(tl;dr below) First, a correction. Siderophile elements are "iron-loving" elements, those that go in the core with the Fe-Ni liquid. Uranium is lithophile, or "rock-loving". It partitions to silicate rocky material (i.e. mantle and crust) relative to the core. Secondly, But, according to this answer, the solubility of Uranium in the Earth Core is ...


6

So where did it go? Carbon was never there (or here) to begin with. You need to look at this from the opposite way. By asking "where did it go" you assuming the Earth was here first, with carbon, and then the carbon was removed somehow. But, Earth formed from a gaseous solar nebula that had all the elements. As the Earth-forming materials started ...


5

The most abundant elements are: Element Approximate % by weight Oxygen 46.6 Silicon 27.7 Aluminum 8.1 Iron 5.0 Calcium 3.6 Sodium 2.8 Potassium 2.6 Magnesium 2.1 All others 1.5 Source:http://hyperphysics.phy-astr.gsu.edu/hbase/Tables/elabund.html Based on data from a number of NASA and ESA ...


5

Divergent boundaries occur at the boundary between plates. A divergent boundary is where two tectonic plates are actively being pushed apart. Divergent boundaries create rift valleys on land and eventually ridges on ocean floors, where hotter material wells up from the mantle, cools and form new crust. For example, the East African Rift Valley (a divergent ...


5

First they do get slowly mixed at the plate boundaries but the mixing is minimal compared to the amount of crust there is. They do not mix easily since they have different densities, they tend to separate out when melted so most mixing is done in their solid states. An easy way to think of it is there is not enough continental crust to cover the entire ...


4

what is the correct term for the complete soft-layer on Earth? Sediments. Is there any term for part-of skin-of-Earth which is beneath water? Marine sediments. The soft cover is probably not being considered as Crust It is definitely part of the crust. When discussing mantle-crust issues, then crust is usually in the context of crystalline rocks, ...


4

Michael is correct. SIAL and SIMA are very vague and over-simplified summaries of the continental and oceanic crustal compositions. These terms may be OK for school introductions to geology, but you don't have to look far to find many exceptions. There are eroded and fragmented continental remnants, of nominally SIALic composition, in every ocean. Indeed, ...


4

The term "reserves" doesn't mean what most people think it does. A mineral deposit is simply a concentration of a mineral; a reserve is a deposit that is both known and economical to extract. As an example, oil shale and tar sands have both been known for decades, but only recently became oil reserves as improving technology and rising prices made it ...


4

I was about to ask a question whether this should be classified as a sinkhole or not. This is because this so-called 'sinkhole' is not entirely because of a natural process. It seems that it was the underground GPO Station (or the tunnel) of Orange Line Metro Train Station that collapsed. I can't seem to find an article that specifically mentions this. One ...


4

There is a limit to how much of a given salt can be dissolved into water, this is known as it's solubility and it's dynamic based upon how much of any particular ion is already present. Once concentrations exceed the local solubility of a given compound precipitation occurs, this can be seen in the modern Mediterranean basin with the precipitation of calcium ...


4

Step wise approach: Right now when the surface is very cold, the frost depth here (Alberta, -40 min winter temps) can reach 8 feet. Below about 30 feet seasonal temperature changes are under a degree. Around depths of 100 feet temperatures start to rise, increasing about 25C/km or 1F/70 feet. First approximation then for zero solar input (effective temp -...


4

you are missing a big factor, the plates are not moving due to the momentum of an initial impulse. They are being actively moved by the push and pull of mantle convection. Much like how icebergs are pulled along by ocean currents. the iceberg analog however breaks down because icebergs melt before they can do much complex interaction, where as continental ...


3

There is two parts to this answer, first continental crust tends to persist and oceanic tends to be recycled. This is largely due to density, continental crust is less dense and tends to "float" compared to the mantle and is very difficult to push back into the mantle for remelting. Only a tiny fraction of continental crust ever gets subducted mostly as ...


3

Isostatic means the equilibrium between the components of the crust in regards to their vertical movement owing to differences in density. Deviatoric stress is the kinda sideways stress that particles in a larger system under stress, impose on each other. It's what keeps objects from crumbling to dust when exert vertical stress on them. So, there model ...


3

There is no ocean of magma, magma only forms below when rocks have been melted due to various causes like flux melting and heat decompression, the only part of the earth that is liquid is the outer core and it is of uniform composition.


3

The SiAl-SiMa classification is very general. The continental crust is much more varied than that, but it is ok for a first approximation. The oceanic crust is dominantly mafic (aka SiMa), composed of basalt and gabbro. The continental crust is much more complex than that. The upper layer of the continental crust is felsic (aka SiAl), mostly of a granite or ...


3

Gordon's answer is correct to a first order approximation. However, the zircons that were found in Jack Hills are from the Hadean, more than 4 billion years ago. The fact that zircons that old exist is interesting - zircon is not a mineral you find in mafic rocks. Zirconium is an incompatible element in the mantle, so to get enough of it to form its own ...


3

The other answers are only partially correct. Yes the density is the key but the fundamental question is why are the continents less dense than the oceans. This is what makes the continents float higher - less dense. The reason for the density differences is due to plate tectonics. The continents are derived from two process mostly. 1) subduction zone ...


3

I honestly wish I could come up with a better answer for this question but the original article is so horrible I'm not sure where to even begin responding to it. For starters, it's published in a medical journal and if the abstract is anything to go by, the paper is constantly comparing the earth to the body. Quote: Just like the function of the thermal ...


3

Start by reading my answer on a different website: https://chemistry.stackexchange.com/a/96630/8083 This is a quick explainer on what "reserves" actually are. Lithium is mined from two main sources: a type of granitic rock called "pegmatite", and brine pools. Pegmatites are rare rocks, and lithium-rich pegmatites are even rarer and you don't find them in ...


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