Hot answers tagged

141 votes
Accepted

Can stone be "recycled" by melting and cooling it?

It depends on your rock. Rocks like Granite, with large crystal sizes, are the result of VERY slow cooling and crystallization. So although in theory you could remelt and recrystallize this kind of ...
user avatar
  • 6,245
110 votes

Would earthlike planets in other solar systems have well-known Earth gemstones such as rubies, emeralds and sapphires?

Crystal structure is dictated by Gibbs free energy. Once you have the right chemicals and the right conditions, nothing prevents the formation of the desired gems. The only gems you would not ...
user avatar
  • 245k
109 votes

How much damage to the US would a Yellowstone eruption cause?

EDIT: damn, this got me my first gold badge Here is a useful source, which is itself based off of this. Here is an ancillary source. WTL;DR: all the damage TL;DR: everything within 80 kilometers ...
user avatar
  • 10.2k
93 votes
Accepted

What if a portal is opened from the Mariana trench to the Sahara desert?

The climate of Earth has been roughed up quite a bit last century. But it has no idea what it's got coming with this portal of yours. Earth turns into Venus. Update: As R.M. pointed out, the amount of ...
user avatar
  • 2,593
82 votes
Accepted

Is there a scientifically valid explanation for a circle of islands?

An half submerged crater can give you a circular set of islands. You can choose among various craters: Volcanic craters, like Santorini Mountains subsided into the oceans or eroded by changing sea ...
user avatar
  • 245k
70 votes
Accepted

How could a natural road form across a sea?

Your bridge is an atoll like Kwajalein The Kwajalein Atoll is one of the largest in the world. Following the curve of the land, I estimate that the distance from the upper left to bottom right ...
user avatar
  • 84.4k
69 votes
Accepted

What size would a diamond made from a human be?

Before cremation About 18.5% of the human body is carbon by composition. One gram is five carats. The average human being worldwide masses 62 kg. Note that people may be larger in some countries,...
user avatar
  • 25k
68 votes

If the Black Sea was disconnected from the Mediterranean, how long would it take to become freshwater?

It would overflow... As of right now, the Black sea is overflowing with water, leading it to push more water out to the Mediterranean than it receives. This was not necessarily the case during the ...
user avatar
  • 84.4k
64 votes

Could we reach the earth's core using today's nuclear arsenal?

No. On this scale, the Earth is not solid and rigid. It's more like extremely hot jello, with a thin and weak crust, a layer of hot floppy jello, the "mantle", a liquid outer core (actually molten ...
user avatar
  • 19.7k
63 votes

The erosion problem on floating islands

Nothing. Eventually - over many thousands of years - a floating island will indeed be diminished until it's nothing but dust. However, individual grains of floating island don't themselves float ...
user avatar
  • 33.2k
60 votes
Accepted

A hang glider, sudden unexpected lift to 25,000 feet altitude, what could do this?

Getting caught in a thunderstorm is the most likely cause. This can happen even to experts if they are incautious enough to take risks with the weather. Here's an example with a paraglider. (I'll see ...
user avatar
55 votes
Accepted

What would it take for an island to sink and rise yearly and naturally

Give your planet two moons with different orbits, and once a year for about 30-60 days they align on the sides of the planet perpendicular to the twin islands. The tidal forces draw enough water away ...
user avatar
  • 4,262
52 votes

Physics of a metal-poor world

Could an earth-like planet form without accessible traces of iron Without iron, you'd need a completely different biochemistry, and would in practice condemn the newcomers to a slow death. Iron is ...
user avatar
  • 52.4k
51 votes

How could a natural road form across a sea?

As long as your local geography/geology permits sand deposition: a large sand bar/spit would fulfill all your requirements. Since I'm the most familiar with the geography of the Baltic, here are three ...
user avatar
  • 661
49 votes
Accepted

Gravity on a Minecraftian world?

It would be 6,378km deep. The same depth as the radius of the Earth. The math To calculate the gravity of an infinitely flat plane we simply need to integrate the force felt from concentric rings ...
user avatar
  • 48.1k
47 votes

Is there a scientifically valid explanation for a circle of islands?

For an alternative (to vulcanism) geological process, check out what was discussed in this thread at Earthscience.SE. Link to Google Map of the affected area. Basically, a very long ago tectonic ...
user avatar
  • 84.4k
45 votes
Accepted

Could terrain like this form on Earth? If so, how?

It seems likely this drawing was inspired by the real Victoria Falls, Zimbabwe and Zambia. Photographer: De Agostini Editorial/Getty Images So, yes. The Victoria Falls are a result of the Upper ...
user avatar
  • 12.8k
45 votes

How to get blue sand

You want BLUE SAND? I've got your blue sand on special today, available in the hundreds of thousands of hectares in sunny Namibia. And we are not talking those feeble green-pretending-to-be-blue sands ...
user avatar
  • 26k
44 votes

Realistic geological and chemical composition of an edible planetary surface

The big rock candy planet A planet is entirely covered in oceans. Microbial life develops on this planet. This microbial life gains energy by transforming carbon dioxide into sugar. The ocean ...
user avatar
  • 84.4k
43 votes

If Earth's Core had ALL Of the Heavy Metals

How would this difference affect Earth's overall chemistry? Not much (but see below). Here's why: Let's start with some background The core–mantle differentiation event was the melting event which ...
user avatar
  • 3,878
40 votes

How could a planet have zero surface caves?

Solid is a relative thing No caves in sand No caves in water No caves in magma No (permanent) caves in ice sheet No caves in soft soil No caves in peat bogs In short: No caves in anything ...
user avatar
  • 114k
40 votes
Accepted

How tall can a humanoid creature be without alerting the rest of the planet with earthquakes?

A real answer is a calculus problem that requires many different iffy variables that will be difficult to determine. So I am just going to ballpark it instead. In a lot of places, I have rounded or ...
user avatar
38 votes
Accepted

Creating a realistic world map - Landmass formation

While bowlturner's answer provides a list of processes to work with, I think that, since this is about worldbuilding, there should be some technique in applying all of these possibilities in a ...
user avatar
  • 5,785
37 votes

Is there something wrong with my fictional lighthouse?

Lighthouses don't necessarily mean "stay away". They can also mean "you are here". Your setup is fine if: theres lots of ship traffic within a few kilometers. or theres a hazard ...
user avatar
  • 43.5k
36 votes

Evidence of spacetime anomaly in local geology?

There is no evidence of construction in the soil surrounding the house. A Georgian mansion would have been built on site by craftsmen. They would have done much of their work on the land surrounding ...
user avatar
  • 283k
36 votes
Accepted

What conditions would make having them sunken into the ground the predominant way of building large structures?

There is no other option. The underlying rock is limestone, and it has a network of karst caves: After several attempts to build something on top of the caves, they collapsed causing damage in life ...
user avatar
  • 3,878
34 votes

Can stone be "recycled" by melting and cooling it?

An opportunity here to link up my all time favorite episode of How It's Made: Stone Wool Insulation. It is exactly melted and recycled rock, being done commercially. The idea was inspired by "Pele'...
user avatar
  • 283k
34 votes

How could a natural road form across a sea?

You could use a large mid-ocean ridge, like the Mid-Atlantic ridge, and then play around with sea levels. Mid-ocean ridges occur at (divergent) plate boundaries, and can be thousands of kilometers ...
user avatar
  • 97.7k
34 votes

Can a habitable planet have two separate crusts, both of which can sustain life?

For a given value of 'atmosphere' we already know of one such planet. Well, Moon. Europa The smallest moon of Jupiter, Europa is interesting because it is hypothesised that the surface is made ...
user avatar
  • 65.6k
34 votes
Accepted

How can I launch a projectile to hit something in orbit, using only geological structures and power sources?

It doesn't seem to be possible using "normal" geology. You'd need a supervolcano to attain the required energies, and "piloting" one with the required precision doesn't look doable. You need to score ...
user avatar
  • 52.4k

Only top scored, non community-wiki answers of a minimum length are eligible