54 votes
Accepted

Does gravity increase the closer to the core you get?

The below figure, taken from Wikipedia shows a model of the free fall acceleration, i.e., 'gravity'. The left-most point corresponds to the center of the Earth; then further right at $6.3\cdot1000$ km ...
Erik's user avatar
  • 1,999
49 votes
Accepted

Is there sand in Antarctica?

Yes. In fact, there are sand-dunes in Antarctica [1:15].
Christopher Klaus's user avatar
37 votes

What is the pressure at the center of the Earth?

It is the pressure gradient that is proportional to the local gravitational force. When that force is integrated over a distance, the pressure gradient is integrated to accumulate a total pressure. ...
Oscar Lanzi's user avatar
  • 3,831
30 votes
Accepted

Why are cobalt deposits so unevenly distributed?

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 ...
Gimelist's user avatar
  • 23.1k
27 votes
Accepted

How old is the Earth?

Yes, the age of the Earth is about 4.5 billion years (4,500 million years). Your linked articles describes well how it was formed and how we know about it. The uncertainty is less than 1% and depends ...
user2821's user avatar
  • 5,946
25 votes
Accepted

Are metals and other elements in every continent?

Metals occur on every continent . The issue is whether or not they occur in sufficiently large deposits for them to be mined economically. The difference between a mineral deposit and an ore body is ...
Fred's user avatar
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23 votes
Accepted

What do continents "lay" on?

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 ...
Antonio's user avatar
  • 947
22 votes

Why are salt domes suitable for the final disposal of nuclear waste?

Using salt domes in which to store nuclear waste has been considered in the USA and Germany. These two countries have potentially suitable salt domes. Factors in favor of salt domes are (Sect 12 of ...
Fred's user avatar
  • 24.7k
21 votes

If the Bennu asteroid were to hit within a 500 mile radius of Yellowstone National Park, will it trigger a super volcano at Yellowstone?

There is actually an hypothesis that large asteroid impacts can trigger volcanism at the antipodal point, where the seismic energy of the impact focuses. On Earth, it has been suggested that the ...
Jean-Marie Prival's user avatar
20 votes

Why is basalt denser than granite?

Magmas have a wide range of chemical (and mineralogical) compositions. Basalts come from mafic magmas (they used to be called "basic" magmas), while granites come from felsic magmas (used to ...
Jean-Marie Prival's user avatar
19 votes

If the Earth were a smooth spheroid, how deep would the ocean be?

An approximation can be obtained quite simply by dividing the volume of water in the oceans by the surface area of an ellipsoid with a smooth surface representing the idealized Earth in your question. ...
carnendil's user avatar
  • 377
19 votes
Accepted

Can ultrasounds be used to map the density of large underground regions?

Sound-like waves are routinely used to image the subsurface, but mostly well below the ultra-sound band. Several methods involve sound-like vibrations: Reflection seismic — the most important ...
Matt Hall's user avatar
  • 11k
19 votes
Accepted

What is the consensus among geologists about climate change being caused by humans?

First, a correction. Most climate scientists are climatologists rather than meteorologists. Climatology and meteorology, while related, are quite distinct sciences. Meteorologists and climatologists ...
David Hammen's user avatar
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18 votes
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What is this weird looking structure in Ethiopian desert?

Zoom in for the clues. The lines are not radiating out from the village, but from the cattle kraals. These kraals are irregular enclosures built of acacia thorn, agave and other thorny bushes. The ...
Gordon Stanger's user avatar
17 votes

How high can a mountain possibly get?

Found an article that used a simple analytical modelling to determine how high a mountain can be. Reference Based on simple physics, tallest a mountain will be on Earth is ~10 km. This is based on: ...
Earth Science Expatriate's user avatar
17 votes

Why is the temperature between the earth core and surface not distributed linearly?

The temperature does indeed increase with depth, something that is a problem in deep mines or deep drilling, but a benefit for geotermal heating. The heat originates mostly from radioactive decay, but ...
user2821's user avatar
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17 votes
Accepted

If the Bennu asteroid were to hit within a 500 mile radius of Yellowstone National Park, will it trigger a super volcano at Yellowstone?

Maybe but it will depend on the state of the magma chamber under the caldera. If the magma chamber is already under enough pressure and has a super-eruptive quantity of liquid melt in it then the ...
Ash's user avatar
  • 4,260
16 votes
Accepted

How did CO₂ originate on Earth before there was life?

The answer is Volcanos. There might be other inorganic processes capable to produce $\text{CO}_2$, but on Earth, the main inorganic source of $\text{CO}_2$ are volcanoes. In some period of Earth's ...
Camilo Rada's user avatar
  • 17.7k
16 votes

Are metals and other elements in every continent?

All stable elements (and the radioactive U and Th) exist everywhere on Earth. They're in the sand underneath your feet, they're in your bones, they're in the dust in the air, they're in the ocean. The ...
Gimelist's user avatar
  • 23.1k
15 votes
Accepted

How could this pyramidal Mountain have been formed?

Such forms tend to be created by glacial activity, which, ahem, the ice-covered continent is known for. Much discussion of this in the related question in Skeptics: Are there three pyramids in ...
jeffronicus's user avatar
  • 3,492
15 votes

What significant factors influencing geological change are still occurring?

The effects of Earth's past climate variations on the landscape, especially glaciation, cannot be underestimated. The multiple glacial advances and retreats over the last 4 million years or so have ...
Spencer's user avatar
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15 votes
Accepted

Is it safe to keep volcanic sulfur at home?

Short answer: Assuming it is sulfur (likely, but I'm not addressing other compounds in this answer) you should be fine as long as you keep it away from heat (melts at a low temperature and is somewhat ...
GrapefruitIsAwesome's user avatar
14 votes

Is there sand in Antarctica?

This LiveScience article suggests the areas aren't major: The scant areas that are free of snow and ice make up less than 0.4 percent of the continental land mass. In places there, the wind has built ...
JeopardyTempest's user avatar
14 votes

Rocks sparking under water

Is this possible? Definitely. I know you can get sparks from some rocks and minerals - but granite boulders [?] Yep. Quartz is one of those minerals that "sparks". It is piezoelectric, and ...
Gimelist's user avatar
  • 23.1k
13 votes

How long does it take for a stone to alter?

Mountains and rock do decompose or weather into sediment. A basic rock cycle overview shows the possible pathways between all three rock types (igneous, metamorphic, and sedimentary) how one type ...
Earth Science Expatriate's user avatar
13 votes

How high can a mountain possibly get?

The glacial buzzsaw hypothesis (summary; sample paper) is that mountains can't get much higher than the elevation at which glaciers form cirques. The upper walls of the cirques are steep and erode ...
cphlewis's user avatar
  • 531
13 votes

Why do some earthquakes and volcanoes occur within plates?

Crustal plates are not homogeneous, uniformly continuous rock masses with uniform stresses. They are a mixture of rock types with variable stresses and stress concentrations. They are also ...
Fred's user avatar
  • 24.7k
13 votes
Accepted

Why is Earth's density gradient a step-function, rather than smooth?

Roughly put, it's the same thing that makes a density step function when you try to combine oil and water: Source The components do not mix with or dissolve into each other, so gravity makes the ...
Oscar Lanzi's user avatar
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