51
votes
How did forests end up covering pyramids?
I am an archaeologist and I specialize in the ancient Maya. Here's how it happens:
1: The vast majority of ancient Maya buildings are built using a "core and veneer" technique. The bulk of the ...
- 631
42
votes
Accepted
Where on Earth is the magnetic field intensity stronger?
If we consider only the magnetic field generated by natural sources, and not the ones generated by human activities. The general trend is that higher intensities of the magnetic field happen close to ...
- 17k
16
votes
Accepted
How did forests end up covering pyramids?
The accumulation of soil in such situations takes a long time. The main way soil would have been naturally transported there would be by the wind.
The wind blown soil would get caught and accumulate. ...
- 20.2k
13
votes
Where on Earth is the magnetic field intensity stronger?
Since it is not specified in the question (and to complement the other answer), the strongest magnetic fields on Earth are not naturally generated, but artificially.
The current world record holder ...
- 331
10
votes
Accepted
For how long has the Earth been habitable for humans?
One needs breathable air, drinkable water, and food to survive. Food as we know it was nonexistent prior to the Ediacaran, which began about 635 million years ago. Life was exceedingly primitive (...
- 20k
8
votes
Accepted
At what depth does the underground begin to warm up?
Your question has an incorrect assumption built in. Near surface ground water temperatures are not generally colder, but rather reflect the average annual temperature. This will be colder than ...
6
votes
Accepted
Rate of climate change with and without humans?
The Earth should probably be cooling, at least, that's what the Milankovich cycles and historical variation and recent temperature charts all indicate.
See XKCD and related question on XKCD chart, ...
- 5,667
6
votes
Accepted
Radon is a naturally occurring radioactive gas. How does this work?
Radon (more specifically Radon-222) is produced in the decay chain of Uranium-238. Radon-223 is also produced by the decay chain of Uranium-235 and Radon-220 is produced by the decay chain of ...
- 5,667
5
votes
Radon is a naturally occurring radioactive gas. How does this work?
Radon,
occurs naturally as an intermediate step in the normal radioactive decay chains through which thorium and uranium slowly decay into lead; radon itself is a decay product of radium.
Some ...
- 20.2k
4
votes
How did forests end up covering pyramids?
Most of the Mexican pyramids are less steep than their Egyptian counterparts, and have niches and terraces which their Egyptian counterparts don't. An important difference is the climate, which is ...
- 4,453
4
votes
Accepted
Are there natural-forcings climate projections over the 21st century?
You’re right that there were no future natural forcings experiments defined in the CMIP5 protocol. The reason being simply that the modeling groups thought that other experiments were more deserving ...
- 3,133
3
votes
At what depth does the underground begin to warm up?
The temperature would stabilize to a steady temperature when you go down 15 ft or so. The point where it gets significantly warmer is probably much deeper than you want to go.
A better system ...
- 31
2
votes
How did forests end up covering pyramids?
Disclaimer: this answer is based on what I remember from school and TV.
When a volcano erupts with lava flows, the magma cools and forms an inhospitable, sterile surface. The first life to colonise ...
- 213
1
vote
How did forests end up covering pyramids?
The Accumulation of organic detritus begins when a structure is abandoned or poorly maintained. Plants that thrive without soil (epiphytes, lithophytes) are often the first generation of plants. As ...
- 736
Only top scored, non community-wiki answers of a minimum length are eligible