Why so much terrain variety on Earth?

[ensonik]

Simple question: Why are large parts of the planet flat, while others are raised and mountainous? Is it related to climate and wind/rain errosion over enormous emounts of time, or was the planet just formed this way?

[haydz]

earthquakes, volcanoes, water errosion...there are many contributers!

[ensonik]

So would the Eath's terrain have been uniform around the entire sphere prior to any natural disasters?

[PiCkLed]

Weather and disasters are the main contributor to surface terrain and life that lives there.

The movement and changing of the earth side of things is

greatly to do with plate tectonics. Movement of the worlds tectonic plates away and together to push earth upwards(making most of the worlds moutain ranges which gain height everyday) or appart which allows magma to move upwards through the gap and spills out sometimes creating islands in the ocean ect. The Pacific ring of fire is an example of this.

The original state of the earth isnt totally known. When the planet was forming the greatest amount of change was meant to have happened due to the surface being very active. What we see now is nothing compared to what it was originally and is very tiny these days cept for the odd explosion of volcanoes.

[Newtonian]

So would the Eath's terrain have been uniform around the entire sphere prior to any natural disasters?

It wasnt,there are less earthquakes,and volcanic activity now. Than was taking place earlier in the history of our planet.

[coquina]

The USGS website "This Dynamic Earth" is the best place I know to learn about why the earth isn't flat as a pancake:

 

http://pubs.usgs.gov/publications/text/dynamic.html

 

This page on the "Wilson Cycle" is good too:

http://csmres.jmu.edu/geollab/Fichter/Wilson/Wilson.html

[ensonik]

The USGS link is very informative, thanks.

[syntax252]

The USGS website "This Dynamic Earth" is the best place I know to learn about why the earth isn't flat as a pancake:

 

http://pubs.usgs.gov/publications/text/dynamic.html

 

This page on the "Wilson Cycle" is good too:

http://csmres.jmu.edu/geollab/Fichter/Wilson/Wilson.html

 

Actualy, it probably is as flat as a pancake--relatively speaking that is.

[Tetrahedrite]

Actualy, it probably is as flat as a pancake--relatively speaking that is.

Huh????

[coquina]

Huh????

 

I think what Syntax meant was that when you look at a cross section of the earth, the heights of the mountains and depths of the ocean are small compared to the whole thing.... as is illustrated by this photograph:

 

http://images.google.com/imgres?imgurl=http://www.electrickiva.com/chs_spring_2004/Unit_EarthScience/03/earth_cross-section_lg.jpg&imgrefurl=http://www.electrickiva.com/chs_spring_2004/Unit_EarthScience/03/earth_cross_section.htm&h=634&w=654&sz=94&tbnid=uHvRQwM9nF0J:&tbnh=131&tbnw=135&start=3&prev=/images%3Fq%3Dearth%2Bcross%2Bsection%26hl%3Den%26lr%3D

 

He and I are both machinists, and are used to dealing with scale models.

[ensonik]

Thinking about this some more, and I can't help but imagine that particles attracted together by gravity within a nebula would form a uniform spherical surface. So is it off base to assume that prior to disruptions caused by plate techtonics and so forth, the earth was uniform?

 

And speaking of the creation of planets, what is the current explanation for why random particles within a nebula would in fact be drawn together towards an empty spot in space to eventually form a planet? What is the "motivation" so to speak for random particles to form together at some arbitrary point?

[syntax252]

I think what Syntax meant was that when you look at a cross section of the earth' date=' the heights of the mountains and depths of the ocean are small compared to the whole thing.... as is illustrated by this photograph:

 

He and I are both machinists, and are used to dealing with scale models.[/quote']

 

Bingo!

[coquina]

Thinking about this some more' date=' and I can't help but imagine that particles attracted together by gravity within a nebula would form a uniform spherical surface. So is it off base to assume that prior to disruptions caused by plate techtonics and so forth, the earth was uniform?

 

And speaking of the creation of planets, what is the current explanation for why random particles within a nebula would in fact be drawn together towards an empty spot in space to eventually form a planet? What is the "motivation" so to speak for random particles to form together at some arbitrary point?[/quote']

 

In your first paragraph, what you're not taking into consideration is that Earth has a molten interior. Convection currents form in the interior - that is what drives the movement of the plates.

 

As to the accretion of the planets - the sun's gravity pulls in the more dense materials close to it - that is why the inner planets are rocky and the outer ones are gaseous.

 

The particles bump together and gradually adhere. At some point one of the chunks gets large enough to attract more particles by its gravitational force.

 

That is a very loose explanation about what I read some time ago. I think there are various theories as to the details.

[Mokele]

The Annals of Improbable Research, proving that there's *nothing* people won't write a paper on:

 

Kansas is flatter than a pancake

 

Mokele

[Guest swim chick]

Simple question: Why are large parts of the planet flat, while others are raised and mountainous? Is it related to climate and wind/rain errosion over enormous emounts of time, or was the planet just formed this way?

IT'S COMPLETLY TO DO WITH THE MOVEMENTS OF THE TECTONIC PLATES

[AzurePhoenix]

If by completely you mean "partly but not entirely", then yes.

[Oceansman]

So here related to the plate techtonics theory - this last fall my Physics 2 professor on one of his frequent scientific asides mentioned that there is another theory that has caught on recently (a new theory I am almost certain) that comes at the motion of plates from anoither angle, does anyone know anything more about this?