Question about earth.?

Question

According to the Time scale some early creatures about billion and billions of years ago dominated the Earth.

If it happened so a long, long time ago.
Then why is it that the mountains today are still standing? (Considering factors such as erosion and the like.)

Answer 1

The mountains you see today are not necessarily the same as they were millions of years ago, Remember, animals have only walked on land for the past 250 million years, not billions of years. That said, erosion takes eons to wear away a solid piece of granite ( like the Rocky Mountains),
earthquakes can do more damage quicker. Go to a beach and look at the different stages of eroded rocks, stones, pebbles and sand. Some were once, mountains and others were purely sediment.

Answer 2

As simply put as it can be, most mountains you see today were once a lot higher but erosion and time have worn them away. If you look at the difference between the the mountains of the Eastern US and Western US, you'll notice that the Eastern mountains are lower and more rounded. It's because these are older mountain systems. Some mountains, however get taller. In fact, there was a debate a while back whether Mt Everest was still the tallest mountain in the world. Mountains get tall by subduction and lifting. Take both hands and lay them flat on a table with your finger tips pointing toward each other. Now move your hands together. You'll see that the fingers of one hand have to go either under or over the fingers of the other hand. Mountains do this. Going over is lifting and going under is subduction. The space between your hands is a fault. So some mountains get pushed up at the same time they're being worn away by erosion. The fastest occurrence wins.! :-)

Answer 3

they are not. not a single mountain today has been around 2 billion years ago. not as mountain anyway. corrosion and the earth mantle's movement have levelled everything that was outside the horizontal alignment in those days. but mountains are build all the time, some, like the himalayas which are still being pushed upwards by india crashing into asia, actually grow as we speak. (or as i write this, rather :)).

so the mountains you see today are much younger, like only a few dozen million years...

( in case you are calculating now... yes, todays mountains didnt even see the dinosaurs, let alone their earliest ancestors.)

the earth is a pretty turbulent place in geological time frames. you better get a hold of something ;)

Answer 4

First of all, the mountain ranges all around the earth's surface are a result of both earthquake & volcanic activity. Earthquakes occur when there is a sudden slip on a fault. This results in the shaking of the ground at the earths surface caused by the slip or by underground volcanic activity. A fault is a fracture along which the sections of crust on either side move relative to each other & parallel to a fracture. They can be both vertical (up to down) or horizontal (side to side). Below the earth's surface are layers that consist of:

1. The solid core at the center, surrounded by,
2. Hot molten lava, which is surrounded by,
3. The mantle, which is surrounded by,
4. The outer crust or surface of the earth.

Imagine a bowl of jello with a marble in the center acting as the earths core. The jello can be compared with the metallic or molten lava surrounding the earth's core. As the jello moves around the core (or marble), a shifting action occurs. This causes the layer on top of the molten lava called the mantle to move in a variety of directions. When this mantle is moving, the earths crust, or the part we walk on, moves in all kinds of directions. This is what we call an earthquake.

Billions of years ago as the earth was born, the mantle moved into sections of mantle-like plates, scientests have called Tectonic Plates. These plates consist of an outer layer of the earth called the crust or lithosphere which is cool enough to behave as a hard shell made of dirt and rock. Sometimes when the molten lava, or mantle-like plates (Tectonic Plates) found a weak spot in the crust, it began to move upwards like a bottle full of coke that you shake up then pull the top of off. All that coke fizz can be compared to the lava rising up through vents, or holes in the earth, we call today, volcanoes.

Since the crust is so brittle, it breaks or fractures easily, like a saltine cracker; And the cracker we stand on is the crust which shakes called earthquakes.

Now, how does all this sum up to become today's explanation of how mountain ranges came to be what they are? And why did all this occur at a time when the dinosaurs ruled the earth?

Well, the earth's mantle releases internal heat by convection, like a pot of pudding on the stove. This pudding or lava, coming out of volcanoes creates new land on the earth's surfae, or makes the crust more thicker. The process of making new land and mountains is equal to the speed of a really slow snail! It is about the speed of a few centimeters a year. So as you can see, if it took only a few centimeters a year to create all the land crust or surface that we walk over today; just think how long it must have taken for all of the mountain ranges to become the shape of such high snow-bound peaks! After a few million years, the mantle heats up all over again, and is recycled back to the center area in the volcano from where it came from when it started.

Now that we know land features are created only over millions and billions of years; that makes more sense as to why dinosaurs walked the earth when the volcanoes, and mountains were being formed.

About the mountain ranges. The tectonic plates that move actually formed the continents we have today. Most of the mountain ranges you see on a map or a globe, have occurred where the plates once pressed up against each other. And when they pressed against other, it was like all that dirt and rock, had no place to go but up!! And so, there you have the Rockie Mountains of N. America; The Andes of S. America; The Himalayas of Asia; The Caucasus Mtns. of Europe; and Mt. Kilimanjaro of Eastern Africa. The same thing happened on the ocean floor, & caused what scientests today term Oceanic Rifts or ridges trenches or deep canyons.

There are 3 main tectonic plate types: extensional, transform, and compressional. Each cause a different result on the earths surface because each is simply a movement in a different direction of the plates under the earth's surface.

Earthquakes that cause extensional features on the surface of the earth, occur when two plates have moved away from each other, and as one plate moves down at an angle from the other. This will make the crust move away in opposite directions, like two boys playing tug of war with a rope. The plates move away from where the earthquake started called the ridge. As the ridge cools, it then sinks. And a good example of extensional ridge type of earthquake can be found in the Sinai Peninsula area of the Middle East. Just look at a globe, find the continent of Africa, and start moving your finger from the top and left hand corner of Africa along the coast towards the right until you reach the end of Africa. The country you should end up with your finger on is Egypt. And the country you should start with, would be correct if your finger was found on a country named Morroco.

Transforms, are caused by earthquakes that are shallow, and cause two plates to separate in a kind of North to South movement. And a real good example is the San Andreas Fault in California. These can actually separate in any direction though.
Like East to West, and even diagonally.

Compressionals are caused by earthquakes that happen when two plates move against each other which is what causes mountains to rise up from beneath the earth's surface. And any mountain range you find, look at, or snow ski down its slope, is a good example of this kind of earthquake.

For a little trivia, ask this question in your next science or geography class then answer it! Which state in the U.S. has an example of all 3 types of earthquakes:

extensional, compressional, and transforming?

The answer is Nevada.

Answer 5

Mountains still stand today due to many factors. Take the Himalayas, the Indian-Australian and Eurasian plates are still colliding very slowly. This collision is ever so slightly increasing the mountains' height.

Answer 6

Mountains are eroding however the world is in a constant flux. There are mountains being made (volcanos) and canyons being carved by rivers. Glacers have changed our landscape during the ice age. Wind, rain, earthquakes change the earths surfaces and land masses have broke apart and moved or shifted the landscape.

Answer 7

The mountains standing today weren't doing so many millions of years ago.

The surface of the earth are giant plates, moving around, bumping into one another, sliding on top of one another. When they do this, some bits of the plate edges get shoved underneath on another: some go underground, some get shoved higher up in the air. Voila, mountains!

Answer 8

Earthquakes move the ground making new mountains and the valeys can erode too