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Both of these mountain ranges were created (and are still growing) because of tectonic plates colliding. There is one significant difference between them though, as we shall see below.


One of the ways in which mountain ranges can be built is when tectonic plates collide.

The continent of India was on its own plate, and was joined to the supercontinent called Gondwana. When Gondwana broke up, India was carried northward by tectonic forces, and eventually 'crashed' into Asia. It is still moving north at the rate of about 5 cm per year. This has resulted in a (still growing) mountain range which is made of continental crust rising at the junction between these two plates.

Because it is made up of continental crust on both sides (Indian & Asian), it's lighter than oceanic crust. So, there is almost no subduction, and hence no volcanic activity in the zone (although there are earthquakes). These mountains are being 'bulldozed' up. In some places, the crust may be as thick as 70 odd km.

The Rocky Mountains (like the Andes), are the result of another type of plate collision. In this case, a continental plate meeting an oceanic one. In the case of the Rockies, this is because the N American plate is moving roughly west-southwest at about 2.3 cm per year.

This causes subduction because continental crust is lighter, and rides over oceanic crust, thus pushing the oceanic crust down into the mantle, where it melts, and eventually forces its way back up to the surface as lava.

If you're not sure what subduction is, this slide explains it:

It is from image.slidesharecdn.com.


Several things can happen


Part of it will evaporate, part will soak into the soil, and part will flow off to lower regions, where it may gather into rivers and finally into the sea. Part of the soaked up water will also eventually follow one of the other routes.
All of these possibilities, and the ratio between them, are subject to the local conditions, such as temperature, type of soil, height gradient, and more.


It depends on the medium that they're travelling through.


P-waves (also called pressure waves and/or primary waves) are the first waves to be seen on a seismograph, which makes them the fastest travelling waves. The waves' speed depends on the medium they're moving through, such as liquid (water, oil), solid (rock), or a gas, in addition to the inclusion of fractures or vesicles in solids. Density also plays a very significant role.

The generic answer is 5 to 8 km/s, but they can travel much faster or slower depending, of course, on the matter they're moving through. The fastest speed, as shown below in the image, is the propagation through the earth's core, near 14 km/s (though it's generally referenced as approximately 13 km/s).

The speed of p-waves is relatively slow through some looser solids, like scree (smaller rocks) and substances that are mostly solid, like soil. These can be as low as 300 m/s, which is slower than the generally referenced speed of sound (about 340 m/s at sea level).

It is much faster through the more dense rock, like basalt or its intrusive cousin, granite (upwards to approximately 6 km/s each). Below is a good reference table.

Also note that I use the word "speed" while most people use "velocity" to describe the rate of propagation of the waves. Technically speaking, speed is the more correct terminology since there isn't a direction referenced for it to qualify to be labeled as a vector quantity (unless, of course, you choose to reference one, but that's not really how waves work).


Stanford Rock Physics Laboratory


Earth's four spheres are: the lithosphere , the atmosphere , the hydrosphere , and the biosphere .


Every thing on Earth can be placed in one of the four major subsystems or spheres.

The Lithosphere refers to the land mass which includes all forms of terrestrial structures and zones.

The Atmosphere refers to the blanket of air that covers the air which is itself divided into subspheres: the troposphere, the stratosphere, the mesosphere, and the thermosphere which contains the ionosphere and the exosphere.

The Hydrosphere refers to all water bodies, liquid and frozen (sometimes called the cryosphere), salt and fresh, surface or underground.

The Biosphere refers to all living creatures that exist.



Two reasons.


The first reason is it is if you know the wind speed and direction you will know what direction the weather is coming from and how fast it is moving. For example, if it is raining at a town 80 nautical miles (wind is measured in knots official) to the west of a second town, and the radar returns show that the precipitation is moving to the east at a speed of 20 kts, a relatively accurate prediction for the second town is that in 4 hours time it will be raining.

More importantly, wind direction and speed helps to plot the atmospheric pressure. The Buy Ballot law states that in the Northern Hemisphere, if the wind is at your back the area of low pressure is to your left. When you plot many wind points you get a pattern that illustrates the pressure pattern and when you look at speed you get an idea how far away the location is from the center of the pressure center.

enter image source here


This map shows how plotting the wind can show you the location of the pressure center. The thing to remember is that sometimes measuring stations are more than 100 miles apart, so plotting the wind like this can really help.


Primarily it's the chemistry of the minerals. Following this is the crystal structure of the minerals.


Minerals are primarily grouped by their chemical composition, in one of the following categories:

Natives - these are single element minerals, like gold and silver.

Some minerals share the shame chemical composition (polymorphs), so the chemical composition alone is enough to uniquely group them. This is an example of when crystal structure is necessary to group some minerals (examples are the aluminosilicates kyanite, andalusite, and sillimanite).

The properties of minerals are not enough to uniquely separate them into groups, since so many minerals share the same properties. Organization would be very difficult, and it would lead to too many groups. In addition, many minerals have variations in their physical properties, making it even more difficult to accurately group them into a set group. Going further, optical mineralogy opens up a new bucket full of different diagnostic features, further complicating this matter.

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