Reshaping the Crust

[kingwinner]

1) One type of rapid mass movements is called a "slump". I don't understand how a slump is different from a landslide...can somebody explain?

 

2) waterhed: land from which water runs off into a stream

divide: elevated region that separates two watersheds

 

These 2 definitions are from my textbook, but I am completely puzzled by them. I don't get what each of them is and I can't picture them as well...

 

3) How is a "cirque" different from a "hanging valley"? I know that a hanging valley is suspended on the mountain high above the main valley floor, but so does a cirque?! Then, how are they different?? Can someone explain briefly?

 

Thanks a lot for clarifying :)

[Turtle]

___What up Kingy! Still rockin'? Geology joke there.;) Nice to see you sticking with Geology courses so long; is it your major? I was glad to see others here help with one of your question sets last week as I would have had to hit the books myself on most of the questions.

___Todays list is more along my line & I can offer my help on the first two points.

 

2) A "watershed" is all the land that catces rain, and then by virtue of its elevation directs the fallen water downhill where it collects in a single body of water. Although the question specifies the collecting water body is a stream, lakes may have watersheds without rivers or streams per se. For example, the inner steep slopes around Crater Lake Oregon constitute that lakes "watershed". Crater Lake also illustrates a "divide", as any rain falling outside the crater collects in streams & not the lake; the crater rim divides the watersheds.

 

1) In a slump, the moving mass goes downhill more-or-less as a whole piece, with little disturbance or mixing of the interior constituent materials. In a landslide, upper layers of constituant materials fall downhill in a tumbling effect that brings lower(older) layers of the slide area to the surface.

 

:)

[Pyrotex]

1) One type of rapid mass movements is called a "slump". ...how a slump is different from a landslide... 2) watershed: land from which water runs off into a stream

divide: elevated region that separates two watersheds...

 

A landslide typically does not alter the shape of the terrain. A bunch of rocks from a mountain side break off and get loose, slide down, knock over some trees. Furthermore, what goes down the mountain is aggregate, loose rocks, soil, chunks of this and that, gravel, sand.

 

A slump is where material moves because the mountain is changing shape. The bottom or one wall spreads out. Slumps are rare as they typically require a substrate geology of soft material such as clay to lose its attachment to whatever was immediately below it (say, bedrock). Everything above the bedrock moves more or less as a unit downhill. The entire mountain side gives away all at once and slides as a unit. Sometimes, trees growing on a slump will still be upright afterwards and will continue growing.

 

Watershed: Consider a 3D model of some portion of a country. Let a drop of water fall from 10 cm above the model onto a specific Initial point on the model, coordinates Xi, Yi. Note that the drop of water slides or rolls "downhill" on the model and reaches a Final point at coordinates Xf, Yf. This final point might be a coastline, a lake, or a river.

 

Now drop a series of water droplets in a pattern of points close to Xi, Yi. As you drop more droplets, their Initial coordinates will tend to be further and further from Xi, Yi. Eventually, you will drop a droplet over every separate point of your model.

 

Many droplets will also roll to the SAME FINAL point, Xf, Yf. The set of ALL Initial points on your model, from where all droplets eventually reach Xf, Yf DEFINES "the watershed of point Xf, Yf". Since in practical application, your final point Xf, Yf is typically, say, 'A River' delta where it meets the ocean, your set of points DEFINES "the watershed of A River". It is the collection of all points where raindrops will eventually flow into A River.

 

You will also find points Xi, Yi, from which droplets may go left or go right into one of two neighboring watersheds. These points lie along the highest peaks, and on the saddle curves between neighboring peaks. This imaginary line which divides two watersheds is called a "Divide".

 

Hope that helps. :)

[kingwinner]

Can anyone explan Question 3 as well? I would appreciate~!

[kingwinner]

A landslide typically does not alter the shape of the terrain. A bunch of rocks from a mountain side break off and get loose, slide down, knock over some trees. Furthermore, what goes down the mountain is aggregate, loose rocks, soil, chunks of this and that, gravel, sand.

 

A slump is where material moves because the mountain is changing shape. The bottom or one wall spreads out. Slumps are rare as they typically require a substrate geology of soft material such as clay to lose its attachment to whatever was immediately below it (say, bedrock). Everything above the bedrock moves more or less as a unit downhill. The entire mountain side gives away all at once and slides as a unit. Sometimes, trees growing on a slump will still be upright afterwards and will continue growing.

 

Watershed: Consider a 3D model of some portion of a country. Let a drop of water fall from 10 cm above the model onto a specific Initial point on the model, coordinates Xi, Yi. Note that the drop of water slides or rolls "downhill" on the model and reaches a Final point at coordinates Xf, Yf. This final point might be a coastline, a lake, or a river.

 

Now drop a series of water droplets in a pattern of points close to Xi, Yi. As you drop more droplets, their Initial coordinates will tend to be further and further from Xi, Yi. Eventually, you will drop a droplet over every separate point of your model.

 

Many droplets will also roll to the SAME FINAL point, Xf, Yf. The set of ALL Initial points on your model, from where all droplets eventually reach Xf, Yf DEFINES "the watershed of point Xf, Yf". Since in practical application, your final point Xf, Yf is typically, say, 'A River' delta where it meets the ocean, your set of points DEFINES "the watershed of A River". It is the collection of all points where raindrops will eventually flow into A River.

 

You will also find points Xi, Yi, from which droplets may go left or go right into one of two neighboring watersheds. These points lie along the highest peaks, and on the saddle curves between neighboring peaks. This imaginary line which divides two watersheds is called a "Divide".

 

Hope that helps. :)

So basically, a watershed is an AREA with boundaries. For example, a watershed is the whole area enclosed by the red line in the following web site's animation??

http://techalive.mtu.edu/meec/module01/whatiswatershed.htm

And the "red line" represents a number of divides??

 

Your 3D model explanation is exceptionally understandable, thanks a lot!;) (I just don't think my textbook's definitions explain enough...)

[kingwinner]

___What up Kingy! Still rockin'? Geology joke there.:) Nice to see you sticking with Geology courses so long; is it your major? I was glad to see others here help with one of your question sets last week as I would have had to hit the books myself on most of the questions.

___Todays list is more along my line & I can offer my help on the first two points.

 

2) A "watershed" is all the land that catces rain, and then by virtue of its elevation directs the fallen water downhill where it collects in a single body of water. Although the question specifies the collecting water body is a stream, lakes may have watersheds without rivers or streams per se. For example, the inner steep slopes around Crater Lake Oregon constitute that lakes "watershed". Crater Lake also illustrates a "divide", as any rain falling outside the crater collects in streams & not the lake; the crater rim divides the watersheds.

 

1) In a slump, the moving mass goes downhill more-or-less as a whole piece, with little disturbance or mixing of the interior constituent materials. In a landslide, upper layers of constituant materials fall downhill in a tumbling effect that brings lower(older) layers of the slide area to the surface.

 

;)

 

I am a high school student, so nothing is my major...;)

 

1) So basically, in a slump, the falling material act as a single piece rolling down the hill without breaking and mixing??

[Eclogite]

I am a high school student, so nothing is my major...:hihi:

 

1) So basically, in a slump, the falling material act as a single piece rolling down the hill without breaking and mixing??

No. It is sliding down hill. If the components were rollingthen there would be mixing and it would not be a slump.

 

To me a cirque (or cwm, or corrie)is a small excavation in a mountain face, carved out by the source of a glacier. It is concave. A hanging valley is a u-shaped valley, carved by a glacier that was a tributary to a larger glacier whose valley it intersects.

[LOC]

I am a high school student, so nothing is my major...B)

Ahhhh.. that explains a lot. B)

 

For some reason I thought you were already studying geology in college and your posts seemed a bit like you were asking people to do your homework for you. Which, to be honest, made me feel a bit uncomfortable.

 

I did the same thing as you before getting into college. I read several books on geology to see if that's really what I wanted to study. What I would suggest you do (if you're going to continue with geology) is purchase a Glossary of Geology. A dictionary is good, too, but I find the glossary is more helpful. I bet you can find one pretty cheap one on Amazon.