Geology

[equalsmcsquared.livejournal.com]

*There are no snacks or coffee available this morning. Odd, that.*

Please don't forget to sign the roll sheet.

Today, we will begin discussing crustal deformation.

I refer you to the first figure in your handouts. The topographic map illustrated in Figure 10l-1 suggests that the Earth's surface has been deformed. This deformation is the result of forces that are strong enough to move ocean sediments to an eleveation many thousands meters above sea level. In previous lectures, we have discovered that this displacement of rock can be caused by tectonic plate movement and subduction, volcanic activity, and intrusive igneous activity.

Deformation of rock involves changes in the shape and/or volume of these substances. Changes in shape and volume occur when stress and strain causes rock to buckle and fracture or crumple into folds. A fold can be defined as a bend in rock that is the response to compressional forces. Folds are most visible in rocks that contain layering. For plastic deformation of rock to occur a number of conditions must be met, including:

*The rock material must have the ability to deform under pressure and heat.
*The higher the temperature of the rock the more plastic it becomes.
*Pressure must not exceed the internal strength of the rock. If it does, fracturing occurs.
*Deformation must be applied slowly.

Comments

[pure-blooddraco.livejournal.com]

"News spreads fast around here." he said "Hence it being best that nobody talked about it. And look at everybody, something is obviously wrong, the school isn't exactly trying to keep it hush hush."

[auroryborealis.livejournal.com]

Rory looked at him, biting her lip. "I wish they'd just make an announcement, then. Better that everyone know what really happened rather than speculate and get the rumor mill going."

[pure-blooddraco.livejournal.com]

"Exactly." says Draco. He stops himself from breathing a huge sigh of relief.

[auroryborealis.livejournal.com]

"I mean, I was there...so people keep asking me what happened," she said, staring at her hands.

[pure-blooddraco.livejournal.com]

"That's horrible. I'm sure the administration will make an announcement and everyone will stop asking. It's really not fair for them to bother you about this. It's pretty traumatizing." he said "Back home my people are at war with each other. I've never had anything like...that happen to me personally but a lot of my schoolmates have."

[12parseckessel.livejournal.com]

A small note lands on Rory's desk.

It reads:
Not too good with the words and feelings, but I can listen any time. --H.