Science
Chapter 8 Introduction:
Earth's Moving Crust
Mr. Smith
https://www.youtube.com/watch?v=-D4rJCUvznA&list=PL5khOOjqgjKy_fE7zHKikBmXtvWyzYFMg&index=27
Chapter 8 Introduction:
Earth's Moving Crust
Mr. Smith
https://www.youtube.com/watch?v=-D4rJCUvznA&list=PL5khOOjqgjKy_fE7zHKikBmXtvWyzYFMg&index=27
- The tallest mountains and lowest valleys on the planet are not found on the surface of the Earth, but below the oceans' surface.
- There are rich hot-water vents on the sea floor that are full of chemicals. This is where scientists believe life on Earth began.
- Scientists are exploring several possible locations for the origin of life, including tide pools and hot springs. However, recently some scientists have narrowed in on the hypothesis that life originated near a deep sea hydrothermal vent. The chemicals found in these vents and the energy they provide could have fueled many of the chemical reactions necessary for the evolution of life. Furthermore, using the DNA sequences of modern organisms, biologists have tentatively traced the most recent common ancestor of all life to an aquatic microorganism that lived in extremely high temperatures — a likely candidate for a hydrothermal vent inhabitant! Although several lines of evidence are consistent with the hypothesis that life began near deep sea vents, it is far from certain: the investigation continues and may eventually point towards a different site for the origin of life.
Taken from: http://evolution.berkeley.edu/evolibrary/article/0_0_0/origsoflife_03
- The water vents spew chemicals and black smoke as the water is super heated by magma creeping through cracks in the ocean floor.
- The new magma cools and creates new rock on the sea floor.
- This new rock formation takes place all over the world. New land is being created as we speak.
- Rocks are being transformed (changed) constantly as the Rock Cycle changes rock from one type to another through processes we will learn about soon.
- The moving plates of the Lithosphere (that we learned about in the last chapter) create the cracks for the magma to squeeze through to create new rock.
- How rocks are changed and recycled
- How the theory of continental drift was developed
- What major feature are found on the sea floor
- What recent advances in technology have revealed about the sea floor
- How the plates of the lithosphere interact
- The movement of the Earth’s crust is responsible for the formation of many of Earth’s features. Understand the rock cycle may help contractors and builder make better choices about where and how to construct home, roads and buildings.
- Understand how and why Earth’s crust is moving may help scientists to predict earthquakes and eruptions of volcanoes more accurately.
Section 8.1 - Introduction
Weathering and the Rock Cycle – Introduction
Take a look at the picture to the left. What do you notice about the walls? See the lines? These are actually layers of sediment that have been pressed together for millennia to form rock. This rock has been worn away to reveal this path between the walls. How did that happen? How was the path created?
Weathering is the process that causes, “the breakdown of rocks into sediments.” (Science text, pg. 228) Think about licking a lolly-pop; what happens as you keep licking it? It wears away. Where did it go? Well, the sugars and coloring broke down because of the saliva on your tongue. That is what weathering does. It breaks rocks down. Sometimes the way they break down is different, and that will leave different sizes of sediment. Some sediment will get carried away by water or wind. Sometimes it will be moved around by animals, people, birds or other mechanical means. We will learn more about those processes soon.
“Over millions of years, weathering has changed Earth’s surface.” (Science text, pg. 228) In British Columbia we have the highest mountain ranges in Canada. In New Brunswick and along the east coast of the United States of America we have the oldest mountain ranges, but they are nowhere near as high as ours here in British Columbia. At 6,684 ft., “Mount Mitchell is the highest peak of the Appalachian Mountains and the highest peak in the United States east of the Mississippi River” (Wikipedia – Mount Mitchell), whereas in the west, Mount Robson is 12, 972 ft. tall. Why do you think there is such a difference? The answer is simple; millions of years of weathering. The Appalachian Mountains are millions of years older than the Coast and Rocky Mountains in the west, where wind and rain have been wearing them down. It is like the weather is licking the tops off of the mountains.
There are two types of weathering that we will learn about: Mechanical and Chemical weathering. In mechanical weathering, rocks are broken down through physical means, whereas chemical weathering wears rocks down by breaking down their chemical make-up because they dissolve the minerals in the rock, or change them into different minerals.
* _________________________________ is the breakdown of rocks into sediments
Q – What two processes cause rock to become worn down?
A - ________________________ and _____________________ weathering
Weathering and the Rock Cycle – Introduction
Take a look at the picture to the left. What do you notice about the walls? See the lines? These are actually layers of sediment that have been pressed together for millennia to form rock. This rock has been worn away to reveal this path between the walls. How did that happen? How was the path created?
Weathering is the process that causes, “the breakdown of rocks into sediments.” (Science text, pg. 228) Think about licking a lolly-pop; what happens as you keep licking it? It wears away. Where did it go? Well, the sugars and coloring broke down because of the saliva on your tongue. That is what weathering does. It breaks rocks down. Sometimes the way they break down is different, and that will leave different sizes of sediment. Some sediment will get carried away by water or wind. Sometimes it will be moved around by animals, people, birds or other mechanical means. We will learn more about those processes soon.
“Over millions of years, weathering has changed Earth’s surface.” (Science text, pg. 228) In British Columbia we have the highest mountain ranges in Canada. In New Brunswick and along the east coast of the United States of America we have the oldest mountain ranges, but they are nowhere near as high as ours here in British Columbia. At 6,684 ft., “Mount Mitchell is the highest peak of the Appalachian Mountains and the highest peak in the United States east of the Mississippi River” (Wikipedia – Mount Mitchell), whereas in the west, Mount Robson is 12, 972 ft. tall. Why do you think there is such a difference? The answer is simple; millions of years of weathering. The Appalachian Mountains are millions of years older than the Coast and Rocky Mountains in the west, where wind and rain have been wearing them down. It is like the weather is licking the tops off of the mountains.
There are two types of weathering that we will learn about: Mechanical and Chemical weathering. In mechanical weathering, rocks are broken down through physical means, whereas chemical weathering wears rocks down by breaking down their chemical make-up because they dissolve the minerals in the rock, or change them into different minerals.
* _________________________________ is the breakdown of rocks into sediments
Q – What two processes cause rock to become worn down?
A - ________________________ and _____________________ weathering
Section 8.2
Introduction
Clues in the Crust
The earth moves. Sometimes it is slow and gradual, like, “(t)he North American plate (that) is moving to the west-southwest at about 2.3 cm (1 inch) per year driven by the spreading center that created the Atlantic Ocean, the Mid Atlantic Ridge.” (Taken from, http://pnsn.org/outreach/about-earthquakes/plate-tectonics, Dec. 24, 14), or it can be fast and violent. This is how many of the mountains in the ranges on the west coast were formed. “The Rocky Mountains took shape during an intense period of plate tectonic activity that resulted in much of the rugged landscape of the western North America. The Laramide orogeny, about 80–55 million years ago, was the last of the three episodes and was responsible for raising the Rocky Mountains.” (Taken from Wikipedia, Geology of the Rocky Mountains, Dec. 24, 14)
Let’s take a look at the ocean floor in this video from The Discovery Channel. Drain the Ocean Video – Youtube https://www.youtube.com/watch?v=HVJNLSwCGHc
Now, complete the activity below by reading, Clues in the Crust on pg. 236
Matching activity - use pg. 236
Introduction
Clues in the Crust
The earth moves. Sometimes it is slow and gradual, like, “(t)he North American plate (that) is moving to the west-southwest at about 2.3 cm (1 inch) per year driven by the spreading center that created the Atlantic Ocean, the Mid Atlantic Ridge.” (Taken from, http://pnsn.org/outreach/about-earthquakes/plate-tectonics, Dec. 24, 14), or it can be fast and violent. This is how many of the mountains in the ranges on the west coast were formed. “The Rocky Mountains took shape during an intense period of plate tectonic activity that resulted in much of the rugged landscape of the western North America. The Laramide orogeny, about 80–55 million years ago, was the last of the three episodes and was responsible for raising the Rocky Mountains.” (Taken from Wikipedia, Geology of the Rocky Mountains, Dec. 24, 14)
Let’s take a look at the ocean floor in this video from The Discovery Channel. Drain the Ocean Video – Youtube https://www.youtube.com/watch?v=HVJNLSwCGHc
Now, complete the activity below by reading, Clues in the Crust on pg. 236
Matching activity - use pg. 236
1. Continental Shelf
2. Cross Section 3. Ocean Ridge 4. Abyssal Plain 5. Rift 6. Continental Slope |
A. ____ An opening in the oceanic crust, where molten materials from Earth’s mantle can escape
B. ____ A raised part of the sea floor, which can become large enough to be considered and underwater mountain range. C. ____ A drawing of what you see when you cut through an object. D. ____ A large flat area on the sea floor. They make up a large part of the sea floor. E. ____ A steep slope in the seabed between a continental shelf and the sea floor. F. ____ A shallow underwater ledge located between a continent and the deep ocean. |
Reports
Here is a video of the presentation I made to you showing examples for reports.
Use this to help you on your next report.
Here is a video of the presentation I made to you showing examples for reports.
Use this to help you on your next report.