10/24/14

Journey to the Center of the Earth by Jules Verne

Real-Life Rocks  What makes the sun have strong gravitational pull? The gravitational pull of an object is determined by how massive (or big) the object is and how far away fro it you are. The sun is more massive than Earth, so it has a stronger gravitational pull.

Objectives 26. Earth’s Layers (2 pages)  Differentiate among the characteristics of the earth’s three layers. (SPI ) ○ What are the three main layers of the Earth based on chemical composition? ○ What are the five main physical layers of the Earth? ○ What’s the difference between the chemical and physical layers?  Recognize that lithospheric plates on the scale of continents and oceans continually move at rates of centimeters per year. (SPI ) ○ Where are the lithospheric plates and how much do they move a year?

Question… Can anyone connect our unit on Rocks & Minerals to this new unit on Earth?

Why?  First, by studying how the Earth worked in the past, we can better understand how it is working today. This helps us understand our effects on the environment and its potential effects on us. For example, by understanding where earthquakes have occurred in the past, we have a much better idea of where they are likely to occur in the future and can be prepared for them. Second, by gaining an understanding of how Earth works, we can better predict how the Earth will react to changes. For example, if we understand how the Earth and its life responded to temperature changes in the past, we might better understand the effects of the global warming that is happening today.  So the basic point is to better understand our world. This helps us to better coexist with nature and reap the benefits that it has to offer.

1-minute Journal  Write a 1-minute journal on how a peach is like the earth’s layers.

Chemical Composition: The Four Layers The Earth is composed of four different layers. The crust is the layer that you live on, and it is the most widely studied and understood. The mantle is much hotter and has the ability to flow. The outer core and inner core are even hotter with pressures so great you would be squeezed into a ball smaller than a marble if you were able to go to the center of the Earth!

The most common rock in the crust is _________________. basalt The Earth's Crust is like the skin of a peach. It is very thin in comparison to the other three layers.

The Earth's Mantle is like the thick, fleshy inside of a peach. It is the thickest of the three layers.

The Earth's outer core is like the juice of the peach. It is so hot that the metals in the outer core are all in the liquid state. The inner core is like the pit of a peach. The insane pressures at the center cause the inner parts to stay solid.

Teach the layers of the Earth to your elbow partner. Take turns and be good listeners! Create an ACCURATE drawing the earth’s layers. You have 5 minutes!

Physical Structure: L.A.M.  The physical structure of the Earth describes how the earth moves and responds to temperatures and pressure.  The three physical structures: 1. Lithosphere 2. Asthenosphere 3. Mesosphere

Lithosphere The crust and the upper layer of the mantle together make up a zone of rigid, brittle rock called the Lithosphere.

Tectonic Plates are pieces of the lithosphere that move around on top of the asthenosphere. at centimeters per year.

Asthenosphere The Asthenosphere is the plastic or viscous layer (solid that flows) of the mantle on which pieces of the lithosphere move. This part of the mantle "flows" because of convection currents. Convection currents are caused by the very hot material at the deepest part of the mantle rising, then cooling and sinking again --repeating this cycle over and over.

Convection Currents The next time you heat anything like soup or water in a pan you can watch the convection currents move in the liquid. When the convection currents flow in the asthenosphere they also move the crust. The crust gets a free ride with these currents, like the cork in this illustration.

Mesosphere  Beneath the asthenosphere is the strong, lower part of the mantle called the mesosphere.  The mesosphere extends from the bottom of the asthenosphere to the Earth's core.  At a depth of 660 km (410 miles), pressure becomes so great in the mesosphere that the mantle can no longer flow and becomes a solid.

Reflection…