Tour of CERI, Chapter 4 Test, and WHY Project II

 Tuesday, November 25th the 5th grade classes will walk to CERI to expand our knowledge of earthquakes.The continuing goal of CERI is to provide both scientific and non-scientific information about earthquakes and earthquake preparedness to people in the central and eastern U.S. who could someday be affected by a significant earthquake.

During the Iben Browning episode of 1990, CERI was the main regional source of earthquake information. Filling the information vacuum during the period of intense public concern had a permanent impact on public awareness and understanding of regional earthquake hazards. 

Monday, November 24th the students will be tested on Chapter 4. Please review plate tectonics, volcanoes, earthquakes, and the atmosphere.

Why Project II forms will be sent home November 20th.

Due Date: December 15, 2014

All students are in the final phase of the written component of their science research projects.  They may now choose how to share their research information. Examples are: poster, PowerPoint, Prezi, video, demonstration, diorama, model, etc.

The project due date is Monday, December 15th, 2014. I will check your progress Monday, December 8th.  I will allow three homefun free weeks to complete the presentation part of your WHYII project.

Earthquakes

Earthquakes can happen along any type of plate boundary. They also occur along faults which are large cracks in the earth’s crust. Most faults are associated with large plate boundaries where violent earthquakes usually occur. Causes of Earthquakes Earthquakes are caused when the tension is released from inside the crust. This happens because plates do not move smoothly - sometimes they get stuck. When this happens a great deal of pressure builds up. Eventually this pressure is released and an earthquake tends to occur. An earthquake starts deep below the earth’s surface at the focus.  The focus is the point inside the Earth's crust where the pressure is released. The epicentre of an earthquake is the position on the earth’s surface directly above its focus. The jerking movement caused by plates sticking then moving releases built-up pressure inside the Earth's crust, in the form of seismic waves. The waves spread out from the focus. The strongest waves are found near the centre of the earthquake. This means that the most severe damage caused by an earthquake will happen close to the epicentre. It is almost impossible to predict when they will occur. The effect of an earthquake depends on the depth of an earthquake as well as its magnitude.

Geological Features-Volcano/Earthquakes

What is a volcano?
A volcano is a mountain that opens downward to a pool of molten rock below the surface of the earth. When pressure builds up, eruptions occur. Gases and rock shoot up through the opening and spill over or fill the air with lava fragments. Eruptions can cause lateral blasts, lava flows, hot ash flows, mudslides, avalanches, falling ash and floods. Volcano eruptions have been known to knock down entire forests. An erupting volcano can trigger tsunamis, flash floods, earthquakes, mudflows and rockfalls.


Click Here to learn more about volcanoes from USGS.

How are volcanoes formed?
Volcanoes are formed when magma from within the Earth's upper mantle works its way to the surface. At the surface, it erupts to form lava flows and ash deposits. Over time as the volcano continues to erupt, it will get bigger and bigger.

What are the different stages of volcanoes?
Scientists have categorized volcanoes into three main categories: active, dormant, and extinct. An active volcano is one which has recently erupted and there is a possibility that it may erupt soon. A dormant volcano is one which has not erupted in a long time but there is a possibility it can erupt in the future. An extinct volcano is one which has erupted thousands of years ago and there’s no possibility of eruption.

Why do volcanoes erupt?
The Earth's crust is made up of huge slabs called plates, which fit together like a jigsaw puzzle. These plates sometimes move. The friction causes earthquakes and volcanic eruptions near the edges of the plates. The theory that explains this process is called plate tectonics.


What are plate tectonics?
The theory of plate tectonics is a interesting story of continents drifting from place to place breaking apart, colliding, and grinding against each other. The plate tectonic theory is supported by a wide range of evidence that considers the earth's crust and upper mantle to be composed of several large, thin, relatively rigid plates that move relative to one another. The plates are all moving in different directions and at different speeds. Sometimes the plates crash together, pull apart or sideswipe each other. When this happens, it commonly results in earthquakes.

Continental Drift: To see this animation again, just refresh this page! This animation shows you what our planet looked like millions of years ago and what it looks like now! (Graphic Credit: Geology Department at University of California, Berkeley)

Click Here to learn more about plate tectonics and the drifting of our continents.

How many volcanoes are there?
There are more than 1500 active volcanoes on the Earth. We currently know of 80 or more which are under the oceans. Active volcanoes in the U.S. are found mainly in Hawaii, Alaska, California, Oregon and Washington.


What are the different types of volcanoes?
Volcanoes are grouped into four types: cinder cones, composite volcanoes, shield volcanoes and lava volcanoes.

Cinder Cones	Cinder cones are circular or oval cones made up of small fragments of lava from a single vent that have been blown into the air, cooled and fallen around the vent.
Composite Volcanoes	Composite volcanoes are steep-sided volcanoes composed of many layers of volcanic rocks, usually made from high-viscosity lava, ash and rock debris. Mt. Rainier and Mount St. Helens are examples of this type of volcano.
Shield Volcanoes	Shield volcanoes are volcanoes shaped like a bowl or shield in the middle with long gentle slopes made by basaltic lava flows. Basalt lava flows from these volcanoes are called flood basalts. The volcanoes that formed the basalt of the Columbia Plateau were shield volcanoes.
Lava Volcanoes	Lava domes are formed when erupting lava is too thick to flow and makes a steep-sided mound as the lava piles up near the volcanic vent. The eruption of Mount St. Helens in 1980 was caused in part by a lava dome shifting to allow explosive gas and steam to escape from inside the mountain.

What is the difference between lava and magma?
Magma is liquid rock inside a volcano. Lava is liquid rock (magma) that flows out of a volcano. Fresh lava glows red hot to white hot as it flows.