L5+Fecteau+Cameron

**COLLEGE OF EDUCATION, HEALTH AND REHABILITATION **  **LESSON PLAN FORMAT **       Maine Learning Results: Science and Technology - D. The Physical Setting D2. Earth Grade 6-8 Geology Students describe the various cycles, physical and biological forces and processes, position in space, energy transformations, and human actions that affect the short-term and long-term changes to the Earth. f. Give examples of abrupt changes and slow changes in Earth Systems.      Students will have a discussion with their peers pertaining to the question that they just were confronted with. Students will also complete a blog entry throughout the lesson to see that understanding is being practiced. The graphic organizer will also be collected and looked at to observe the students' understanding. The students will collect their ideas into a rough draft of the script that will be included in the final product. Class discussions will also help determine whether or not students have a good grip on the material. At the end of the class I will have the students bow their heads and close their eyes. They will then give me a thumbs up, a thumbs down, or anywhere in between suggesting their understanding. A confidential photograph will be taken for a visual artifact to see my students' progress. I will also check for students' understanding by looking over their script rough drafts. <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">An IMovie newscast- students will be able to imagine what the Earth would be like without the four boundary zones in a newscast and incorporate it onto IMovie. <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> As the teacher, I will not be using technology in the hook. Also, I will be logging onto the students' blogs to see how the progress of understanding is going and be able to comment on them. In their blogs, I will also be checking their rough and final drafts of their IMovie scripts. The students will be using three types of technology in this lesson. They will work with the blogging for their rough and final drafts, checking their peers’ scripts, and for their learning reflections. The second technology that the students will be using is the IMovie software. Lastly, if the students choose to do the extension with Comic Life, rather than the blog, then they will grasp that technology as well.
 * <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">UNIVERSITY OF MAINE AT FARMINGTON **
 * __<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Teacher’s Name __****<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">: **<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Mr. Fecteau** __Date of Lesson__:** 5
 * __<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Grade Level __****<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">: **<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">6 - 8** __Topic__:** Imagine; Geology/Earth
 * __<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Objectives __**<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">
 * <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Student will understand that **<span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> the four boundary zones cause immediate changes upon the Earth's surface.
 * <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Student will know **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">the mechanical features of the boundary zone so that when they experience such things like volcanic eruptions and earthquakes, they know what is physically happening to the Earth. <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">
 * <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Student will be able to **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">imagine what the Earth would be like without the four boundary zones in a newscast and incorporate it onto IMovie. Product: An IMovie newscast. <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">
 * __<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Maine Learning Results Alignment __**
 * <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Rationale: **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">This lesson will be completed by the students through Think-Pair-Share in the cooperative learning and will be self-assessed by using a given checklist before handing into me. <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">
 * __<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Assessment __**
 * <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Formative (Assessment for Learning) **
 * <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Summative (Assessment of Learning) **
 * __<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Integration __**<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">
 * Technology: **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">

Art: Before the students start thinking about their final product, they are going to sketch what the Earth might be like if there were no boundary zones. <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Think-Pair-Share: As students enter the classroom they will draw plastic army men from a bag. Students will pair up during the cooperative learning by the army men that have the same position and weapon. Students will be confronted with a question written on the board and individually think of answers. Next, students are paired up and compare answers and complete graphic organizer together. As a class, they share their graphic organizers and students are able to make changes throughout the class discussion. <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> //** I will review student’s IEP, 504 or ELLIDEP and make appropriate modifications and accommodations. **//**<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">
 * Subject:**
 * __<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Groupings __**<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">
 * __<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Differentiated Instruction __**
 * <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Strategies **
 * Verbal: **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> Discussions in pairs, then sharing their ideas with the class, and introductory discussion.
 * Logical:** The graphic organizer: Four-Column Chart and rough draft of script.
 * Visual:** The IMovie product, graphic organizer, opening sketches, and the script.
 * Bodily-Kinesthetic**: Students will be acting in their IMovies.
 * Musical**: Music should be incorporated into their IMovies.
 * Interpersonal**: The students are confront with a question, which they will be given time to individually think.
 * Intrapersonal**: Students go into pairs after individual thinking and share with the class.
 * Naturalist**: Students can use Google Earth to see arial photos of volcanoes. <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">
 * <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Modifications/Accommodations **

<span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Students will be asked to do some background research on specific boundary zone changes in the present day world. I will ask them to find the most recent volcanic eruption and the most recent earthquake. Students will have the option of either incorporating it into a blog entry or a Comic Life version. Each change should be a page on Comic Life. <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Sketch paper Laptops Blog account Graphic organizer Pencil/pen Army men Checklist Bag IMovie software Video camera Google Earth software <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> [] In depth text of boundaries. [] All three seen here. [] Plate boundaries that can be found throughout the world. [] Video clips of boundary actions. [] Side links on plate tectonics. [] Definitions and an in depth look of boundaries. [] Diagrams and specific definitions and explanations. [] Real life pictures/models.
 * Absent Students:** **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> If a student misses a class, then they are expected to get the class notes from his or hers peers. If a particular assignment was due the day of their returning, then they are also expected to have it completed the following day for me. If a student is incapable of doing the assigned work, then a note from a doctor or parent will be taken into consideration for an extended due date. If no note is given, then the student will receive a zero for the assignment. If the student also fails to turn in the homework assignment even with the extended due date, then the consequences are the same as the regular. <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">
 * <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Extensions **
 * __<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Materials, Resources and Technology __**
 * __<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Source for Lesson Plan and Research __**
 * Boundary Zones **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">

[] Many resources here. [] Easy resource to use. [] Animations. [] What, Why, News, History, How, & Future.
 * Volcanoes**

[] History of earthquakes. [] Maps and lists. [|http://earthquake.usgs.gov/learning/kids//] Fun activities. [] Quiz and background info. <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">As students are undergoing the lesson, particular students that need the set procedures and the structural setup will find lesson five comforting. At first we will ease into the criteria and then slowly descend as time goes on. The instructions will be viewable on the board for everyone to see what we are doing. As for students that want to understand exactly why the Earth acts the way it is, this lesson was designed exactly that. The mechanics of boundary zones and the specific formations are looked at, which better defines what the Earth is undergoing and the changes that may occur. The cooperative learning was meant for those who best build off of their peers and look for other's guidance. Students will not only learn from each other, but also compare each other's knowledge. Lastly, for those students that need the spark of excitement to learn, then they will find the hook and army men entertaining. If students want to go more in depth with the product, then the option of finding present day changes can be completed. <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">The facet that this lesson is using is Self-Knowledge. Students will be able to imagine what the Earth would be like without the four boundary zones in a newscast and incorporate it onto IMovie. The final product will be an IMovie newscast. This lesson will be completed by the students through Think-Pair-Share in the cooperative learning and will be self-assessed by using a given checklist before handing into me. For contents notes, please see below Teaching and Learning Sequence section. <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">
 * Earthquakes**
 * __<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Maine Standards for Initial Teacher Certification and Rationale __**
 * //<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Standard 3 - Demonstrates a knowledge of the diverse ways in which students learn and develop by providing learning opportunities that support their intellectual, physical, emotional, social, and cultural development. //**
 * <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Rationale **<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">:
 * //<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">• Standard 4 - Plans instruction based upon knowledge of subject matter, students, curriculum goals, and learning and development theory. //**
 * <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Rationale **<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">:
 * //<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">• Standard 5 - Understands and uses a variety of instructional strategies and appropriate technology to meet students’ needs. //**
 * <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Rationale **<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">:
 * Verbal: **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> Discussions in pairs, then sharing their ideas with the class, and introductory discussion.
 * Logical:** The graphic organizer: Four-Column Chart and rough draft of script.
 * Visual:** The IMovie product, graphic organizer, opening sketches, and the script.
 * Bodily-Kinesthetic**: Students will be acting in their IMovies.
 * Musical**: Music should be incorporated into their IMovies.
 * Interpersonal**: The students are confront with a question, which they will be given time to individually think.
 * Intrapersonal**: Students go into pairs after individual thinking and share with the class.
 * Naturalist**: Students can use Google Earth to see arial photos of volcanoes.

Type II technology will be used by students through blogging after every class for reflection. In addition, students are also blogging about any other addition questions if asked. A second technology used by the students for their final product is their IMovie newscasts. <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">After finishing the IMovie newscast the students assess themselves with the checklist before handing the final into the teacher. Students will also complete a blog entry when the pairs meet to see that understanding is being practiced. The IMovie newscast will be the students' final product. Students are using their graphic organizers, script rough drafts, peer and teacher feedback, and then creating a IMovie newscast which will be accompanied by a final script. <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> Students enter class they will draw plastic army men from a bag. Raise hand for silence. Hook; Personal sketches and discussion about situation brought forward. Time: 5 minutes Go over instructions on the whiteboard. Time: 5 minutes Students are given time to individually brainstorm. Time: 5 minutes Students get into pairs and discuss concepts. Time: 15 minutes Pairs share ideas with class. Time: 10 minutes Class discussion. Time: 25 minutes Feedback on graphic organizers. Time: 10 minutes Research and work on rough draft of script. Time: 30 minutes Photograph for understanding. Time: 5 minutes Blogging: Time: 10 minutes
 * //<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">• Standard 8 - Understands and uses a variety of formal and informal assessment strategies to evaluate and support the development of the learner. //**
 * <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Rationale **<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">:
 * __<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Teaching and Learning Sequence __****<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">: **<span style="font-size: 12pt; font-family: 'Times New Roman','serif';">
 * Day 1 **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">

HW: finish rough draft of scripts.

Raise hand for silence. Get into army men pairs. Peer edit rough drafts. Time: 30 minutes Revise into final draft. Time: 25 minutes Start brainstorming/filming for IMovie. Time: 50 minutes Photograph for understanding. Time: 5 minutes Blogging: Time: 10 minutes
 * Day 2**

HW: finish the IMovie or at least a decent chunk of it.

For the fifth lesson students' working surfaces will be arranged in a two's formation. This arrangement will be handy for when the cooperative learning process for when go from individually working to working in pairs. As students enter the classroom they will draw plastic army men from a bag. Students will pair up during the cooperative learning by the army men that have the same position and weapon. When the students are seated and somewhat prepared for class, I will raise my hand before them and wait for them to quiet down. This method relies on other students to quiet down their peers. When they see my hand raised, they are to raise their hand as well and remain quiet. When their peers see each other doing this, they will shortly follow. At this time I would then introduce the students to the hook, which is simply the students being confronted with a question and making a sketch. The question I will ask will pertain to what the students already know about plate boundaries. I will ask them what the Earth might be like if there were no boundary zones. Afterwards, students will be handed a graphic organizer and we will go over the instructions on the board. They will then go into the cooperative learning of Think-Pair-Share. Students will use their sketches as a starting point to individually fill out their organizers. As they go into their final products, they will be able to use these personal resources, as well as outside resources. Students will understand that the four boundary zones cause immediate changes upon the Earth's surface. Students will need to know the mechanical features of the boundary zone so that when they experience such things like volcanic eruptions and earthquakes, they know what is physically happening to the Earth. Students describe the various cycles, physical and biological forces and processes, position in space, energy transformations, and human actions that affect the short-term and long-term changes to the Earth//.//
 * What, Where, Why, Hook, Tailor: Visual, Verbal, Bodily-Kinesthetic, Intrapersonal, Interpersonal, Logical, Naturalist**

Students will need to know the Convergent, Transformation, Divergent, and Subduction zones and how they create instant changes on the surface of the Earth. I am going to deliver the instructions by writing them on the board clearly. After the hook, I will verbally outline the instructions so that the students understand their mission. Once I have finished going over the instructions, I will ask if anyone has any questions on what is expected of them. Throughout the class I will be falling in and out of the pairs and answering any raised hands. I am continuously monitoring my students. The students' understanding will be checked by the class discussion and by me collecting their graphic organizers and giving positive feedback. The rough drafts of their script will also be checked for understanding. At the end of the class I will have the students bow their heads and close their eyes. They will then give me a thumbs up, a thumbs down, or anywhere in between suggesting their understanding. A confidential photograph will be taken for a visual artifact to see my students' progress. For contents notes, please see below Teaching and Learning Sequence section.
 * Equip, Tailor: Logical, Visual, Bodily-Kinesthetic, Verbal, Intrapersonal, Interpersonal, Naturalist**

For this lesson students will be handed a graphic organizer titled Four-Column chart. Think-Pair-Share: As students enter the classroom they will draw plastic army men from a bag. Students will pair up during the cooperative learning by the army men that have the same position and weapon. For example if a student was to select a army man that was laying down with an M-16, then they would try to find a peer that has the same action figure. Students will be confronted with a question written on the board and individually think of answers. Next, students are paired up and compare answers and complete graphic organizer together. As a class, they share their graphic organizers and students are able to make changes throughout the class discussion. Students are able to make changes to their graphic organizers during the class discussion. Students will develop a rough draft script of their news broadcast and peer edit each others. Students will apply their IMovie production to a given checklist to see if all requirements are met. Students will be able to imagine what the Earth would be like without the four boundary zones in a newscast and incorporate it onto IMovie. The final product will be an IMovie newscast. I will facilitate the learning process by starting with the teaching session and going well into the graphic organizer or Four-Column chart.
 * Explore, Experience, Rethink, Revise, Refine, Tailor: Verbal, Logical, Visual, Interpersonal, Intrapersonal, Naturalist, Bodily-Kinesthetic, Musical**

Students will take their IMovie newscast product and self-assess themselves using a given checklist before handing into teacher. The collected graphic organizers will be given positive feedback and handed back. When the students complete their products, they will be graded and returned the following week, if not sooner. The students' blogs that were done at the end of class will be looked at and commented as soon as possible. If the script rough draft was not finished in class, then they will be assigned for homework. Therefore, the students will be well prepared to start their final rough draft and IMovie the next class. This lesson will be the foundation of knowledge for students to know before going on to the next and final lesson that incorporates everything they have learned thus far. <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">
 * Evaluate, Tailor: Intrapersonal, Interpersonal, Visual, Logical, Bodily-Kinesthetic, Naturalist** <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">
 * __<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Content Notes __**<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">

__Plate tectonics of an Earthquake__

T­he biggest scientific breakthrough in the history of **seismology** -- the study of earthquakes -- came in the middle of the 20th century, with the development of the theory of **plate tectoni­cs**. Scientists proposed the idea of plate tectonics to explain a number of peculiar phenomenon on earth, such as the apparent movement of continents over time, the clustering of volcanic activity in certain areas and the presence of huge ridges at the bottom of the ocean. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">earthquake pic || <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">
 * <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">                ||

Hulton Collection/[|Getty Images]
 * The basic theory of plate tectonics is that the surface layer of the earth -- the lithosphere -- is comprised of many plates that slide over the lubricating athenosphere layer.­**

­ The basic theory is that the surface layer of the earth -- the **lithosphere** -- is comprised of many **plates** that slide over the lubricating **athenosphere** layer. At the boundaries between these huge plates of soil and rock, three different things can happen: <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Plates can move apart **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> - If two plates are moving apart from each other, hot, molten rock flows up from the layers of mantle below the lithosphere. This **magma** comes out on the surface (mostly at the bottom of the ocean), where it is called lava. As the lava cools, it hardens to form new lithosphere material, filling in the gap. This is called a **divergent plate boundary**. <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Plates can push together **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> - If the two plates are moving toward each other, one plate typically pushes under the other one. This **subducting** plate sinks into the lower mantle layers, where it melts. At some boundaries where two plates meet, neither plate is in a position to subduct under the other, so they both push against each other to form mountains. The lines where plates push toward each other are called **convergent plate boundaries**. <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Plates slide against each other **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> - At other boundaries, plates simply slide by each other -- one moves north and one moves south, for example. While the plates don't drift directly into each other at these **transform boundaries**, they are pushed tightly together. A great deal of tension builds at the boundary. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Where these plates meet, you'll find **faults** -- breaks in the earth's crust where the blocks of rock on each side are moving in different directions. Earthquakes are much more common along fault lines than they are anywhere else on the planet.

__How an Earthquake Works__

As recently witnessed in China and Iceland, an earthquake is one of the most terrifying phenomena that nature can whip up. We generally think of the ground we stand on as "rock-solid" and completely stable. An earthquake can shatter that perception instantly, and often with extreme violence. Up until relatively recently, scientists only had unsubstantiated guesses as to what actually caused earthquakes. Even today there is still a certain amount of mystery surrounding them, but scientists have a much clearer understanding. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Family members gather at the remains of the collapsed Juyuan middle school, where six children died in Dujiangyan, in southwest China Sichuan province on May 12, 2008. || <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">
 * <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> ||

AFP/AFP/Getty Images
 * Family members gather at the collapsed Juyuan middle school, where six children died in southwest China Sichuan province on May 12, 2008, after an earthquake measuring 7.8 rocked the province. See more** [|**earthquake images**]**.**

There has been enormous progress in the past century: Scientists have identified the forces that cause earthquakes, and developed technology that can tell us an earthquake's magnitude and origin. The next hurdle is to find a way of predicting earthquakes, so they don't catch people by surprise. ­In this article, we'll find out what causes earthquakes, and we'll also find out why they can have such a devastating effect on us. An earthquake is a **vibration** that travels through the earth's crust. Technically, a large truck that rumbles down the street is causing a mini-earthquake, if you feel your house shaking as it goes by, but we tend to think of earthquakes as events that affect a fairly large area, such as an entire city. All kinds of things can cause earthquakes: <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">[|volcanic eruptions] <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">[|meteor] impacts <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">underground explosions (an underground nuclear test, for example) <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">collapsing structures (such as a collapsing mine) <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> __Faults__
 * Shaking Ground­**

Scientists identify four types of faults, characterized by the position of the **fault plane**, the break in the rock and the movement of the two rock blocks: <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">In a **normal fault** (see animation below), the fault plane is nearly vertical. The **hanging wall**, the block of rock positioned above the plane, pushes down across the **footwall**, which is the block of rock below the plane. The footwall, in turn, pushes up against the hanging wall. These faults occur where the crust is being pulled apart, due to the pull of a divergent plate boundary. <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">The fault plane in a **reverse fault** is also nearly vertical, but the hanging wall pushes up and the footwall pushes down. This sort of fault forms where a plate is being compressed. <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">A **thrust fault** moves the same way as a reverse fault, but the fault line is nearly horizontal. In these faults, which are also caused by compression, the rock of the hanging wall is actually pushed up on top of the footwall. This is the sort of fault that occurs in a converging plate boundary. <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">In a **strike-slip fault**, the blocks of rock move in opposite horizontal directions. These faults form when the crust pieces are sliding against each other, as in a transform plate boundary <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">In all of these types of faults, the different blocks of rock push very tightly together, creating a good deal of friction as they move. If this friction level is high enough, the two blocks become **locked** -- the friction keeps them from sliding against each other. When this happens, the forces in the plates continue to push the rock, increasing the pressure applied at the fault. If the pressure increases to a high enough level, then it will overcome the force of the friction, and the blocks will suddenly snap forward. To put it another way, as the tectonic forces push on the "locked" blocks, potential energy builds. When the plates are finally moved, this built-up energy becomes kinetic. Some fault shifts create visible changes at the earth's surface, but other shifts occur in rock well under the surface, and so don't create a surface rupture. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">offset crop rows due to a lateral strike slip fault earthquake in Guatamala || <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> Photo courtesy [|USGS] <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">The initial break that creates a fault, along with these sudden, intense shifts along already formed faults, are the **main sources of earthquakes**. Most earthquakes occur around plate boundaries, because this is where the strain from the plate movements is felt most intensely, creating **fault zones**, groups of interconnected faults. In a fault zone, the release of kinetic energy at one fault may increase the stress -- the potential energy -- in a nearby fault, leading to other earthquakes. This is one of the reasons that several earthquakes may occur in an area in a short period of time. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">shifted railroad tracks due to the earthquake in Guatamala || <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> Photo courtesy [|USGS] <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Every now and then, earthquakes do occur in the middle of plates. In fact, one of the most powerful series of earthquakes ever recorded in the United States occurred in the middle of the North American continental plate. These earthquakes, which shook several states in 1811 and 1812, originated in Missouri. In the 1970s, scientists found the likely source of this earthquake: a 600-million-year-old fault zone buried under many layers of rock. The vibrations of one earthquake in this series were so powerful that they actually rang church bells as far away as Boston! In the next section, we'll examine earthquake vibrations and see how they travel through the ground.
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 * Crop rows offset by a lateral strike slip fault shifting in the 1976 earthquake that shook El Progresso, Guatemala.**
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 * Railroad tracks shifted by the 1976 Guatemala earthquake**

__Seismic Waves__

When a sudden break or shift occurs in the earth's crust, the energy radiates out as **seismic waves**, just as the energy from a disturbance in a body of water radiates out in wave form. In every earthquake, there are several different types of seismic waves. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">structural damage caused by an Alaskan earthquake || <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> Photo courtesy [|USGS] the 1964 Alaska earthquake** There are two main types of body waves. <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Primary waves **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">, also called **P waves** or **compressional waves**, travel about 1 to 5 miles per second (1.6 to 8 kps), depending on the material they're moving through. This speed is greater than the speed of other waves, so P waves arrive first at any surface location. They can travel through solid, liquid and gas, and so will pass completely through the body of the earth. As they travel through rock, the waves move tiny rock particles back and forth -- pushing them apart and then back together -- in line with the direction the wave is traveling. These waves typically arrive at the surface as an abrupt thud. <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Secondary waves **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">, also called **S waves** or **shear waves**, lag a little behind the P waves. As these waves move, they displace rock particles outward, pushing them perpendicular to the path of the waves. This results in the first period of rolling associated with earthquakes. Unlike P waves, S waves don't move straight through the earth. They only travel through solid material, and so are stopped at the liquid layer in the earth's core. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Both sorts of body waves do travel around the earth, however, and can be detected on the opposite side of the planet from the point where the earthquake began. At any given moment, there are a number of very faint seismic waves moving all around the planet. Surface waves are something like the waves in a body of water -- they move the surface of the earth up and down. This generally causes the worst damage because the wave motion rocks the foundations of manmade structures. L waves are the slowest moving of all waves, so the most intense shaking usually comes at the end of an earthquake.
 * || <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> ||
 * Structural damage caused by vibrations from
 * <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Body waves **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> move through the inner part of the earth, while **surface waves** travel over the surface of the earth. Surface waves -- sometimes called long waves, or simply L waves -- are responsible for most of the damage associated with earthquakes, because they cause the most intense vibrations. Surface waves stem from body waves that reach the surface.
 * <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Body waves **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> move through the inner part of the earth, while **surface waves** travel over the surface of the earth. Surface waves -- sometimes called long waves, or simply L waves -- are responsible for most of the damage associated with earthquakes, because they cause the most intense vibrations. Surface waves stem from body waves that reach the surface.

__Seismology__ <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">a shifted fence due to a strike slip fault earthquake in San Fransisco || <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> Photo courtesy [|USGS] <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">We saw in the last section that there are three different types of seismic waves, and that these waves travel at different speeds. While the exact speed of P and S waves varies depending on the composition of the material they're traveling through, the ratio between the speeds of the two waves will remain relatively constant in any earthquake. P waves generally travel 1.7 times faster than S waves. Using this ratio, scientists can calculate the distance between any point on the earth's surface and the earthquake's **focus**, the breaking point where the vibrations originated. They do this with a [|seismograph], a machine that registers the different waves. To find the distance between the seismograph and the focus, scientists also need to know the time the vibrations arrived. With this information, they simply note how much time passed between the arrival of both waves and then check a special chart that tells them the distance the waves must have traveled based on that delay. If you gather this information from three or more points, you can figure out the location of the focus through the process of **trilateration**. Basically, you draw an imaginary sphere around each seismograph location, with the point of measurement as the center and the measured distance (let's call it X) from that point to the focus as the radius. The surface of the circle describes all the points that are X miles away from the seismograph. The focus, then, must be somewhere along this sphere. If you come up with two spheres, based on evidence from two different seismographs, you'll get a two-dimensional circle where they meet. Since the focus must be along the surface of both spheres, all of the possible focus points are located on the circle formed by the intersection of these two spheres. A third sphere will intersect only twice with this circle, giving you two possible focus points. And because the center of each sphere is on the earth's surface, one of these possible points will be in the air, leaving only one logical focus location.
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 * A fence along a strike slip fault that shifted in the 1906 San Francisco earthquake.**

__Richter Scale__

Whenever a major earthquake is in the news, you'll probably hear about its [|Richter Scale] rating. You might also hear about its **Mercalli Scale** rating, though this isn't discussed as often. These two ratings describe the power of the earthquake from two different perspectives. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> Photo courtesy NGDC <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">The Richter Scale is used to rate the **magnitude** of an earthquake -- the amount of energy it released. This is calculated using information gathered by a [|seismograph]. The Richter Scale is **logarithmic**, meaning that whole-number jumps indicate a tenfold increase. In this case, the increase is in wave amplitude. That is, the wave amplitude in a level 6 earthquake is 10 times greater than in a level 5 earthquake, and the amplitude increases 100 times between a level 7 earthquake and a level 9 earthquake. The amount of energy released increases 31.7 times between whole number values. The largest earthquake on record registered an 9.5 on the currently used Richter Scale, though there have certainly been stronger quakes in Earth's history. The majority of earthquakes register less than 3 on the Richter Scale. These tremors, which aren't usually felt by humans, are called **microquakes**. Generally, you won't see much damage from earthquakes that rate below 4 on the Richter Scale. Major earthquakes generally register at 7 or above. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">damage to a school in Anchorage, Alaska due to an earthquake || <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> Photo courtesy [|NGDC] <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Richter ratings only give you a rough idea of the actual impact of an earthquake. As we've seen, an earthquake's destructive power varies depending on the composition of the ground in an area and the design and placement of manmade structures. The extent of damage is rated on the **Mercalli Scale**. Mercalli ratings, which are given as Roman numerals, are based on largely subjective interpretations. A low intensity earthquake, one in which only some people feel the vibration and there is no significant property damage, is rated as a II. The highest rating, a XII, is applied only to earthquakes in which structures are destroyed, the ground is cracked and other natural disasters, such as landslides or Tsunamis, are initiated. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">damage from an earthquake in Niigata, Japan || <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> Photo courtesy [|NGDC] hit Niigata, Japan, in 1964.** <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Richter Scale ratings are determined soon after an earthquake, once scientists can compare the data from different seismograph stations. Mercalli ratings, on the other hand, can't be determined until investigators have had time to talk to many eyewitnesses to find out what occurred during the earthquake. Once they have a good idea of the range of damage, they use the Mercalli criteria to decide on an appropriate rating.
 * Destruction caused by a (Richter) magnitude 6.6 earthquake in Caracas, Venezuela. The 1967 earthquake took 240 lives and caused more than $50 million worth of property damage.** ||
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 * Damage to a school in Anchorage, Alaska, caused by the 1964 Prince William Sound earthquake. The earthquake, which killed 131 people and caused $538 million of property damage, registered an 9.2 on the Richter Scale.**
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 * Damage from a magnitude 7.4 earthquake that

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__Magma/Volcanoes and Plate Tectonics__

The first question this raises is: what exactly is this "material from the inside"? On our planet, it's **magma**, fluid molten rock. This material is partially liquid, partially solid and partially gaseous. To understand where it comes from, we need to consider the structure of planet Earth. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> Graphic courtesy USGS || <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">The earth is composed of many layers, roughly divided into three mega-layers: the **core**, the **mantle** and the **outer crust**: <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">We all live on the rigid outer crust, which is 3 to 6 miles (5 to 10 km) thick under the oceans and 20 to 44 miles (32 to 70)thick under the land. This may seem fairly thick to us, but compared to the rest of the planet, it's very thin -- like the outer skin on an apple. <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Directly under the outer crust is the mantle, the largest layer of the earth. The mantle is extremely hot, but for the most part, it stays in solid form because the pressure deep inside the planet is so great that the material can't melt. In certain circumstances, however, the mantle material does melt, forming magma that makes its way through the outer crust. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">In the 1960s, scientists developed a revolutionary theory called **plate tectonics**. Plate tectonics holds that the **lithosphere**, a layer of rigid material composed of the outer crust and the very top of the mantle, is divided into seven large plates and several more smaller plates. These plates drift very slowly over the mantle below, which is lubricated by a soft layer called the **asthenosphere**. The activity at the boundary between some of these plates is the primary catalyst for magma production. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> Graphic courtesy NASA <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Where the different plates meet, they typically interact in one of four ways: <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">If the two plates are moving away from each other, an **ocean ridge** or **continental ridge** forms, depending on whether the plates meet under the ocean or on land. As the two plates separate, the mantle rock from the asthenosphere layer below flows up into the void between the plates. Because the pressure is not as great at this level, the mantle rock will melt, forming magma. As the magma flows out, it cools, hardening to form new crust. This fills in the gap created by the plates diverging. This sort of magma production is called **spreading center volcanism**. <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">At the point where two plates collide, one plate may be pushed under the other plate, so that it sinks into the mantle. This process, called **subduction**, typically forms a **trench**, a very deep ditch, usually in the ocean floor. As the rigid lithosphere pushes down into the hot, high-pressure mantle, it heats up. Many scientists believe that the sinking lithosphere layer can't melt at this depth, but that the heat and pressure forces the water (the surface water and water from hydrated minerals) out of the plate and into the mantle layer above. The increased water content lowers the melting point of the mantle rock in this wedge, causing it to melt into magma. This sort of magma production is called **subduction zone volcanism**. <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">If the plates collide and neither plate can subduct under the other, the crust material will just "crumple," pushing up mountains. This process does not produce volcanoes. This kind of boundary can develop later into a subduction zone. <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Some plates move against each other rather than push or pull apart. These **transform plate boundaries** rarely produce volcanic activity. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> __How Volcanoes Work__ Whenever there is a major volcanic eruption in the world, you'll­ see a slew of newspaper articles and nightly news stories covering the catastrophe, all stressing a familiar set of words -- violent, raging, awesome. When faced with a spewing volcano, people today share many of the same feelings volcano-observers have had throughout human history: We are in awe of the destructive power of nature, and we are unsettled by the thought that a peaceful mountain can suddenly become an unstoppable destructive force! While scientists have cleared up much of the mystery surrounding volcanoes, our knowledge has not made volcanoes any less amazing. In this article, we'll take a look­ at the powerful, violent forces that create eruptions, and see how these eruptions build volcanic structures like islands. ­When people think of volcanoes, the first image that comes to mind is probably a tall, conical mountain with orange lava spewing out the top. There are certainly many volcanoes of this type. But the term **volcano** actually describes a much wider range of geological phenomena. Generally speaking, a volcano is **any place on a planet where some material from the inside of the planet makes its way through to the planet's surface**. One way is "material spewing from the top of a mountain", but there are other forms as well. Check out the next page to fi­nd out more about magma (that "material spewing") and plate tectonics!
 * The blue lines mark plate boundaries, the red triangles mark active volcanoes and the yellow dots show recent earthquakes.** ||

__Forming Volcanoes__ Magma can also push up under the middle of a lithosphere plate, though this is much less common than magma production around plate boundaries. This **interplate** volcanic activity is caused by unusually hot mantle material forming in the lower mantle and pushing up into the upper mantle. The mantle material, which forms a plume shape that is from 500 to 1000 km wide, wells up to create a **hot spot** under a particular point on the earth. Because of the unusual heat of this mantle material, it melts, forming magma just under the earth's crust. The hot spot itself is stationary; but as a continental plate moves over the spot, the magma will create a string of volcanoes, which die out once they move past the hot spot. The Hawaii volcanoes were created by such a hot spot, which appears to be at least 70 million years old. So what happens to the magma formed by these processes? We saw that the magma produced at ocean ridges just hardens to form new crust material, and so doesn't produce spewing land volcanoes. There are a few continental ridge areas, where the magma does spew out onto land; but most land volcanoes are produced by subduction zone volcanism and hot spot volcanism. When the solid rock changes form to a more liquid rock material, it becomes less dense than the surrounding solid rock. Because of this difference in density, the magma pushes upward with great force (for the same reason the [|helium in a balloon] pushes up through the denser surrounding air and oil pushes upward through denser surrounding water). As it pushes up, its intense heat melts some more rock, adding to the magma mixture. The magma keeps moving through the crust unless its upward pressure is exceeded by the downward pressure of the surrounding solid rock. At this point, the magma collects in **magma chambers** below the surface of the earth. If the magma pressure rises to a high enough level, or a crack opens up in the crust, the molten rock will spew out at the earth's surface. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> Photo courtesy USGS <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">If this happens, the flowing magma (now called **lava**) forms a volcano. The structure of the volcano, and the intensity of the volcanic eruption, is dependent on a number of factors, primarily the composition of the magma. In the next section, we'll look at some different magma types and see how they erupt.
 * Flowing lava on Kilauea Volcano in Hawaii** ||

__Different Shapes and Sizes__

Most land volcanoes have the same basic structure, but volcano shape and size varies considerably. There are several elements that these different volcano types have in common are: <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">a **summit crater** - the mouth of the volcano, where the lava exists <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">a **magma chamber** - where the lava wells up underground <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">a **central vent** - leads from the magma chamber to the summit crater. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">The biggest variation in volcano structure is the **edifice**, the structure surrounding the central vent. The edifice is built up by the volcanic material spewed out when the volcano erupts. Consequently, its composition, shape and structure are all determined by the nature of the volcanic material and the nature of the eruption. The three main volcano shapes are: <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Stratovolcanoes **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">: These are the most familiar type of volcanoes, and generally have the most destructive history of eruptions. They are characterized by a fairly symmetrical mountain edifice, which curves steeply near the relatively small summit crater at the top. They are usually built by Plinian eruptions that launch a great deal of pyroclastic material. As the lava, ash and other material spews out, it rapidly builds the edifice around the vent. Stratovolcanoes tend to have highly infrequent eruptions -- hundreds of years apart -- and typically form in subduction zones. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> Photo courtesy USFWS <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Scoria cone volcanoes **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">: These relatively small cones are the most common volcano type. They are characterized by steep slopes on both sides of the edifice, which lead up to a very wide summit crater. This edifice is composed of ashy tephra, usually spewed out by Strombolian eruptions. Unlike stratovolcanoes, many Scoria cone volcanoes have only one eruption event. <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> Photo courtesy USGS <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> <span style="font-size: 10pt; color: black; font-family: Symbol; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol;"> ·  **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">Shield volcanoes **<span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';">: These wide, relatively short volcanoes occur when low-viscosity lava flows out with minimal explosiveness, such as in Hawaiian eruptions. The lava disperses out over a wide surface area -- sometimes hundreds of kilometers -- building up a shield-shaped dome. Near the summit, the edifice gets a little steeper, giving the volcano a slightly raised center. Many shield volcanoes erupt with great frequency (every few years or so). <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> Photo courtesy USGS <span style="font-size: 12pt; color: black; font-family: 'Times New Roman','serif';"> Source: []
 * Kanaga Volcano, a stratovolcano in Alaska** ||
 * Sunset Crater, a scoria cone volcano in Arizona** ||
 * Mauna Loa, a shield volcano in Hawaii.** ||

Checklist Graphic Organizer (Four-Column Chart) <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';"> **__<span style="font-size: 20pt; font-family: 'Times New Roman','serif';">Checklist for Comic Life __** <span style="font-size: 20pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 20pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 20pt; font-family: 'Times New Roman','serif';">1.) ___ Graphic Organizer has been filled out <span style="font-size: 20pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 20pt; font-family: 'Times New Roman','serif';">2.) ___ Shared ideas with class (Think-Pair-Share) <span style="font-size: 20pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 20pt; font-family: 'Times New Roman','serif';">3.) ___ There are three different types (boundary zones) that are specified in movie <span style="font-size: 20pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 20pt; font-family: 'Times New Roman','serif';">4.) ___ Graphic Organizer has positive feedback on it <span style="font-size: 20pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 20pt; font-family: 'Times New Roman','serif';">5.) ___ Students have an IMovie script (rough draft) <span style="font-size: 20pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 20pt; font-family: 'Times New Roman','serif';">6.) ___ Students have an IMovie script (final draft) <span style="font-size: 20pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 20pt; font-family: 'Times New Roman','serif';">7.) ___ IMovie is entertaining, organized, grammatically correct, handed in on time, and finished. <span style="font-size: 20pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 20pt; font-family: 'Times New Roman','serif';">8.) ___ Blog entries were maintained <span style="font-size: 20pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 20pt; font-family: 'Times New Roman','serif';">9.) ___ Now give yourself a pat on the back! Great job! <span style="font-size: 20pt; font-family: 'Times New Roman','serif';"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">
 * Handouts**
 * <span style="font-size: 12pt; font-family: 'Times New Roman','serif';">Reflection: **
 * <span style="font-size: 20pt; font-family: 'Times New Roman','serif';">~*You Must Complete the Following*~ **