Catastrophic Events Project!

We are rapidly finishing up our unit on catastrophic events. To show off what you have learned you will be choosing one project from a choice board. All projects are to be done by Dec 2 for full credit. Also, this is an independent project. I am available after school for one on one help. Please see the side bar for links to choices, rubrics and websites.

Looking at earthquakes

Up to this point, we have focused on what earthquakes are, how we detect them and how they are measured. Now we are going to start trying to answer that nagging question that everyone keeps asking - Why do they happen?

To answer this question we need to understand where they occur. In class today we discovered that there are patterns in their locations, but not always. We also highlighted the 3 major belts for seismic activity: Ring of Fire, Mid- Atlantic Ridge, and the Mediterranean-Himalyan Belt.

Tomorrow, we are going to work on how the plate tectonic theory all came about.

HOMEWORK! Complete the questions using your plate boundary map

Measuring earthquakes

Seismologists assign values for the amount of energy and the damage caused during an earthquake. We use the term magnitude to describe the energy and intensity to describe the observations that are seen or felt. Magnitude is measured using the Richter scale and intensity is measured using the Modified Mercalli scale. In class today we used the scale to assign a value based on observations from 28 cities. Once that was completed we were able to locate the zone for each value by encircling the towns for each value.

Homework!  Use your map on pg 23 to write your summary on pg 22. Be sure to answer the following questions in your summary:



• What cities were closest to the epicenter of the earthquake?


• Approximately how wide was the zone with a rating of a V or higher?


• How were you able to determine all of this? (What did you do?)


• Discuss some possible sources of error when working with the Mercalli scale to locate the epicenter of an earthquake.

Recording seismic data

Last week we investigated how a seismograoh works and how to read a seismogram. Today we wrapped up our lesson by looking at how seismologist use this data to find the epicenter.

Most damage during an earthquake comes from structures affected by the shaking. We discussed improvements that could be made in our classroom to minimize damage and keep us safe. BONUS!! On a separate piece of paper complete a safety check of your house. Choose one room or the whole thign- tell me what improvements you could make to keep damage to a minimum. This is an optional homework

Homework (everyone is to complete): Study guide questions for test on Wednesday, October 5. This page will go in your notebook on pg 19.

Seismic waves

Last week we used slinkies to mimic earthquake waves. Today, we discussed our findings from the investigation. Seismic waves travel outward in all directions. After the earth moves energy is released in a series of waves- P, S and surface waves. We also discussed arrival times, where they occur, how they move and the damage they cause. All of this should be written onto pg 14 in your ISN.

There will be a quiz Wednesday. Study pages 14 and 15 in your ISN.

Shake, rattle and roll!

I can now check off "feel an earthquake" from my "to do" list! I was sitting on the beach when the earth started to move.  It was definitely a strange experience.

Were you able to feel it? Luckily earthquakes are one of our topics of study this year so we will have plenty to talk about. Don'y worry too much, though. Earthquakes this strong along the East Coast are not that common.

Finding the epicenter

Some math is involved when trying to locate the epicenter. Today our focus was on calculating the "lag time" of the P and S-waves. We then used this info to find the distance on the time-distance graph.

Homework tonight! Complete Parts 1 and 2 on the Time Travel worksheet. I will help you with Part 3 in class.

Also trip money/slip was due today. If you did not turn it in and would like to go with us on 10/20 please see me!!!

Seismograph variables

We completed Inquiry 12.1 today in class. A sesimograph gives us three things: direction, amplitude, and force. But, we need more than one type to get accurate seismic data.

Have a great weekend!

Earthquake triggers a tsunami

Two strong earthquakes have happened within the past day.

1. Under the ocean floor near the Samoa Islands (Pacific Ocean)
1. 8.0 magnitude
2. This triggered a tsunami that reached the island of the American Samoas
2. In Indonesia, near Sumatra
1. 7.6 magnitude
2. Tsunami warnings were issued but cancelled.

These are not the only earthquakes that have occurred. Check out the USGS site to see just how many quakes rattle the ground each day.

Earthquake engineering

This week our focus is on how to reduce the amount of damage caused from an earthquake.

Remember~ It is not the earthquake itself that causes all the destruction. The destruction is a result of what can happen when the earth shakes.

Today we acted as insurance adjusters and assessed damage to various property during the 1906 quake in San Francisco.

Tomorrow, we will start looking at how buildings are constructed and what can be done to make them safer.

Thursday you will then be the engineers ~ constructing a building that can withstand an earthquake. Paying attention in class this week will definitely come in handy for this!

Homework tonight!! Read pgs 130-133 and complete questions on handout.

Also be sure to review your notes on Lessons 10 and 11 ~ You have a quiz on Friday!

Finally Friday!

We discussed our findings on earthquake waves:

• P-waves (Primary waves) are the fastest and first to travel during a quake
• S-waves (Secondary waves) come after the p-waves
• Surface waves arrive last and cause the most destruction

**BONUS** Can you tell me what name(s) seismologists call surface waves? If so, bring your answer into class on Tuesday!

Be sure to study your Lesson 10 and 11 notes  for a quiz on Friday, October 2.

Hope you enjoy the 3-day weekend!

Body waves

You may not have figured out which is fastest but you should know how the 2 waves move.

• P-waves ~ push and pull through the earth
• S-waves ~ move side to side through the earth

Tomorrow, we will share our data with the class and determine which waves travel the fastest.

To be completed for class tomorrow:

• All parts of Student Sheet 11.1
• Answer all reflection questions on page 127
• On a piece of paper, write a GOOD conclusion about what you have learned during this investigation.
• Use that small piece of paper that you taped into your binder to help you!

Thinking about earthquakes

Today marks the first day of our unit on earthquakes. During the unit we will investigate (and be able to explain!) all the whys, hows and wheres we have about earthquakes.

To get us thinking we started off by viewing the video The Day the Earth Shook. First, we gathered some info so we could compare the 2 quakes. One interesting fact was the quakes occurred exactly a year a part (even the time was close). Tomorrow, we will look at how seismologists analyzed the data from those 2 quakes and what was learned from the data.

Remember ~ leave your textbook at home!