RESEARCH/DATA

MEMORIES OF THE SAN FRANCISCO EARTHQUAKE

        Shortly after five in the morning, on April 18, 1906 DeWitt C. Baldwin woke up to practice the piano.  It was about 5:15 A.M., and he had got as far as sitting up with his feet over the bed when unexpectedly the house began shaking violently.  He heard dishes break from different parts of the house and the furniture moved at the violence of the shock.

        He quickly ran down the hall to see the effects of the earthquake, for he was only eight years old.  He was excited so he stayed at the window.  Outside DeWitt noticed people running up and down the street while others like him were curiously looking out their windows.  They all went to get dressed.  Afterwards, while they were eating breakfast around 7:45 A.M., the second strong earthquake hit.  Shortly after the second earthquake hit, he heard sirens wailing all over the city.  This indicated that local fires had started.  After the tremors stopped, he rushed outdoors.  As he was running to see the nearest fire, he came across a small three story hotel that evidently had been built over a subterranean fault line.  The first story had partly sank in the earth while the second and third had fallen out into the street.

       DeWitt then came across a huge crowd watching a huge department store ablaze.  He was observing how the firemen were desperately trying to control it.  After surveilling some time and listening to tales from different folks who were there to see the fire, he turned to go back home and on the way he collected information about other fires from distant places in the city.  Many people returned home, got their valuable possessions and clothes and headed for the mountains.  As the day continued he saw many things that were amusing and entertaining.  He saw gaps on the ground that were as wide as 5 feet and as deep as 25 feet.  On the third day, many fires were still in progress, and many structures in our neighborhood were destroyed and leveled to the ground.

        Later that day they were ordered to leave their homes and find shelter in the hills, because the flames would soon reach their home.  In the middle of the fourth day someone informed them that they were going to dynamite the houses so it would be difficult for the flames to spread across the street.  The fire was controlled on 20th St. so anyone who lived beyond that point could return home if they wanted to.

        A few weeks later when the reconstruction began, he moved to a summer cottaage in Larkspur, so he hardly had any time with his parents because they were so busy.  He was not in the city during the reconstruction period.                                                                                                                                Jessica

Duck, cover, and hold

THE EARTHQUAKE GAME

When someone calls "earthquake," everyone must pretend that an earthquake is happening and "duck, cover, and hold." After 15 seconds, you come out and take five slow breaths to practice calming down. Then discuss how everyone responded and what could be done better.

Pay close attention to what you feel during a real earthquake, and you can estimate its magnitude and location. First, you need to know: 1) earthquakes produce two types of waves, P and S. The S-wave arrives later but is bigger, 2) rapid shaking dies off quickly with distance so nearby earthquakes are "jolting" and far away earthquakes are "rolling," and 3) the time duration of the earthquake increases with the magnitude.

During an earthquake, try to recognize the two waves. The distance to the earthquake is the time between them times 5 miles per second. Count how long the ground moves strongly in the S wave (don't wait for every jitter to die away). Use the table on page 23 to estimate the magnitude from the duration of the earthquake shaking. You will then have an idea of the magnitude and distance to the earthquake before you get out from under the table.

 

A SPECIAL NOTE ABOUT CHILDREN

If earthquakes scare us because we feel out of control, think how much more true this must be for children, who already must depend on adults for so much in their lives. It is important to spend time with children in your care before the next earthquake to explain why earthquakes occur, involve them in hazard hunts (page 11), prepare earthquake bags, and practice "duck, cover, and hold." Play the Earthquake Game. Consider simulating post-earthquake conditions by going without electricity or tap water.

After the earthquake, remember that children will be under great stress. They may be frightened, their routine will be disrupted, and the aftershocks won't let them forget. Expect their behavior to regress. Adults tend to leave children to deal with the many demands of the emergency, but this can be devastating to children. Extra contact and support from parents in the early days will pay off later. Whenever possible, include children in the recovery process.

 

COMMON EARTHQUAKE MYTHS

DON'T BE FOOLED BY THE TOP FIVE MYTHS!

MYTH #1

"Big earthquakes always happen in the early morning."

This myth may be so common because we want it to be true. Several recent damaging earthquakes have been in the early morning, so many people believe that all big earthquakes happen then. In fact, earthquakes occur at all times of day. The 1933 Long Beach earthquake was at 5:54 p.m. and the 1940 Imperial Valley event was at 9:36 p.m. Even recently, the 1990 Upland earthquake was at 3:43 p.m. and the 1989 Loma Prieta event was at 5:02 p.m. It is easy to notice the earthquakes that fit the pattern and forget the ones that don't.

MYTH #2

"It's hot and dry--earthquake weather!"

Many people believe that earthquakes are more common in certain kinds of weather. In fact, no correlation with weather has been found. Earthquakes beginmany kilometers below the region affected by surface weather. People tend to notice earthquakes that fit the pattern and forget the ones that don't. Also, every region of the world has a story about earthquake weather, but the type ofweather is whatever they had for their most memorable earthquake.

MYTH #3

"Beachfront property in Arizona"
The idea of California falling into the ocean has had an enduring appeal to those envious of life in the Golden State. Of course, the ocean is not a great hole into which California can fall, but it is itself land at a somewhat lower elevation with water above it. The motion of plates will not make California sink--California is moving horizontally along the San Andreas fault and up around the Transverse Ranges.

MYTH #4

"We have good building codes so we must have good buildings."

The tragedy in Kobe, Japan, one year after the Northridge earthquake, painfully reminds us that the best building codes in the world do nothing for buildings built before that code was enacted. Fixing problems in older buildings--retrofitting --is the responsibility of the building's owner.

MYTH #5

"Head for the doorway"

An enduring earthquake image of California is a collapsed adobe home with the door frame as the only standing part. From this came our belief that a doorway is the safest place to be during an earthquake. True--if you live in an old, unreinforced adobe house. In modern houses, doorways are no stronger than any other part of the house and usually have doors that will swing and can injure you. You are safer under a table.

SAFETY
PLANS

            We need a safety plan to save as many lives as possible.  When an earthquake occurs it causes a lot of destruction.  For example, a survivor of April 18, 1906 stated, "All I  saw were fire fighters, police officers and many more helpers to the rescue.  "Earthquakes can cause a fire all over a town or city.  The earthquake of 1906 proved this.  DeWitt C. Baldwin stated, "There were 53 different fires all over the city."  Today you can still see earthquakes start fires, and even make buildings collapse.  With a safety plan we are able to get out of burning and falling buildings alive.  For example, in 1906 a three story hotel sank into the ground.  Plans were needed to escape this disaster.  There can be a tiny shake or a tremendous shake.  That is why we need a plan. 

        In a time of a disaster, we need to make sure that we're safe and everyone around us is safe.  So,  join me in helping all of you.  Start rally's and help our community be safe for you and me.                                                                            Andrea

 

WHAT IS YOUR SAFETY PLAN?

        Many people already have a safety plan, but do you?  Well, if you don't you should use this safety precaution:  Use a large container such as a footlocker or 30-gallon trash can, and label each food and water item with the date of purchase or the last date it should be used.  Place the container in a cool, dark place, such as a garage, on something to raise it off the ground.

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MIDDLE

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PLATE TECTONICS

Plate Tectonics is the theory of the plates upon which the continents sit.  These plates move, rub and push against each other.  The movement of the plates occur along the edges of the plates where the most force is at work.  There are four types of plate boundaries, which are:

                                                                                        Felipe

Divergent Boundaries are formed when two plates move away from each other and the space left between them is now taken up by a new crust formed by magma pushing up from the mantle.

                                                                Plate Boundary Zone:  One of these zones marks the Mediterranean area between the Eurasian Plate and the African Plate.

 

 

Felipe

 

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