When an earthquake occurs, two types of sound waves are generated and travel through the earth. The primary, or P, wave has a speed of about 10.5 km/s and the secondary, or S, wave has a speed of about 5.5 km/s. A seismograph, located some distance away, records the arrival of the P wave and then, 140 s later, records the arrival of the S wave. Assuming that the waves travel in a straight line, how far is the seismograph from the earthquake?

Technorati Tags: earth, earthquake, s wave, seismograph, straight line, types of sound waves

i get that like they detect vibrations but do scientist set up sensors around the earth? how else could the machine detect earthquakes all over the world?

Technorati Tags: earth, earthquakes, scientist, sensors

A) The epicenter is calculated after the all the aftershocks of an earthquake are plotted. It is the statistical center of the earthquake. The focus is the spot of first motion of the rocks.
B) The epicenter is where the energy is first released and the focus of the earthquake is where most of the damage is done
C) The focus of the earthquake is were surface waves are first detected while the epicenter is where the P and S waves are detected.
D) The epicenter is the spot on the Earth’s surface directly above the focus.

Technorati Tags: aftershocks, earth, earthquake, epicenter, rocks, s waves, statistical center, surface waves

Following Hurricane Katrina in 2005, there became a strong concern in this country
about our ability to cope with natural disasters. Due to the expensive cost of
acquiring detailed data about the hazard before, during and after the event, many
agencies are putting systems forth to allow citizens affected by the events to
contribute details about their surroundings. This may be in the form of data sent
over a mobile phone, or Internet connection to a PC. Please weigh in your thoughts
about using this system as a method of coping with natural disasters by taking this
brief survey.
* 1. Have you ever experienced a natural disaster?
Yes
No
2.
Which of the following hazards have you experienced?
Flood
Hurricane
Earthquake
Fire
Tornado
None
3.
About at what intensity did the disaster occur?
Very low
low
moderate
high
very high
* 4.
Did you have access to the internet following the event
Yes
No
5.
As the event passed, did you feel that adequate updates about the hazard were
provided to affected citizens?
Yes
No
* 6.
Following the event, did you feel coherent enough that you would be able to
communicate in detail about your surroundings?
Yes
No
* 7.
Have you ever contributed Geospatial Information about a hazard or extreme event
online? (Through Google Earth, USGS website, Weather channel, etc..)
Yes
No
* 8.
Do you have any experience using a GPS system?
Yes
No
* 9.
Do you feel that your community has an adequate emergency response system in
place for the onset of natural disasters?
Yes
No
10.
Do you feel that GIS and Remote Sensing is a very appropriate way of coping with a
natural disaster before, during and after the onset of a natural hazard
Yes
No

Technorati Tags: citizens, earth, earthquake, emergency response system, extreme event, flood, google, gps system, hurricane katrina, intensity, internet connection, mobile phone, natural disaster, natural disasters, natural hazard, remote sensing, surroundings, Tornado, weather channel

Following Hurricane Katrina in 2005, there became a strong concern in this country
about our ability to cope with natural disasters. Due to the expensive cost of
acquiring detailed data about the hazard before, during and after the event, many
agencies are putting systems forth to allow citizens affected by the events to
contribute details about their surroundings. This may be in the form of data sent
over a mobile phone, or Internet connection to a PC. Please weigh in your thoughts
about using this system as a method of coping with natural disasters by taking this
brief survey.

* 1. Have you ever experienced a natural disaster?
Yes
No
2.
Which of the following hazards have you experienced?
Flood
Hurricane
Earthquake
Fire
Tornado
None
3.
About at what intensity did the disaster occur?
Very low
low
moderate
high
very high
* 4.
Did you have access to the internet following the event
Yes
No
5.
As the event passed, did you feel that adequate updates about the hazard were
provided to affected citizens?
Yes
No
* 6.
Following the event, did you feel coherent enough that you would be able to
communicate in detail about your surroundings?
Yes
No
* 7.
Have you ever contributed Geospatial Information about a hazard or extreme event
online? (Through Google Earth, USGS website, Weather channel, etc..)
Yes
No
* 8.
Do you have any experience using a GPS system?
Yes
No
* 9.
Do you feel that your community has an adequate emergency response system in
place for the onset of natural disasters?
Yes
No
10.
Do you feel that GIS and Remote Sensing is a very appropriate way of coping with a
natural disaster before, during and after the onset of a natural hazard
Yes
No

What state are you located in?

Technorati Tags: citizens, earth, earthquake, emergency response system, extreme event, flood, google, gps system, hurricane katrina, intensity, internet connection, mobile phone, natural disaster, natural disasters, natural hazard, remote sensing, surroundings, Tornado, weather channel

we were give a puzzle problem to solve and here it is..

"And the Earth Moved"
Seismographs are sensitive instrument for detecting earthquakes. They consists of large mass suspended by springs. When an earthquake happens, the disturbance travels through the earth, making the instrument vibrate. However, the mass tends not to move because of its inertia. This difference in movement is simplified and written out as a trace.

can you explain why most places in the world receive two traces for each single earthquake event? Can you also explain why a few places detect only one?

Thanks in advance

Technorati Tags: earth, earthquake, earthquakes, inertia, places in the world, puzzle, seismographs, sensitive instrument, thanks in advance, traces

Following Hurricane Katrina in 2005, there became a strong concern in this country
about our ability to cope with natural disasters. Due to the expensive cost of
acquiring detailed data about the hazard before, during and after the event, many
agencies are putting systems forth to allow citizens affected by the events to
contribute details about their surroundings. This may be in the form of data sent
over a mobile phone, or Internet connection to a PC. Please weigh in your thoughts
about using this system as a method of coping with natural disasters by taking this
brief survey.

* 1. Have you ever experienced a natural disaster?
Yes
No
2.
Which of the following hazards have you experienced?
Flood
Hurricane
Earthquake
Fire
Tornado
None
3.
About at what intensity did the disaster occur?
Very low
low
moderate
high
very high
* 4.
Did you have access to the internet following the event
Yes
No
5.
As the event passed, did you feel that adequate updates about the hazard were
provided to affected citizens?
Yes
No
* 6.
Following the event, did you feel coherent enough that you would be able to
communicate in detail about your surroundings?
Yes
No
* 7.
Have you ever contributed Geospatial Information about a hazard or extreme event
online? (Through Google Earth, USGS website, Weather channel, etc..)
Yes
No
* 8.
Do you have any experience using a GPS system?
Yes
No
* 9.
Do you feel that your community has an adequate emergency response system in
place for the onset of natural disasters?
Yes
No
10.
Do you feel that GIS and Remote Sensing is a very appropriate way of coping with a
natural disaster before, during and after the onset of a natural hazard
Yes
No

What state are you located in?

Thank you for your contribution

Technorati Tags: citizens, earth, earthquake, emergency response system, extreme event, flood, google, gps system, hurricane katrina, intensity, internet connection, mobile phone, natural disaster, natural disasters, natural hazard, remote sensing, surroundings, Tornado, weather channel

* 1. Have you ever experienced a natural disaster?
Yes
No
2.
Which of the following hazards have you experienced?
Flood
Hurricane
Earthquake
Fire
Tornado
None
3.
About at what intensity did the disaster occur?
Very low
low
moderate
high
very high
* 4.
Did you have access to the internet following the event
Yes
No
5.
As the event passed, did you feel that adequate updates about the hazard were
provided to affected citizens?
Yes
No
* 6.
Following the event, did you feel coherent enough that you would be able to
communicate in detail about your surroundings?
Yes
No
* 7.
Have you ever contributed Geospatial Information about a hazard or extreme event
online? (Through Google Earth, USGS website, Weather channel, etc..)
Yes
No
* 8.
Do you have any experience using a GPS system?
Yes
No
* 9.
Do you feel that your community has an adequate emergency response system in
place for the onset of natural disasters?
Yes
No
10.
Do you feel that GIS and Remote Sensing is a very appropriate way of coping with a
natural disaster before, during and after the onset of a natural hazard
Yes
No

What state are you located in?

Thank you for your contribution

Technorati Tags: citizens, earth, earthquake, emergency response system, extreme event, flood, google, gps system, Hurricane, intensity, natural disaster, natural disasters, natural hazard, remote sensing, surroundings, Tornado, weather channel

I heard about this but I’m not sure how they have an impact on the Earth’s axial rotation. They said these earthquakes cause the Earth to speed up in axial rotation and there was one today; I hope to God and in my heart, no innocent people were caught in it. That would be bad. Would we have to skip a second or make them internally shorter on the other hand?

Technorati Tags: earth, earthquakes, god, heart

how and why the behavior of seismic body waves changes at the different boundaries within
the Earth (refraction, reflection).

Technorati Tags: boundaries, earth, reflection, refraction, seismic body waves

soooooooooooo…. they said we have nothing to worry about… with all the hype of the obvious "2012" thing, but more specifically, the fact that the earth is going through a lot more the past few years is pretty bad.

tell me this doesn’t add up to something?

http://news.yahoo.com/s/space/20100609/sc_space/moreactivesunmeansnastysolarstormsahead

http://earthquake.usgs.gov/earthquakes/eqarchives/year/eqstats.php

-note- the stats aren’t as high as past years, but this year isn’t even half way over and already it’s above half the other years.

http://hogueprophecy.com/2010/natural-disasters-the-quickening-in-2010/

another thing – the chile earthquake shifted the earth’s axis, and our days are shorter by a fraction of a second, i know not to worry about a fraction of a second, but eventually it adds up… 1/50th of a second is a whole second in just 50 days, a minute in a couple years, and will eventually add up to an hour to a whole day to a couple days, to a week, to a month, to a couple months to half a year, to a whole year (that’s giving the half a second or whatever it is, hundreds of years to take away a whole years worth of time)… i plan on living a long healthy life, so why would i want a day or two taken out of my routine?

no, i’m not being paranoid… frankly, i don’t give a crap. i just wanted to post a question to make people think. SO please don’t put up "omg you’re so dumb" "wow you need to kill yourself" "wtf you believe everything you read" answers.

ten points will go to the person who puts the most thought into their answer… thus, you won’t get 10 points by posting "posting for points" because that’s not going to get you anywhere.
i applaud you dylan, although, you’re a dick… so i have to give you a thumbs down.
gexi… i’ll be with you in hell because i don’t believe in it either LOL and i don’t think the world is gonna end ^^ i’m not into following the rest of the obvious cattle into the cage so we can be slaughtered. but, i don’t believe nothing is going to happen.. i’d rather be undecided because that way whatever happens happens and i can accept it either way.

Technorati Tags: axis, cattle, chile earthquake, couple days, crap, dick, earth, earthquakes, fraction, hell, hundreds of years, hype, lol, natural disasters, news yahoo, omg, quot, wtf, yahoo

I’m writing a research paper and I need to know how far from the earth’s crust the epicenter of the earthquake in Chile. Anyone have any idea? If you have a website that says it could you give me the link too so I can site my sources?

Technorati Tags: earth, earthquake in chile, epicenter of the earthquake, writing a research paper

Geologists say that there’s gonna be a Mega earthquake in Southern California very soon since there hasn’t been one since the 1700′s now.. they say that tension in the earth’s crust is rising and that the consequences qould be a total devastation of LA and San Francisco. Do you think its true?

Technorati Tags: consequences, earth, earthquake in southern california, geologists, san francisco, tension, total devastation

Where on earth has the most earthquakes and volcanic eruptions?

Technorati Tags: earth, earthquakes, volcanic eruptions

Wake Up!……. For Jesus Christ specially said that “earthquakes in one place after another” would mark “the conclusion of the system of things.”—Matt. 24:3, 7.

If a picture is worth a Thousand Words… Please take Note

http://www.thehorizonproject.com/earthquakes.cfm

This Final Witness Work Has to be Completed also….so no one can say "No one tried , To Witness to Me"

(Matthew 24:14) And this good news of the kingdom will be preached in all the inhabited earth for a witness to all the nations; and then the end will come.

Jesus Christ the Faithful Witness Says: . . .Look! I am standing at the door and knocking. If anyone hears my voice and opens the door, I will come into his [house] and take the evening meal (Last Days?) with him and he with me. . .(Revelation 3:20)
(Matthew 24:36-42) 36 “Concerning that day and hour nobody knows, neither the angels of the heavens nor the Son, but only the Father. 37 For just as the days of Noah were, so the presence of the Son of man will be. 38 For as they were in those days before the flood, eating and drinking, men marrying and women being given in marriage, until the day that Noah entered into the ark; 39 and they took no note until the flood came and swept them all away, so the presence of the Son of man will be.

Technorati Tags: angels, conclusion, earth, earthquakes, faithful witness, final witness, flood, jesus christ, last days, marriage, matthew 24, noah, presence, revelation, son of man

Earthquakes produce two kinds of seismicwaves: he longitudinal primary waves (called P waves) and the transverse secondary waves (called S waves). Both S waves and P waves travel through Earth’s crust and mantle, but at different speeds; the P waves are always faster than the S waves, but their exact speeds depend on depth and location. For the purpose of this exercise, we assume the P wave’s speed to be 8480 m/s while the S waves travel at a slower speed of 4510 m/s.If a seismic station detects a P wave and then 67.2 s later detects an S wave, how far away is the earthquake center? Answer in units of km.

Technorati Tags: earth, earthquake center, earthquakes, exercise, mantle, primary waves, s wave, s waves, secondary waves, seismic station, two kinds

Okay, there have been a lot of earthquakes recently: a small on in Chicago, the one in Haiti, one in Chile, one in Mexico and one near Tibet, and now there’s volcanic activity in Iceland, which is basically a little chunk of land on a fault line. All of the earthquakes except for the 2.5 one in
Chicago have been above 7.0 in magnitude. Does this mean something’s going on with the earth’s crust?

Technorati Tags: chile, chunk, earth, earthquakes, fault line, haiti, magnitude, mexico, tibet, volcanic activity

as of late would this mean that the Earth is under pressure internally and needs to release the pressure being heated up over time which in turn would make the Earth’s surface warmer also ? Any links to studies on this matter ? Just curious.
After reading what i typed i meant all the volcanoes erupting lately and if there is a correlation to the Earth heating up. Sorry about that, lol.
Thx Trevor
Thx Antarcticice for the informative link.

Technorati Tags: correlation, earth, informative link, lol, volcanoes

Not just the earthquakes and volcanoes but what about theses lights falling from the sky and all these comets appearing in the night sky this year? It’s like Earth gone wild 2010 edition. I am not feeding for conspiracies,if some one has a deep educational explanation I want to know.

If you want to know what I talking about,with the lights and comets falling

http://www.youtube.com/watch?v=EC5qtaD9qb0&feature=related

If you want to see the list seismic activity that has happened with year

http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/quakes_all.php

Technorati Tags: amp, comets, conspiracies, earth, earthquake, earthquakes and volcanoes, falling from the sky, night sky, quakes, seismic activity, theses

have the earth always been quaking?

http://earthquakescanada.nrcan.gc.ca/index-eng.php

http://earthquake.usgs.gov/

Technorati Tags: ca index, earth, earthquake, index eng, nrcan

Thus far, I am underwhelmed with the light quality and quantity generated by these new bulbs, and I feel sure that the mercury is going to contaminate the earth in ways we can’t even imagine, affecting the safety of food crops and water used for bathing, drinking, fish in the ocean…on and on.
Some of ya’ll may have never had an old-style glass thermometer. When those would break, the mercury is the weirdest most out of control stuff to clean up, but as a child, when I saw those little balls rolling across the floor, it was natural to want to play with something. As natural as a kid wanting to play with potato/sow/roly poly bugs Consider the people who clean up after earthquake damage, house fires. Consider the cleaning lady who cleans up after a wild frat party w/Broken Stuff everywhere. Life is messy. You can’t contain all that mercury because Accidents and Life are not neat and tidy.
I think the new light bulbs are just the latest Green Fashion.

Technorati Tags: accidents, balls, cleaning lady, earth, earthquake damage, fashion, fish, food crops, glass thermometer, house fires, light bulbs, light quality, mercury, old style, roly poly bugs, wild frat party

ANOTHER earthquake In Turkey

I know that the Earth is constantly having earthquakes here and there but i’m talking about the ones that killed LOADS of people the past few months.

Wasn’t there an earthquake in Taiwan LAST WEEK?

WTF

R.I.P to all the people that have lost their lives.

Can someone give me a scientific answer?

Technorati Tags: earth, earthquake in taiwan, earthquake in turkey, earthquakes

whats the point of building and underground home if there will be earthquakes and other natural disasters? wont it be worst because the ground will crack open and you will suffocate?
when the earth cracks open, the dirt will cover the underground home.. it sounds safer on the top of the ground than the bottom to me.. but what do you think?

Technorati Tags: cracks, dirt, earth, earthquakes, natural disasters, underground home

Lately, I have been thinking more and more about the possibility of a doomsday event happening in 2012. Theories such as Nibiru/Planet X is a lie, as I know it is not possible.
What about the event of a super volcano such as the one under Yellow Stone Park? The Earth has been having bad earthquakes of late, maybe its a sign?
I am interested in the Nemesis theory however, is it possible our Sun could have a companion star?
Post your thoughts.

Technorati Tags: companion star, doomsday, earth, earthquakes, nemesis, planet x, stone park, sun, super volcano, yellow stone park

so ive been thinking, and ive had an idea. i just wanted it to get to you guys. i don’t believe the world will end in 2012, but ive been seeing HOW it COULD happen.
i would first like to point this out; an earthquake struck haiti, a place already struggling.
one month later: an even bigger earthquake struck. not only is this earthquake bringing tsunamis to other countries, it also so happens that the earths rotation has been changed and our day has become shorter. i don’t know about you guys, but when i heard that there was an earthquake powerful enough to change the earth’s natural course, i felt that this is a power that only a catastrophic event could exceed. think about it: a 2012 disaster would have that kind of effect, and possibly worse. do you guys understand?
what else could end the world?
oh yeah, almost forgot that some very unfriendly people in North Korea are ignoring pleads from other countries and are deciding to go on with their nuclear bomb programs. yeah, i find it very possible that north korea could start a nuclear war or just bomb its enemies.
oh yeah, iran is gaining radioactive elements, right? or some country in the middle east, i cant remember…
what else could destroy the world/human civilization?
i heard about this thing called global warming. just a little thing, really, unless the ice caps melt. if that happens, guess what? its been calculated that cities like New York with their huge sky scrapers would be thousands of feet under water.
if i can remember correctly, earthquakes starting up, the ice caps melting, and a nuclear war would kill us all. and it would fit the mayan prophecy of the end of the world.
i don’t really believe the world will end, but i think that its possible, and with the latest events, that possibility is getting even bigger.

Technorati Tags: caps, catastrophic event, Disaster, earth, earthquake, earthquakes, earths rotation, enemies, global warming, haiti, human civilization, iran, mayan prophecy, middle east, north korea, nuclear bomb, nuclear war, radioactive elements, sky, tsunamis

WHY?
is it cause they Know Planete X is getting closer to the earth?

Technorati Tags: earth

I’m personally afraid of what’s happening now, Haiti’s earthquake, Chile’s earthquake I don’t know what’s going to happen next, i know I’m not suppose to know, but what if it gets worse, I’m really worried about how the earth is behaving and now because of the latest earthquake the days are shorter, and the 2012 is closer and everything is so connected do you think that maybe the end of our world is actually coming closer? Just tell me your opinion, and no mean comments Thanks!

Technorati Tags: chile, earth, earthquake, haiti

When Jupiter will no longer protect earth from asteroids.

Technorati Tags: asteroids, earth, jupiter

10? 11? 12? Also will it cause major canyon size cracks on earth and make Vegas beach front property like the movie 2012 depicted devouring everything?

Is there a maximum magnitude earthquake you can have? Can you have magnitude 20 or above?
I posted question here cause I didn’t get any answer in the geology forum & since military people know everything.
Oh yeah, Haiti!

Technorati Tags: amp, cracks, earth, geology forum, haiti, magnitude earthquake, major canyon, maximum magnitude

Presently I am living in Sikkim since last about 20 years and it has been observed that in the Himalayan Region, as well as in other parts of the earth, most earthquakes occurs at late night or in the early morning.

In the last 20 years only once I have noticed earthquake at 11 AM approx. WHY SO?

Technorati Tags: earth, earthquake, earthquakes, himalayan region, late night, sikkim