Science Buddies: "Ask an Expert"

I just finished experimenting and analyzing my project. My project is related to earthquakes or specifically, epicenters. My problem was "Do all seismograms have their own epicenter?" and I found out that they don't. Instead, an epicenter has two or more seismograms. If it sounds confusing, I'll explain it. What I meant in my problem is that do all epicenters have their own seismogram. Then I found out that they don't because two or more seismograms share the same epicenter. Clear enough? So after that, my teacher told me to come out with a recommendation about what would I do if I can do it differently again. And I wrote this-

My recommendation to those who perform this type of experiment is that they should try to make their own seismograph and record the seismic waves generated by earthquakes in a specific area. This may increase the accuracy of their data and it also may make their project much more interesting. But it will take a very long period of time to do so.

My teacher said that making your own seismograph will do no good because you are not an expert at this and instead of increasing the accuracy of the data, you will probably decrease it.

That means I really need help with coming out with a recommendation.

My other problem is to come out with an application. The teacher said that an application is like what was point of doing your project/how is it useful for other people. And I wrote-

This experiment was to let other people know that when an earthquake occurs, they should evacuate as soon as possible because the epicenter that causes the earthquake may be unstable and may cause another earthquake again and the reason is that the epicenter may be far away from you but it may affect you as well but it depends how strong its magnitude is.

My teacher said that it will be too late to evacuate during an earthquake because buildings are already collapsing and you never know where and how strong the epicenter is.

So basically, I need to come out with a recommendation and an application. Please help? Thanks in advance!

EDIT= For the application, don't earthquakes start slow? Does that mean that people DO have the time to evacuate?

brian111,

Welcome to the Ask an Expert forums!

It sounds like what your teacher means by "recommendation" is that s/he would like you to look at your project: your procedure, your data collection methods, your data analysis, etc. and come up with things that you could do differently that would make your project better. S/he is quite correct in saying that building your own seismometer will likely decrease both the accuracy and precision of your measurements.

To come up with your "recommendation", I would suggest looking at your project and answering the following questions: What went wrong? What problems did I run int? Did my method work the way I wanted it to? Was my data analysis method valid and helpful? As you start to think about these questions, you will come to see areas of your project that can be changed and/or improved. These changes/improvements are what you want to talk about in your "recommendations" section. Think about these questions, start brainstorming ideas of things that could be changed/improved and how you would do so, and post back with a revised "recomendations" section.

Regarding your "applications" section, your teacher is again quite right in saying that evacuation of masses of people is not feasible during an earthquake. Earthquake waves travel roughly at the speed of sound. The P-waves are the first waves to be detected by a seismometer, the S-waves second, and finally the surface waves. There is some lag time between the arrival of the P- and S-waves, but this difference in arrival time is not sufficient to allow a mass evacuation. Furthermore, the closer a region is to the epicenter, the shorted the P-S wave interval is.

Based on what you have said in your post, I'm assuming that your discovered that every seismogram does not show a distinct and unique epicenter, but rather that the same earthquake (and therefore epicenter) is recorded by many seismographs. In fact, it takes the data from three seismographs to located the epicenter of an earthquake. The Sumatran earthquake, for instance, was recorded as seismic stations across the globe.

The application of your project, then, is nothing particularly new to the scientific community, but it sounds like it is new information to you: you have shown (if I'm understanding your post correctly) that the same earthquake is detected by many different seismic stations. The application of this is that you can then use the combined information from multiple seismic stations to help determine the characteristics of a particular earthquake or other seismic event.

If there is something you don't understand, please let us know. If you any more questions, again, please let us know.

Good luck with the project; I'm looking forward to seeing your revised "recommendations" section!

You said- "your project and answering the following questions: What went wrong? What problems did I run int? Did my method work the way I wanted it to? Was my data analysis method valid and helpful?"

When I was doing my experiment/rpoject, everything went fine and my data analysis method was valid. My revised recommendation is-

My recommendation to those who perform this type of experiment is that they should try to come out with seismograms that are recently recorded like the earthquake that occured in northwest of Chengdu, China, that killed over 19,500 people. Its magnitude was 7.9 and try to find out if this earthquake has affected other countries because of the 7.9 magnitude.

This recommendation took me 2 hours to come out with, I hope it will really worked! Thanks!

brian111,

Perhaps we would be able to be more help if your explained to us your procedure in detail. Would you take the time to do that, please? It will greatly help us help you.

Your point about using recent seismograms is valid to some extent because seismometers are becoming, to put it in everyday terms, "better". I also think that it would make sense to gather several seismograms recording the same event for your project? Is this what you did, or is this a change you are suggesting someone do if they repeat the project?

I'm not clear how the magnitude of an earthquake directly relates to your project. I thought you were trying to see if each seismogram recorded a unique event? In addition, knowing the magnitude of an earthquake won't necessarily tell you whether that earthquake affected multiple countries. Perhaps you can provide more information about how things things specifically relate to your project in addition to your detailed procedure.

Looking forward to your next posts!