TC1 user guide - What is Seismology?
Contents
1. SEHE E cali HE TC1 user guide EE between the clear tube and the black base Spring can stretch or turn over time so corrections may be needed Depending on the TC1 version that you have the NERdaq and Arduino Uno board are either integrated inside the TC1 A or in an independent grey box B Plug the sensor s NERdag amplifier USB cable from NERdaq amplifier into a computer Finding the correct place for your TC1 The most important factor is aGOOD ground coupling A table is not a good idea You may also want your students to see it but not knock it over Using a hand held GPS or SatNav system or Google Earth press CTRL L Latitude and Longitude are displayed at the bottom of the screen find the precise latitude and longitude of your station You will need it for AmaSeis and Winquake It needs to be expressed in decimal places so to convert your position data from degree minutes seconds into decimal use for example the following program http www directionsmag com site latlong converter AM TC1 user guide EE South and West are written as negative values whilst North and East are positive Step 2 Downloading softwares To acquire and process data you will need to upload three softwares Arduino AmaSeis and Winquake Depending on operating system the programs to download will be located in slightly different web places At this stage the seismometer is plugged in the computer A2. TC1 user guide AM TC1 user guide Foreword There are around 500 000 earthquakes each year 100 000 of these can actually be felt The largest earthquake ever recorded was a magnitude 9 5 Mw in Chile on May 22 1960 The world s deadliest recorded earthquake occurred in 1556 in central China It struck a region where most people lived in caves carved from soft rock These dwellings collapsed during the earthquake killing an estimated 830 000 people The normal average is 33 earthquakes of magnitude 5 and above per 7 days Scientists use seismometers sometimes also called seismographs to record the Earth s vibrations generated by tectonic earthquakes volcanic eruptions and other seismic sources such as nuclear tests From these recordings earth structure can be inferred and tectonic plate boundaries mapped The holy grail of seismologists finding a method to predict earthquakes and eventually saving lives is still way out of reach of any legitimate and competent scientist Owning a TC1 a vertical component seismometer is an exciting way to be involved in such a scientific adventure This manual intends to assist you setting up your new instruments and answer as many questions regarding the setup as possible For the last 5 years in Fulneck School Leeds UK I have enjoyed using a seismometer as a teaching and learning tool Teaching with a seismometer generated lots of interest in my students opening up my classro
3. 74 5 605 617 Sept Oct 2003 5 Thomas J Owens R E Mereu Alan L Jones H Philip Crot well and Mitch Withers Of drums and needles disappearing icons of seismology Seismol Res Lett 74 1 44 47 Jan 6 http www arachnoid com abouttime index html 7 S amp H Jeffreys and K E Bullen Seismological Tables Office of the British Association 1958 8 See for example G Nolet Seismic wave propagation and seis mic tomography in Seismic Tomography 1987 p 1 23 University of Auckland New Zealand kyanwik auckland ao nz 554 THE PHYSICS TEACHER Vol 51 DECEMBER 2013 RE
4. DECEMBER 2013 AM 32 raw analog signal and computer j mi m oo mu ih oo td dd Fig 2 Snapshot of tha seismic data recorded on station TCID in Eagle ID on Oct Cm Fig 4 Part of the seismic data from Fig 3 that contains the signal from an earthquake located off the west coast of Canada The different seismic waves arriving in Idaho have been annotated stream is then subject in software to three digital filters 1 alow pass minimum phase filter at about 2 Hz to reduce noise 2 aband boost filter that enhances the signal between 10 and 20 s to highlight short period surface waves and 3 a high pass filter with a 30 s cutoff to remove drift TC1 user guide The first filter introduces an impulse delay of about 0 4 s which we judged tolerable The other filters have little effect on the high frequency P wave arrival The system is implemented on a printed circuit daugh terboard that couples directly to the Arduino Uno although the analog part is simple enough to wire by hand The latest version of the TC1 has the NERdaq built into the bottom part of the sensor case with its output fed via USB to the host Amaseis Once signals are filtered and converted from analog to digital in the NERdaq we display the seismogram on a PC with software named Amaseis written by Alan Jones for the IRIS Seismometers in Schools program While originally written for the AS 1 vertica
5. Extract the Earthquake using Amaseis First you use the AmaSeis program If the earthquake is recorded on the current datalogger screen highlight the earthquake trace using the event time on the USGS notification sheet as a guide fig 2 N Morse TC1 user guide 17 if wo p OF verre EI S nt ERTEILT BEA SOS o 1t Me Hm Z s LOC TIME Tul I X T UTILI un 4 LR a aa ele ie ee ee ee Se a An a u un eli g IUNII wer 4 778 s w Ba o w v Fui Wa 4 NR oe a Tua oum RAMS te ee a udi ual de c Fw AT VW tay M Mum a AP ma onte tuos f ww Len n wm m DELETE WIEN ERINNERTE EI to fA De I Ft AI A FAO ILU N ee aU E o s dM oU tss da a oe d u am te LL u in OU tg te ee m LL B SG u c m demo ut spree me Ar a are mee modb me A ep a eet meted un amis AT M ee LS a Las R am Ao e vl sd o a Ao pao uirgo oe dp Mp 1 drm MM men n L a La wv tem cal Aum mus tarta naa cv crm oem d am een en rn scm I m ele hanes 3 i bie lit zr SU Re SLE x mme in innen fm gen armpit eben ind Highlighted earthquake trace on datalogger screen Where to start and end highlighting the trace is optional however you may find the following suggestions helpful e Others may be comparing your data file with theirs so some continuity in time lines is beneficial If the event time is 11 43 for e
6. seconds m Time Reference 80 Type Sms Dl NR None Y Not Locked Y 14 30 48 32 18 33 48 35 18 36 48 38 18 39 48 41 18 42 48 44 18 45 48 47 18 48 48 50 18 51 48 53 18 54 48 56 18 57 48 59 18 Applying a time correction in the UTC Time window N Morse TC1 user guide 31 That should move the P and S phase markers to their correct positions Then pull down the File menu and Save as SAC binary fig 13 Now when the SAC file is closed and reopened the changes should be saved and the P and S markers located correctly F WinQuake 110407 143241 BSU3 sac File Calculate Display Modify Tables View X Scale Y Scale Options Window Help jse Ble Bfs Hl m r r Sal mjeh e s Mill 110407 143241 BSU3 sac Start 4 07 11 14 30 36 UTC Station BSU3 43 66N 116 24W Samples 35150 SPS 20 001667 he Rm Dat e Invert Data on None IV DC Offset m Save Data Type 7 Auto Integer 16 bits L eu Float 4 byt a Ee Archive Name Mak IV Long File Name Make Dies V Use Event Time GIF Settings VW Overmite Message Save Format Emm o Can cel Help 14 30 37 0 X 1756 Sec Y 400c P 2 File saved as SAC Binary This software situation should be corrected in the newer versions of WinQuake Ad TC1 user guide Appendix B Teaching Geophysics with a Vertical C
7. 30 Nov 2010 03 24 41 UTC 30 Nov 2010 13 24 41 near epicenter 29 Nov 2010 20 24 41 standard time in your timezone Location 28 415N 139 138E Depth 478 km Distances 337 km 210 miles WNW 297 degrees of Chichi shima Bonin Islands Japan 458 km 285 miles NNW 332 degrees of Iwo jima Volcano Islands Japan 712 km 442 miles S 169 degrees of Hamamatsu Honshu Japan 808 km 502 miles S 184 degrees of TOKYO Japan Location Uncertainty Horizontal 13 2 km Vertical 0 5 km Parameters Nph 514 Dmin 334 0 km Rmss 0 65 seconds Gp 25 M type M Version B Event ID US c0000h7t For updates maps and technical information see Event Page or USGS Earthquake Hazards Program National Earthquake Information Center U S Geological Survey http neic usgs gov Disclaimer This email was sent to tchannel cableone net You requested mail for events between 90 0 90 0 latitude and 180 0 180 0 longitude for M5 5 at all times Your account has aftershock exclusion turned on This event fell into the UScO000h7t exclusion region but was large enough to trigger Example of USGS Notification 2 Process the Earthquake Processing will involve two software programs AmaSeis and WinQuake AmasSeis is the viewer and logger where the earthquake traces are recorded in 24 hour time hereafter called the datalogger or datalogger screen and WinQuake is used to edit filter print and publish the earthquake data i
8. recorded P waves you have identified the trace correctly Pull down the Display Modify menu again and left click on Event Information again Highlight the xxx in the Comment box and enter the correct number of kilometers which has automatically been entered in the descriptive information at the top of the earthquake image More on the phase markers If desired click on View Phases Display You can select the different phases you want displayed on the earthquake image If you want to print the earthquake image with these phases marked Save and overwrite the old file File Calculate Display Modity Tables View X Scale Y Scale Options Window Help Sela Blej mrs jp x F Gal ma e rl Station Eagle Id 43 6137N 116 416W Samples 25240 SPS 20 0 dian Id MHSID BONIN REGION Max Min 19 78 28 96 X 21 01 0 Y 8 9mv ong 20 415N 139 138 Depth 478km 297 Omi Mag Mw6 6 23 1 Diff 9 26 1min Dist 80 459deg 8945 2km 5558 3mi Mag MI JB 478 Cursor 3 31 18 0 Y 26 1 7966 mv 329100 X 1261 Sec Y 8 9mv gt 2 WinQuake automatically adds phase markers when the Event Information is completed When you are satisfied with the final earthquake image pull down the File menu and Print a copy if you wish You can also use the Google Earth feature to fly from the event to your station Mitra TC1 user guide 24 After printing is done the completed earthquake image can be saved in two formats for posting 1 PSN Type
9. 04 07 14 32 41 0 Lat Long 38 253N 141 64E Depth 49km 30 4mi Mag rn Org 14 32 41 0 P 14 44 03 1 14 53 21 3 Diff 9 18 2min Dist 72 295deg 8037 6km 4994 3mi Mag MI JB 49 AUC M71 8037 km from BSU3 JAPAN ime pr 04 07 2011 14 32 41 0 er mm dd yyyy hh mm ss s pi Latitude Longitude Depth Agency Event Type Quality f38 253N 141 64E a9 SET 381510N 14 3824E km Evert 1 New _Deiete _r Event Report Information 14 30 448 0 X 1756 Sec Y 400c IP Event File Information window e Pulldown the Display Modify menu click on Time Information In the Event File Start Time window adjust the time according to the correction you noted when you corrected the computer clock If for example the computer clock was 9 seconds fast enter 00 00 09 in the UTC Time window This subtracts no hour no minutes and 9 seconds from the earthquake trace If you wanted to save as a PSN file you could enter 9 in the Start Time Offset window but for an SAC file enter the correction in the UTC Time window Click OK If you need to add increments of time do not enter a minus sign I VE TC1 user guide 30 Tue WITKJUSKE LLUSU 145241 55U5 5aC File Calculate Display Modify Tables View X Scale Y Scale Options Window Help oe E Event Information LiF itii i a Bsr Sensor Information juli 110407 1432 Time
10. 1 16 33 0 Lah oaa 19 8425 70 EESW Doak 35km 21 7mi Mag M Org 21 16 34 9 P 21 28 18 564 S 21 37 56 46 Diff 9 37 825min Dist 75 718deg 8418 pl 5230 8mi Mag MI JB 35 Places 4 yw ces ing T Temporary Places hnQual TI AMA UU AM ul RIP AL LU M TON PE PHI Y Ed udis dad i v Laye Earth Gallery gt gt a s Prima he bas Borders and La ls B Places Y Photos EZ Road a a 3D Buildings W 9 Ocean i Weather B Gallery wv Global Awareness More Cursor 03 16 21 17 153 Y 743 21 14 52 0 X 3601 Sec Y 300c Google earth Page 11 of 33 Words 3 786 um 7 Rs M You are now nearly ready to record seismic activity and process data Step 3 Acquiring data and processing earthquakes 1If you experience registration issues log into the computer as Administrator and turn off UAC This page http windows microsoft com en us windows vista turn user account control on or off has information on how to disable it Once you do that you should be able to register WinQuake Once you have it registered you can turn UAC back on again AM TC1 user guide This is a very important step you need to have correct computer time to be able to process earthquakes The computer clock must be accurate within a few seconds and an A Adjusting the time unaided computer cannot hold this tolerance If your computer does not have an automatic time setting and adjustment device which
11. 4 or SAC Binary and 2 GIF Pull down the File menu and click Save Under Save Format click on PSN Type 4 or SAC Binary bottom of File Save window Click OK fig 9 Wil WinQuake 101130 032441 mhsid psn Fee File Calculate Display Modify Tables View X Scale Y Scale Options Window Help Ale mrs vs e z F Sal mmj rl ll 101130022441 mhsid psn Start 11 30 10 3 29 09 UTC Station Eagle Id 43 6137N 116 416W Samples 25240 SPS 20 0 Comment M6 6 10570km from Meridian Id MHSID BONIN ISLANDS JAPAN REGION Max Min 19 78 28 96 X 21 01 0 Y 8 9mv Event Time 11 30 03 24 41 0 Lat Long 28 415N 139 138E Depth 478km 297 0mi Mag ej js Mw6 6 Org 3 24 41 0 P 3 36 03 0 S 3 45 29 1 Diff 9 26 1min Dist 80 459deg 8945 2km 5558 3mi Mag MI JB 478 File Ni events1201 O nov2010 101130 032441 mhsid psn EI Long Name r Save Options z Save Nth Data Point n F Dataset Volume Invert Data Y Compression None Iv DC Offset 7 Save Data Type V Auto Integer 16 bits pera ee es Float 4 bytes Double 8 byte Archive Name li E 5 IV Long File Name Jl Make Directory Rip Gat VW Use Event Time GIF Settings IV Overwrite Message Save Format PSN Type 4 v Cancel Help Ber ie 4 PSN Type 3 PSN Text SAC Binary GIF Image 3 29 10 X 1261 Ser V 8 9mv Ip Save the completed earthquake image as PSN or
12. 7 Station Eagle Id 43 713N 116 41W Samples 25240 SPS 20 0 Max Min 19 78 28 96 X 21 01 0 Y 8 5mv Org 3 28 25 6 P 3 29 49 4 S 3 30 54 0 Ditt 1 04 amp min Dist 5 652deg 528 4km 390 4mi Mag MI JB 33 Earthquake trace after filtering If you adjusted the time on the computer you need to adjust the time on this earthquake display also because the traces were recorded when the computer clock was running at an inaccurate time and if not adjusted will cause WinQuake to misplace the earthquake phase markers If you adjusted the time on the computer see instructions in Appendix A Now enter both your Sensor information and the Event information Pull down the Display Modify menu fig 7 click on Sensor Information and enter the latitude longitude and elevation of the station then click on Event Information and enter your data You can find earthquake information on either USGS website http earthquake usgs gov earthquakes IRIS Website http www iris edu seismon Geonet website for more local earthquakes http www geonet org nz AM TC1 user guide 22 WM WinQuake 101130 032914 ch2 psn 0 File Calculate Tables View X Scale Y Scale Options Window Help e ormation F CH a e er e ormation e Id 43 713N 116 41W Samples 25240 SPS 20 0 04 6min Dist 5 652deg 628 4km 390 4mi Mag MI JB 33 GoogleEarth i I Mr TH Hut t 14 E IL PM TT juae de A gab ul ul BON D OW C AFTE
13. AKE A NOTE OF THE NUMBER XX WRITTEN AFTER THE COM e Next choose the Browse my computer for Driver software option e Finally navigate to and select the driver file named arduino inf located in the Drivers folder of the Arduino Software download not the FTDI USB Drivers sub directory e Windows will finish up the driver installation from there M Aere Nehmen TC1 user guide B AmaSeis AmasSeis is the datalogger It is the software that displays the ongoing activity recorded by the TC1 With Amaseis you will be able to visualise the seismic activity as well as select extract and save earthquakes files Access it at http pods binghamton edu ajones AmaSeis html Click on Fetch Version 3 2 Level 2012 07 06 here AmaSeisSetup exe Follow the prompts from the Windows installation wizard C Winquake Winquake is the software that will allow you to analyse and process the earthquakes It contains lots of necessary features such as filtering processes event distance and magnitude calculations calculation of P and S wave arrival times and a link to Google Earth You need to decide whether your computer is running a 32 Bit or 64 Bit operating system To do so check in Control Panel System and Security System Then access 32 Bit http www seismicnet com software wq336b 32bit exe 64 Bit http www seismicnet com software wq336b 64bit exe Run the installation and then follow the prompts from the Windows in
14. Arduino As the digitalisation of the analogue signal is done via an Arduino Uno microcontroller board you need this software such that your computer can read the signal The program size is about 250 Mb Access the page http arduino cc en Guide Windows 1 For Windows Vista 7 XP Access the page http arduino cc en Guide Windows Scroll to point 2 2 Download the Arduino environment Get the latest version from the download page Click on download page Scroll to Arduino 1 0 5 Click on Windows Installer and select Run Agree to the terms and conditions then click next then Install You then need to install the Arduino driver Follow the subsequent instructions not as daunting as it looks promise e Plugin your board and wait for Windows to begin its driver installation process After a few moments the process will fail despite its best efforts e Click on the Start Menu and open up the Control Panel e While in the Control Panel navigate to System and Security Next click on System Once the System window is up open the Device Manager e Lookunder Ports COM amp LPT You should see an open port named Arduino UNO COMxx e Right click on the Arduino UNO COMxx port and choose the Update Driver Software option PLEASE MAKE A NOTE OF THE NUMBER XX WRITTEN AFTER THE COM N N We wi reati amie pleni Poner TC1 user guide e Next choose the Browse my computer for Driver software option e Finally nav
15. Information ce Je Ja Start 4 0771 3 66N 116 24W Samples 35150 SPS 20 001667 Comment 8 Next Event tKe 9 9 392 1 X 29 16 0 Y 400c Event Time 53N 141 64E Depth 49km 30 4mi Mag Org 14 32 4 Data Operations ff 9 18 2min Dist 72 295deg 8037 6km 4994 3mi Mag MI JB 49 GoogleEarth gt ig ecc i eet Du ic ue moe ccce l vocor eC ee I ee dime EIE Dan ARR RR E eee eee ee ees ER Ree eee eee ee etuer eee ee RE ee ee eee ee 14 30 48 32 18 33 48 35 18 36 48 38 18 39 48 41 18 42 48 44 18 45 48 47 18 48 48 50 18 51 48 53 18 54 48 55 18 57 48 i Time Information menu Pull down the File menu and Save If you do not do this step when you close the Event Information will be removed bM WinQuake 110407 143241 BSU3 sac File Calculate Display Modify Tables V Help iew X Scale Y Scale Options Window el B e grs te Ma RZ frr lun IIF 3 THI iil ML Rer F 110407 143241 BSU3 sac Start 4 07 11 14 30 47 UTC Station BSU3 43 66N 116 24W Samples 35150 SPS 20 001667 Comment 8037km from BSU3 Max Min 399 9 392 1 X 29 16 0 Y 400c amyn Event Time 04 07 14 32 41 0 Lat Long 38 253N 141 64E Depth 49km 30 4mi Mag Org 14 32 41 0 P 14 44 03 1 S 14 53 21 3 Diff 9 18 2min Dist 72 295deg 8037 6km 4994 3mi Mag MI JB 49 Evert Sensor Time a as u ers Event File Start Time 320 UTC Date UTC Time Miisecond Il 240 Stat Time Offset l 0
16. N UM d BRL j I 1 1 i IR N Fl l lu Lil TT R Iu Lu t dh kurta lil IH TRI a ad d UM LE LT I EOE a E 1 RIE TINE N IINE ian N nm j I ap Display Modify menu You need to enter your Sensor information only once WinQuake will save your Sensor information For the Event information in the Comment box enter the information as given on the USGS notification sheet Use the format M7 5 xxx km from BSU1 Taupo ID NAME OF EARTHQUAKE e Enter the time of the earthquake for example 11 30 2010 05 56 59 e Enter the magnitude in the Mw box e Enter the latitude and longitude of the earthquake Ensure that the latitude ends with the letter N north or S south and that the longitude ends with the letter E east or W west Another way of entering these coordinates is o entera plus in front of the latitude number indicating North latitude or a minus indicating South latitude o entera in front of the longitude number indicating East longitude or a indicating West longitude Taupo is 38 7 or 38 75 latitude and 4176 0 or 176 0E longitude e Enter the depth of the earthquake At the bottom of the window click OK The P and S and any other phase markers you may have specified should now be show fig 8 Other information such as arrival times distances etc also has been automatically entered Meus TC1 user guide 23 If the predicted arrival time of the P waves fit your
17. SAC and GIF Pull down the File menu again and click Save Under Save Format click on GIF Image Click OK Close WinQuake x If you save your file as an SAC binary additional steps may be required See Appendix A Step 4 Networking with other schools using IRIS some real seismology WinQuake is an ideal program to help you identify which earthquake you have recorded However seismologists cannot extract much information using a single station AM TC1 user guide With your station knowing the time interval between the P wave arrival and S wave arrival you can evaluate the epicenter distance at which these waves were emitted using the graph below from http edition cnn com fyi interactive 0006 riverdeep earthquakes earthquake tips a html Earthquake P wave and S wave Travel Time TRAVEL TIME minutes EPICENTER DISTANCE x10 km WinQuake allows you to measure such a time difference and from the equivalent epicenter distance you could plot manually on a map a circle corresponding to the distance or use WinQuake directly using the tab View Locate Event AM TC1 user guide 26 fie Calculate Copy Zoom Options Window Help su 5 Be Cursor Lat 14 9 l Long 153 5 Dist 4106km Az 54 8 Stations AUCK ZHI Event Lat 40 65 Long 175 864 Depth 27km Mag Mw6 3 Date 01 20 14 Time 02 52 44 2 54 48 0 X 37135ec Y 110um s P 4 Using the data from 2 stations you ca
18. ake trace and enhances the desired frequencies The undesired frequency called noise can be generated by traffic students in the AM TC1 user guide classroom even wind applying forces on the building that contains the seismometer Click on the F icon on the top toolbar for filtering fig 5 Depending on the type of earthquake you presume to have recorded select the following Teleseimic event gt 1000km 0 5 1 2 from station H WinQuake 101130 032914 ch2 psn File Calculate Display Modify Tables View X Scale Y Scale Options Window Help sjela Be Els mel renal F ml e r l 101130 032914 ch2 psn RE Time Domain Filtering ss Start 11 30 10 3 29 14 UTC Staten Eagle Butterworth Filter Type AD SPS 20 0 en 79 3 241 7 X 21 01 0 Y 75mv uiia e l rg 3 28 25 6 P 3 29 49 4 S 3 30 54 0 Diff 1 0 mi Mag MI JB 33 LowPass fi 2 High Pass o 05 2 Save as default m Predefined Filters 4 Add Remove Undo Filter Close Cursor 3 41 41 7 Y 180 6 55 102 mv 3 29 15 0 X 1261 Sec Y 75mv P Z Applying a filter to the earthquake trace The data file should now look better as seen below An TC1 user guide PAL File Calculate Display Modify Tables View X Scale Y Scale Options Window Help Selm Ble rs mass s es x Ra miris e Start 11 30 10 3 29 14 UTC
19. be Position magnet assembly inside white coil and copper damper N nien TC1 user guide Top of magnet assembly should be even with top of white coil body Heights are set before shipping but if correction is needed turn magnets and nuts up or down From a side view raise or lower the slinky spring using the knob on the top cap to make the coil magnets even with the top of the white coil From a top view center the coil magnets like a bull eye into the white coil body leaving an even air space all around with nothing touching the white coil Do this using the three black base leg knobs or base screw N Marce TC1 user guide Repeat the same centering process with the copper damper tube and magnet Damper magnet height should be about even with the top of copper damper tube Again the heights are set before shipping but if correction is needed turn magnets and nuts up or down Use three adjusting legs on base to center magnets like a bulls eye inside coil and damper with equal free space all around Magnets must not touch inner walls or the sensor will appear to be working but will never record an earthquake Periodically ensure everything is still centered NOTE On the side of the black base is a small brass screw used for shipping Back this screw off and rotate the clear tube about 1 Finger tighten only this screw against the clear tube to make for a tighter fit
20. ddate com worldclock c ity html nz22 if you are uncertain aH BM 4140 9 8 7 6 5 4 3 2 1 0 ol 2 3 of oB 6 7 8 9 10 11 t2 UTC 0 UTC That s it you are now recording seismic activity AM TC1 user guide 15 C Which earthquake have you recorded Let s process the data Now the real fun begins Seeing a trace on the computer screen on AmaSeis you will want to identify which earthquake you have recorded the who s done it aspect of the project This is when you will use WinQuake Seismograph However you need to know where Station earthquakes happen the suspects on the ww who s done it list In New Zealand the Earthquake task is made more exciting by the fact that there are teleseismic events distance station epicenter 1000km as well as many local events picture http www iris edu Teleselsmic Earthquake For the local events Geonet is the best source of information For teleseismic events IRIS seismic monitor http www iris edu seismon is a good source as well as USGS You can get seismic alerts sent to your email mobile as explained below 1 Receive USGS earthquake notifications To receive USGS earthquake notifications access the USGS Earthquake Hazards Program Website http earthquake usgs gov Select tab Real time feed and notifications Select Earthquake Notification service Subscribe You will receive text or email messages notifyi
21. define the epicenter zi Pewee travel time Sowawe travel time Time CCS en nave Fig 5 M UR er aul See arrival times in blue and green respectively This is overlaid onto a P and 5 wave travel time plot for epicenters from 0 to 60 At 43 the S P wave travel time matches the curves Fig amp World map with the members of the Z MET indicated by stars The 104 and 145 contours outline the P wave shadow zone for station TCID blue star Because of the drop in P wave speed in the liquid outer core TCID does not record direct P waves from this region Service Learning and the Z NET Student engagement through hands on learning is a pro ductive learning strategy that integrates well with service learning the promotion of student learning through relevant community service In this case students learn seismology by building a seismometer helping a K 12 teacher set it up in his or her classroom and then teaching K 12 students about the subject matter As a result undergraduate students have been mentors for institutions of secondary education Now TC1 user guide some 50 TC1s populate the planet in our network called the Z NET pronounced zed net Fig 6 If the TC1 user marks each epicenter of the earthquakes it records on this map it will not be long until tectonic plate boundaries are outlined Conclusions The robust TC1 seismometer easy to build and under stand acts as a gateway to
22. e Time 21 16 33 en TC1 user guide If not all the lines fit on the square it most likely means that the computer time of one of the recording stations is inaccurate and needs correction To get a different perspective you can get the globe to rotate by double clicking on the green dot located next to big cities Don t forget to try the Google Earth option in Winquake and fly your students and yourself from your station to the event Explore and Enjoy Step 5 Problems Help is at hand For questions please contact Ted Channel tchannel cableone net Dr Kasper Van Wijk k vanwijk auckland ac nz Dr Caroline Neuberg caroline choux gmail com More information can be found at http cgiss boisestate edu ssis or http tclseismometer wordpress com N M APER wi ee ak amie plns Poner TC1 user guide 29 Appendix A Saving SAC Binary File Time Correction If you save your file as an SAC binary additional steps may be required Make sure the Sensor and Event information have been entered and click OK Ail WinQuake 110407 143241 BSU3 sac ter File Calculate Display Modify Tables View xX Scale Y Scale Options Window Help i jse Ble Es to Ma 84 m 1 F Gal Del e e All 110407 143241 BSU3 sac Start 4 07 11 14 30 47 UTC Station BSU3 43 66N 116 24W Samples 35150 SPS 20 001667 Comment 8037km from BSU3 Max Min 399 9 392 1 X 29 16 0 Y 400c Event Sensor Time Event Time
23. e P followed by the slower secondary or S wave and seismic waves that bounce off the surface and main interfaces of the Earth core mantle crust Seismic waves that travel along the Earths surface so called Rayleigh LR and Love waves LQ make their way from Canada to the TC1 station in Idaho as slower but more energetic signals The predicted seismic phases overall match the data which means that the approxi mation of a spherically symmetric Earth structure is not bad at all In fact it is the small deviations from this approxima tion that seismologists use in seismic tomography to unravel the details of the Earth s subsurface structure THE PHYSICS TEACHER Vol 51 DECEMBER 2013 553 Finding the epicenter with the TC1 network To estimate the epicenter of an earthquake schools can first compare the arrival of the P wave at various stations The earlier the arriving P wave the closer a station is to the epicenter While this can provide a first order estimate with a large network students can then try to identify arrival of the secondary wave S wave The time difference the S and P wave S P from an earthquake recorded at a specific station determines the distance from that station to the epicenter Fig 5 Students can then draw a circle with a radius that equals this S P distance on a map The earthquake could lie anywhere on this circle but similar epicentral dis tance circles from two more TC1 schools uniquely
24. e icon The enlarged image will now appear in a different window as an enlarged image fig 4 TC1 user guide File Settings Controli Help fa Makan coe Pd dtu el 2m N esses 2002 11 43 229 S d il to 1600 roo A a I EO A x 1 ald il n 4 D I T in A h f l 500 Mill 000 2150 snug Enlarged image of extracted earthquake trace At the top left of the toolbar pull down the File menu click Save As Save on Desktop Name the file as follows beginning with the year month and day yymmdd then the time hours minutes and seconds then the station name Use a period between each set of identifiers and use no spaces 110328 103521 BSU date time station name Save the file as a PSN or SAC file to the desktop Click on Back at the top left of the enlarged earthquake screen see in figure 4 this restores the AmaSeis datalogger screen On the toolbar in the datalogger window click Now to return the datalogger to the current day Minimize AmaSeis the datalogger window Don t close x ii Identify the earthquake using WinQuake Now you can see the file you just saved on the desktop Double click on this file to open it in WinQuake To process your data you will need to filter it Filtering is important because it removes undesired frequencies from the earthqu
25. following describes in broad strokes the components of the TC1 Detailed instructions including the Bill of Materi als on how to build a TC1 seismometer are available online at http tclseismometer wordpress com Fig 1 Left Photograph of the TC1 sersmometer based on a mag net and Slinky toy spring Right a close up of the bottom of the induction coil the damping system of a magnet inside a copper Spring mass coil and magnet At the heart of the TC1 seismometer is a harmonic oscil lator composed of a mass on a spring inside a clear plastic frame with legs Fig 1 Ground motion moves the frame but the inert mass resists movement Our spring is a Slinky toy with a natural period around 1 s and the mass a neodymium magnet The magnet is positioned inside a handmade coil consisting of many wraps of narrow gauge copper wire and which is attached to the frame When the frame is disturbed by ground motion the magnet on the spring moves relative to the coil which leads to an induced current in the coil Magnetic damping To isolate seismic vibrations from the ringing of an ex cited harmonic oscillator we damp the system Historically seismometers were damped using friction from a viscous fluid such as oil but here we use magnetic damping with a second magnet suspended well below the first magnet on the spring This second magnet is positioned inside an isolated copper tube attached to the frame When the sensor is pe
26. igate to and select the driver file named arduino inf located in the Drivers folder of the Arduino Software download not the FTDI USB Drivers sub directory e Windows will finish up the driver installation from there 2 For Windows 8 and 8 1 Arduino drivers have been updated to add support for Windows 8 1 The version to download is version 1 0 5 r2 located under the title Arduino 1 5 6 r2 BETA with support for Arduino Y n and Arduino Due boards Access the page http arduino cc en Guide Windows Scroll to point 2 2 Download the Arduino environment Get the latest version from the download page Click on download page Scroll to Arduino 1 5 6 r2 BETA Click on Windows Installer and select Run Agree to the terms and conditions then click next then Install You then need to install the Arduino driver Follow the subsequent instructions not as daunting as it looks promise e Plugin your board and wait for Windows to begin its driver installation process After a few moments the process will fail despite its best efforts e Open up the Control Panel by selecting Settings in the Charm list e Select the section Device and printers and the option Device manager accept the changes on the pop up window e Look under Ports COM amp LPT You should see an open port named Arduino UNO COMxx e Right click on the Arduino UNO COMxx port and choose the Update Driver Software option PLEASE M
27. it would have if your school has a network use a device like an atomic clock or an Internet program an excellent resynchronize time http www pretentiousname com timesync You can adjust your computer time by clicking on the time on the right bottom corner of the screen select change date and time settings select the tab Internet time and let your computer adjust to the internet time Alternatively you can download an atomic clock program from http download cnet com Atomic Clock Sync 3000 18512 4 14844 html Beware not to download the attached program called Jotsey Select the Decline option Before processing note any clock error and write it down to be used later in WinQuake Appendix A B Setting up AmaSeis Open AmasSeis You may get an error Can t open COM port and then another error This is because we need to set up AmaSeis NOTICE IF YOU GET THIS ERROR AFTER YOU WERE SUCCESSFUL IN SETTING THINGS UP IT MAYBE BECAUSE YOU HAVE ANOTHER AMASEIS RUNNING AND MINIMIZED ON THE TASK BAR YOU CAN ONLY HAVE ONE AMASEIS OPEN Go to AmaSeis settings device and select SEPuk1 Go to AmaSeis settings COM port and change it to the same com port as indicated in the device manager for the Arduino Uno hardware found Please refer to Step2 Section A Close AmaSeis and reopen hopefully you will get no error this time Go to Amaseis settings this station and enter the latitude longitude and elevation of your statio
28. l seismometer and its black box interface the TC1 system seamlessly operates with Amaseis On the same computer timing accuracy is ensured with a free version of software called AboutTime Classroom seismology Once the TC1 is completed exciting seismic records such as in Fig 3 are quite common These are a starting point for inquiries in a number of concepts in seismology supporting lessons about the Earth s subsurface structure and processes We encourage the students to enroll for an automated warn ing system such as the one run by the United States Geologi cal Survey USGS so that students are notified when signifi cant earthquakes have occurred Earthquake identification When students observe an anomalous signal on their sen sar an email or text message from the USGS can confirm or deny if this was a bump of the instrument the recording is from an earthquake Figure 4 shows the data that contain the main energy recorded from an earthquake with magni tude 7 8 off the west coast of Canada from Oct 28 2012 at 03 04 08 UTC Annotated are the predicted main arrivals of different seismic waves based on a spherically symmetric model of the Earth We used Larry Cochranes Winquake software but freeware alternatives with similar capabili ties such as Obspy and Amaseis are available Most obvi ous is the prediction and the onset in the data of the fastest seismic wave the primary or P wave is marked with a singl
29. le epe Pete TC1 vertical component seismometer Designed by Ted Channel Poster by Dr Caroline Neuberg and Sarah Keehan a Spring the spring moves vertically when there is an earthquake It oscillates and moves the mass up Band down B The bigger the earthquake the bigger the movement Mass it is a magnet that moves up and down when there is a movement There is a difference in time between the movement of _ the magnet and the other vu components of the seismometer 4 Coil as the magnet moves relative E to the coil an electric current will EZEERSL j be created in the copper wire that iy BAA ee forms the coil The biggef the movement the higher the electrical current faster Copper tube and magnet to catch the different waves arriving at the seismometer the spring must be prevented from oscillating for too long The copper tube dampens the oscillation slowing it down Digitiser it transforms the electric current generated by the coil into a signal that a computer can understand It transforms the signal from an analogue signal to a digital signal TC1 user guide TC1 vertical component seismometer Designed by Ted Channel Poster Dr Caroline Neuberg Acrylic tube it gives shape and B protects the spring from drafts E Spring Depending on the stiffness of the spring called spring con stant k in N m and the mass hanging o
30. learning the underlying physics of the sensor Topics such as inertia damped harmonic oscillators induction and eddy currents pass in revue in the assembly phase Upon completion the end product of earth quake recordings sparks discussions about the physics of the Earth including plate tectonics structure of the deep Earth and peohazards We thank all the students who helped build and teach with the TCL The IRIS consortium generously hosts snapshots of seismic records of the Z NET while Chris Knudsen from New England Research Inc helped design the NERdaq Larry Cochrane provided us with Winquake Kara Ferguson and the service learning team at Boise State University were instrumental in integrating the TC1 in the classroom KvW acknowledges NSF s support through award EAR 1142154 Last but not least we thank Linda Channel for it was her enthusiasm that started our journey to build seismographs but her ongoing support makes this project a real pleasure References 1l J Walker How to build a si simple sei quake waves at home Sci Am 241 152 161 1979 2 GE Averill Build your own seismograph An earth shaking in class project Sci Teach 62 3 48 52 March 1995 3 EScherbaum Of Poles and Zeros Fundamentals of Digital Seis mology Vol 15 Springer 2007 Sec 6 2 2 4 AlanL Jones Lawrence W Braile and Sheryl J Braile A suite of educational computer programs for seismology Seismol Res Lett
31. n Go to AmaSeis settings helicorder and change the gain to 4 Go to AmaSeis settings show data values in that window you should see a number flickering Aet TC1 user guide 14 Bl Station unk Sett fie Sutings Contrat Vieh 83 AN In B S 2 L Olan 0 Sample rate 6 Decimate factor 1 Gain 20 No filter 1 That s your data coming in Leave this window open so you can monitor the numbers Go to AmaSeis settings set zero level change this number to about 32600 The objective here is to modify this set zero number to whatever brings the Black data line up or down to match and follow the Blue hour line on the helicorder screen You can watch the flickering show data values window until it flickers close to zero This maybe 10 10 or 100 135 could be any numbers Just keep changing the set zero level until the Black data line is following the Blue hour line on the screen M 40 9 8 7 amp 5 4 3 2 0 4 2 3 4 5 6 7 48 9 10 11 12 p OT e NT X hr d y mes p V peer j AR or You will realise that the time displayed on AmaSeis is UTC Coordinated Universal 8 awe zi m am Time time standard used for many Internet and World Wide Web standards as well as aviation For New Zealand the time zone offset is UTC GMT 13 hours or 12 hours depending on daylight savings time Check http www timean
32. n it m in kg it will os cillate when an earthquake hits with a period 7 that is the time taken for one complete cycle of a wave given by r5 k Mass it is a magnet which due to the principle of INERTIA will resit movement felt by the other com ponents of the seismometer cre ating a differential motion Coil using the principle of ELEC TROMAGNETISM as the magnet moves relative to the coil an elec tric current will be induced in the copper wire forming the coil The bigger the relative movement due to a large Seiamic wave the higher the generated current faster Copper tube and magnet to catch the different waves arriving at the seismometer the spring must be prevented from oscillating for too long The copper tube dampens the oscillation using LENZ s law Digitiser Located inside or outside E the seismometer it transforms the electric current generated by the coil into a signal that a computer can understand It is a transfor mation from analogue to digital eee MBA Step 1 Assembly instructions for TC1 TC1 user guide This is what your TC1 will look like once assembled Remove sensor components from cardboard box Remove top ABS cap containing spring Hook eyebolt containing magnets over bottom of spring Insert and lower the magnet assembly into top opening of acrylic tube Ensure ABS cap sits snugly on the tube but do not force it or damage tu
33. n narrow down the position of the epicenter to 2 locations i e the intercept of the 2 circles Using the data from 3 stations will narrow down the choice to one location only the real epicenter of the earthquake This is the reason behind the necessary networking in seismology Iris Incorporated Research Institutions for Seismology provides a free platform for such a necessary exchange of information To network with other schools you need to register your station at http www iris edu hq ssn schools register IRIS Home E amp O Home Ri er S Incorporated Research Institutions for Seismology Sponsored by the National Science Foundation Home Seismic Data Stations Resources Community Register Your Station Contact After registering your station you will be able to upload your recorded seismic data and share it with other stations Privacy Policy Any information you enter will be soley used by the international educational seismology community It will not be distributed to any 3rd parties This information will only used to contact you if there are problems with your application Additionally we may contact you with tips and information about operating your station School Info Bold fields with a are required nn TC1 user guide 27 After registering your station you will be able to upload your own recorded seismic data and share it with other schools For local events it is better to use nearby sta
34. ng you of seismic events Go down to Subscribe Step 2 and Create your account You will be asked a series of questions about the parameters you want to set for receiving earthquake notifications You can use any Settings you want but I use worldwide earthquakes Default World 24 hour notifications and magnitudes 3 0 and greater for the U S and 5 0 and greater for worldwide Skip through the information to Managing Your Email Addresses Select HTML as message format and 00 00 for day begins and day ends Save Skip to Change my account preferences Select Yes for Aftershock Select Yes for Receive updates for events Select No for Defer notifications during night hours After you set up your account you will be notified of earthquakes by automatic email notices fig 1 N Me we ne anale epe Pete TC1 user guide 16 2010 11 30 03 24 41 UPDATED M 6 6 BONIN ISLANDS JAPAN REGION 28 4 139 1 adef Fate File Edit View Tools Message Help From USGS ENS lt ens usqs gov gt Date Monday November 29 2010 8 51 PM To tchannel cableone net lt tchannel cableone net gt Subject 2010 11 30 03 24 41 UPDATED M 6 6 BONIN ISLANDS JAPAN REGION 28 4 139 1 adef Some pictures have been blocked to help prevent the sender from identifying your computer Click here to download pictures 6 6 M BONIN ISLANDS JAPAN REGION X Globe wth Eathauske Location Preliminary Earthquake Report Magnitude 6 6M Date Time
35. om to the world I also like to believe that such an interest helps spark in them motivation for a scientific career Have fun with your TC1 Dr Caroline Neuberg N ree TC1 user guide Contents Step 1 Assembly instructions for TC1 uusssennnnennnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnennnnnnnn 5 Step 2 Downloading softwares eese eene nenne nete nnne nennt toten ennt 9 ARAT UNO ee ee TT 9 LIEF SE EEO WN SV ILS 7 XP ee een ee 9 ZY TOU WU NOS UMC een 10 BBP Sl ici c vse nsec ctr E c Ee 11 eae E TER 11 Step 3 Acquiring data and processing earthquakes sss 13 To TIU uda AERIS NU sw 13 Bi ene UPAMI CONTENT o 14 C Which earthquake have you recorded Let s process the data eese 15 1 Receive USGS earthquake notification ccccccccscssssecesssecesseecessseceseesesceseecseseeceeseecesseecessseceseeeess 16 2 PLOCESS iV E E NES 17 i Extract the earthquake using Amaseis eese 17 ii Identify the earthquake using WinQuake serene 19 Step 4 Networking with other schools using IRIS 24 Step 5 Problems Where to turn for help sees 28 Appendix A Saving SAC binary file time correction sss 29 Appendix B Teaching geophysics with a vertical component seismometer 32 N More wee au
36. omponent Seismometer Kasper van Wijk university of Auckland Auckland New Zealand Ted Channel and Karen Viskupic Boise State University Boise ID Martin L Smith Blindgoat Geophysics Sharon VT arthquakes areS some of the more dramatic expressions of the dynamics of our planet The sudden release of stress built up slowly by tectonic or volcanic processes often has far reaching consequences and can be measured in classrooms around the world This is one reason why de signing and building seismometers has been a popular activ ity and why different versions of Seismometer in Schools projects thrive in the United States Australia and Europe We present a cheap robust and easy to build seismom eter called the TC1 to measure seismic displacements in the vertical direction Its components are easy to obtain and assemble yet the resulting instrument is accurate enough to record earthquakes from around the globe The parts list and building instructions of the TC1 seismometer are freely avail able online Alternatively a complete kit can be purchased for around US 300 Assembling the system naturally introduces students to a number of concepts in physics and engineering while upon completion seismic recordings trigger discussions about the dynamics and internal structure of the Earth The discussions are fostered by service learning and shared in the network of TC1s called the Z NET The TC1 seismometer The
37. r turbed the second magnet induces eddy currents in the cop per tube that counter act the motion of the spring mass The digital acquisition system Like all modern seismometers the TC1 uses a wide dy namic range digital recording system Our system is named the NERdaq We have constructed a simple system consisting of an analog stage with an integral high cut filter followed by a 10 bit analog to digital converter ADC that is heavily oversampled Oversampling is simply the technique of heav ily averaging a noisy stream of digital samples to produce a slower stream with greater effective resolution Figure 2 is a graphical representation of the steps that make up the NERdaq The analog side of the system consists of an op amp that provides a gain of about 800 together with a simple high cut filter that starts to roll off at about 2 kHz This unusually high cut off frequency provides noise to the ADC input that makes oversampling work The digital side is based upon the popular inexpensive open source Arduino hardware in our particular case the Arduino Uno This system supports 10 bit ADC conversion at 9600 samples per second sps We use an averaging win dow of 2048 samples which is stepped by 512 samples to pro vide an output sample rate of 18 78 sps This heavily averaged output has an effective resolution of about 16 bits although system noise uses up one or two bits of resolution The data 552 THE PHYSICS TEACHER Vol 51
38. stallation wizard agreeing to the terms and conditions Select the desktop icon You are then asked to register and asked to have the file PSN associated with Winquake Select yes to the last question Winquake will open with the following screen Go immediately into File on the left corner and select Register software Enter the registration Registration Name New Zealand Schools Registration Code 22499 Eh dnd l Mire we oe anale epu Perte TC1 user guide 12 Close the registration window Using the Google Earth feature of Winquake program you need to download Google Earth on the computer In Winquake under the File menu you should see Google Earth Exe Select it In the Locate Google Earth dialog box locate the GoogleEarth exe file On most systems it is located in this folder directory c Program Files x86 Google Google Earth client After selecting the GoogleEarth exe file you should be to use the Google seat feature 3 Google Earth BI WinQuake 64 1403162114 bajia Eh File Calculate Display Modify Tables View X Scale Y Scale Options Window Help v Seach Q vosso ea s zam EBEE EDETESESUSBRETET TEES to 43 713001 116 410004 Station Search Start 3 1 ae 21 ME 51 UTC es stus 43 713N 118 a en 59905 SPS 16 629662 Get Directions History Ron Comment M7 0 8441km from LCI ar Coast of North ile Max Min 284 ee 5 1 00 01 Y 300c M Event Time 03 16 2
39. tions For large teleseismic events it can be a great exercise to download data from far away stations Upload all the files related to the same event from the different stations downloaded from IRIS onto WinQuake You can display them as shown below by selecting the tab windows then arrange sielai Bie as x isr imi rI tu mimis ej Start des edo ond UTC Station SSMD1 FIN Leere ern SPS 16 635227 Comment M7 km from SSMD1 Near Coast of Northern Chile Mex Min MEMO HEROS 170c Event Time ext 21 16 33 0 Lat Long 19 0425 70 569W Depth eri 7mi Mag Org 1 15 49 2 P 2128 10 36 S 21 34 32 amp 0 Dift 8 22 240mm Dist 62 324deg 6929 1km 4305 Semi Mag MI JB 35 Start 3 18 14 21 TASI UTC Station LCID 43 713N 116 41W Samples 59905 SPS 16 629662 Comment M7 0 84 Premi rre y Near Coast of Northern Chile MaxMin 1284572905 Tony 300c Event Time 03 16 21 16 33 0 Lat Long 19 8425 70 569W Depth 35km 21 7mi Mag Org 2122198 P 2128 51 90 8 21 34 04 3 Dilf 5 13 230min Dist 32 737deq 3639 6km 2261 5mi Mag MI JB 35 UTC Station WCH 41 7961N B8 459W Samples 18241 SPS 5 053835 Coast of Northern Chile 2452 31 48 X 1 00 09 Y 32c SESW Depth 35km N 62 beppes 6 21 15 44 0 Lat Long 198425 70 ag Org 21 18 44 0 P 2126 13 94 S 13 42 36 Dik E25 322mm Dist 63 SfS Jon POCE Shen 4300 4mi Mag MIT JB 35 64 Loc Scales File Calculate Copy Zoom Options Window Help iu Bj
40. xample you might consider rounding to a better number such as 11 30 e For small earthquakes the P wave should be more or less centered between the start and end of the trace If the P wave occurred at about 11 30 then highlighting should start at 11 00 and end at 12 00 For large earthquakes with 2 or more hours of data the P wave would be left of center perhaps at 20 percent of the time line because there would be a lot more data after the P e All earthquakes are different but most will contain a 20 minute trace a 30 minute trace or up to 180 minutes or more Leave blank space before and after the visible trace on the screen AM If the earthquake has been recorded earlier on a datalogger screen that is no longer visible at the upper left on the computer toolbar pull down the Settings menu Click on Date Time highlight the month and day that are there and enter the month and day of the earthquake using the USGS notification sheet Click OK AmaSeis also has two green arrows on the toolbar to scroll back to an earlier day and a Now button to return to the current time fig 3 With the earthquake highlighted shown in figure 2 in black click on the Extract earthquake icon on the top toolbar green squiggly line that looks like an earthquake trace see figure 3 STZ Eu File i n Settings Control Help Day Week Month Year Now Day Week Month Year Close Extract earthquak
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