User Manual
Contents
1. Depth of i th point in km Note that the first point i 1 is at station the final point i NRP is at the hypocenter IVK i Denote which layer the i th point is in 1 2 3 4 correspond to the upper crust the lower crust the upper mantle and the Pacific plate IWK i Order JUNBAN in Japanese of the segment which includes the i th point The ray between two adjacent discontinuities is called segment here See below for detail Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology 37 Segment of ray KPS 1 2 3 4 5 1P 1 1 1 1 1 2S 2 2 2 2 2 3 PS 2 2 2 1 1 4 SP 1 1 1 2 2 5 1 1 2 2 2 6 P 1 1 1 1 1 7 Pn 1 1 1 1 1 8 Pu 1 1 1 1 1 Figure 4 IWV 8 5 KPS wave type Pu unknown wave type may be Pg P or Pn Matrix IWV 8 5 as given in DATA statement in subroutine TRAVT is shown in Figure 4 The row denotes the wave type KPS 1 2 8 the column denotes the segment number in a ray path IWV KPS IWK I denotes the wave kind P or S wave of I th point in the ray path The wave type KPS of the ray is assigned by the user in the data set common block OBSERV For example for PS wave which converted at UBPP KPS 3 1 When the hypocenter of a deep earthquake is within the Pacific plate there are four segments in the ray path The first IWK i 1 is in the upper crust Lay 1 the second IWK i 2 is in the lower crus2. EPS a small positive value being used to prevent zero to be quotient LAY the layer the hypocenter is in 1 the upper crust the lower crust the upper mantle the Pacific plate AON Tomotools for Windows Trial version November 2004 38 Seismic tomography tools in seismology IHEAD head wave refracted wave or not 1 yes may be P refracted at the Conrad Pn at the Moho or at UBPP when the hypocenter is located slightly above UBPP and the hypocentral distance is relative large e g farther than 400 km 0 no Subroutine BEND Note that for ray segments in the upper and the lower crust IV LE 2 we do not perform pseudo bending i e we assume the two segments to be straight line This approximation is confirmed to be good with error of smaller than 0 01sec because the lengths of the segments in the upper and the lower crust are only about several tens of kilometers and the velocity perturbation is about 6 7 for P wave and about 10 for S wave If you also want to perform pseudo bending for ray segments in the upper and the lower crust lease just remove the statement IF IV LE 2 RETURN and do a little modification in subroutine MINIMUM Subroutine LENGTH In TOMOG3D this subroutine is one of the work horses so we want to find a simple expression for DS the spatial distance between two points in the earth s interior Define PES PE PS RES RE RS PES2 PE PS 2 0 The epicentral di
3. Japan mfarouk sci ehime u ac jp mfarouk30 yahoo com www angelfire com electronic2 mfarouk July 2006 Tomotools for Windows Trial version July 2006
4. Trial version July 2006 Seismic tomography tools in seismology 13 11 Press Start gt The message field will give messages resulted from the different tomography routines The error messages will be given in the message box gt The progress rate of the tomography will be shown in the progress bar gt When the tomography inversion ends the important results will be shown in the message list box The process can be repeated for several file names and several control parameters N C The tomography process once started cannot be interrupted The verbose mode makes the process too slow it is recommended to uncheck the verbose box Do not modify the ResOut2 file resulted from the tomography inversion This file is used for all the coming tools of plotting and cross sections The output files are not protected against being replaced Once Start is pressed all the output files will be replaced without warn Tomotools for Windows Trial version November 2004 14 Seismic tomography tools in seismology 2 Tools menu This menu is used to Read the results written in the ResOut2 Construct cross sections and the corresponding overlay data Calculate the tomography of Poisson s ratio Saturation rate Crack density and Porosity The tools menu can directly use the ResOut2 file constructed by the original code 2 1 ReadRes To read the ResOut2 file of either P or S
5. 06 137 09 137 12 137 15 137 18 137 21 137 24 137 27 137 30 137 33 137 36 137 39 137 42 137 45 137 48 137 51 137 54 137 57 137 60 137 63 137 66 154 91 100 00 0 00 2 00 4 00 7 00 11 00 15 00 20 00 25 00 60 00 N C When using the grid maker mode after confirmation the grids will be written in a grid file named tempgrid txt This file can be used in grid reader mode for further editing of the grid maker grids The maximum allowed number of grids are 99 50 for the horizontal and vertical direction respectively Step 4 Last step of tomography 1 4 Wintomo To start the tomography process using the Control parameters and the modelld file previously constructed above The tomography process is performed through the following tomography dialog box Tomotools for Windows Trial version November 2004 12 Seismic tomography tools in seismology Tomography Tomography Files and Folders Tomography Arguments rs Model 1 p modeltd Edit Browse P wave C S wave sce dataa Edit Browse IV Relocation Verbose ResOut1 Res Edit Browse Control Parameters ResOut2 ResOut Edit Browse 1 D Velocity modei Data Read s EQ 1 IE 2 1000 EN Cancel Progress Message Starting TOMOGRAPHY Fig 4 Tomography dialog box The tomography dialog box consists of all the requirements needed in the tomography routine The only new requirement in this dialog box is the Da
6. In addition the PostOut events do not have a zero depth Here this menu read the hypocenter parameters file and rewrite in a PostOut file format that can be overlaid to the given cross section How to construct the event PostOut file 1 Digitize the cross section line by using Surfer The BLN file of this line is needed Detailed digitization is to be made Extrapolation between points does not exit in this Tomotools version If this is already done go to the next step 2 Click on the Post events menu to open the Post Section dialog box Insert or browse the BLN file name in the section file box 4 Insert or browse the hypocentral parameter file from which the data is to be extracted to fit in cross section The typical example of the hypocentral parameter file and its corresponding format is shown at the end of this section Insert or browse the output PostOut file name in the PostOut box 6 Insert the Limit of extraction in degree All events away from the cross section by the limit value will be extracted See the Post section above 7 Press OK If the BLN and post files are accepted the SecOut file will be constructed 0S Nn An example of the event SecOut file is shown bellow 194 98 8 54 0 9 222 35 8 22 1 2 70 85 5 05 2 3 51 17 10 81 1 0 48 26 9 10 0 6 The data in the above example in sequence are as follows Distance km event depth km and e
7. MBL the number of grids hitted by rays of at least NHITCT If velocity perturbation at a grid say A is the i th element in RHSINI and is the j th element in RHSFIN then we have the relation J INDEX 1 Oppositely if we know the velocity perturbation at A is the j th element in RHSFIN and we want to know which element l th the velocity perturbation at Q is in RHSINI we use the relation JNDEX J Using INDEX and JNDEX we reorder the unknown vector RHS and derivative matrix G and perform inversion then apply inverted velocity perturbation to the original model This is the algorithm of VELADJ Tomotools for Windows Trial version November 2004 40 Seismic tomography tools in seismology Finally let s pay attention to the dimensions of some important matrices In TOMOG3D we assign MST 90 Note that MST is not number of stations but is maximum number of data for a event i e the sum of first P and S wave data and all the later phases data for the event which have the largest number of data among all events in the data set If a study use only first P wave or S wave then MST can be taken to be equal to the number of stations MGD is number of all the grid points MGD NODETOT MGO MGD MST Here assign MG2 3830 3830 1 2 it seems MG2 MGD MGD 1 2 In fact MG2 should be written as MG2 MBL MBL 1 2 For saving memory storage MBL is the number of grids hitted by rays of at least the threshold NHITC
8. Se 11 Wint i iecseecccedidecte ced adiidesseecuebiiedes cas vee 11 How to do tomography seeccceecceecees 12 POOLS Men visisis cass eeisasee ee dees vans eseneed case ee ves eeeesedevs cee adecse 14 ReadReS osor Seeteis sesteee seeds oy nisione ees a E es 14 How to read result ccccccsscscccccccccsecs 15 Poisson Ratio Crack Density Saturation Rate and 16 POEOSILY soeces encerro eaaa ae iee How to calculate the tomography images of Poisson s 16 ratio Crack density Saturation rate and Porosity Section Menu ss oss indeed os cc div cieuee dooce da seeed save de seeeed ose da oseese 18 Local Tele Section seesesesesecccsoccccosecosecosseecseecseo 18 How to construct a cross Section cceeeeees 19 POSt data ced sciesvcticdesceess onetaeo er Eae EEEE EET EEE 20 How to construct a PostOut file 000002 21 Post EVENS 0 0cs ssisesone sees esis cueesaseses siiee0 iea esse esees 22 How to construct a PostOut event file 22 Ext Section cinaidnadisdcondaicasedeseouetanesdebidevonssadaguonvan s 23 How to extract data from a cross section and plot it on 23 the map os cwsiaasdevassvauseselnvs need anes siasesiene pieens sooo oss Plot Meit cese sarees siisna ced eseviciateed aces saseenas cabs sumeseedee ees 24 SUTIOE 5 sacsectsccceteseeetbcadesetseesdeseeteteeevecsdsseemeeseetes 24 Tomotools for Windows Trial version July 2006 Seismic tomography tools in se
9. could be volcanoes distribution digitized maps like coast lines and faults or earthquake distribution The last one will be treated separately in the next section because it requires different I O formats The depth value of all post data here is zero It is supposed that they are projected on the surface of the cross section The Post data menu is responsible for extracting the data from the post files and rewrite in a format PostOut that can be overlaid directly on the cross section This is done by using the Post section dialog box Fig 8 Dialog Post Section Section File file bIn Edit Browse Post file fault bIn Edit Browse PostOut out daf Edit Browse Limits ate OK Cancel Fig 8 Post section dialog box The limit of the cross section is an important parameter in the construction process This value represents the thickness of the cross section slice in degree The description of the Range value is shown in Fig 9 Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology 21 Cross section Main map Fig 9 Schematic description of the Limit value How to construct a PostOut file l W Nn Digitize the cross section line by using Surfer The BLN file of this line is needed Detailed digitization is to be made Extrapolation between points does not exit in this Tomotools version If this is already done go to the next step Clic
10. nodes The depth grids are constructed according to the following relation G LJ K G 1 J K 1 Interval Where G I J K is the grid node of I longitude and J latitude and K depth Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology 11 Grid Reader mode when Grid Reader is checked In which an externally edited grid file is directly used How to construct a modelld file Insert the file name of the station list used in the arrival time data Insert the file name of the output modelld file If using the grid maker mode insert the minimum maximum and intervals of the latitude and longitude of the grid nodes in degree Insert the interval of the depth grids that give the suitable grids The smaller values produce much number of grids If using the grid reader browse or edit a grid file with the same grid format in the original modelld file See appendix for detail Press check to see the grids inserted by either mode Press accept to confirm and construct the modelld file Or press No to repeat inserting grid parameters A typical example of a grid file is as follows 293510 GRIDS 29 08 34 90 34 93 34 96 34 99 35 02 35 05 35 08 35 11 35 14 35 17 35 20 35 23 35 26 35 29 35 32 35 35 35 38 35 41 35 44 35 47 35 50 35 53 35 56 35 59 35 62 35 65 35 68 40 16 113 92 136 70 136 73 136 76 136 79 136 82 136 85 136 88 136 91 136 94 136 97 137 00 137 03 137
11. of the Pacific Plate Note that for crust event dep le 30km the first arrival is Pg wave when epicentral distance DEL is smaller than about 90km and IKPS 1 The first is P when DEL is from 100 135km then IKPS 6 When DEL is larger than about 140 150km the first is Pn wave and IKPS 7 If you can not decide the wave type please just take IKPS to be 8 For deep event DEP gt 50km IKPS 1 for first P arrival and IKPS 2 for first S arrival Common block COMMON OBSERV ISTO MST MEQ SECT MST MEQ KWV MST MEQ amp ISTO SECT KWV WT MST MEQ W MST station number arrival time of wave data wave type Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology 35 WT weight W weight File DATATMG2 which contain arrival time data of several events is provided for reference MODELLING 1 Velocity discontinuities Subroutine HLAY P R H IJK The depth distributions of the Conrad the Moho and the upper boundary of the Pacific plate are represented by power series of latitude and longitude centred at 38 5 140 5 The power series are calculated by subroutine DEPFUN PW RW CG ICM and the output is CG N the corresponding coefficients are given by CFAH in HLAY CFAH 1 CFAH 28 are for the Conrad depth CFAH 29 CFAH 49 are for the Moho depth and CFAH 50 CFAH 77 are for the UBPP depth The coefficients from CFAH 1 to CFAH 49 are obtained by inverting arrival time
12. only the internal 23 2 13 2 grid points are taken to be unknowns for each layer the outer ring of the grid points are used only to interpolate velocities at points between the outer ring and the internal grid points Thus the total number of grid points which are taken to be unknowns is NODETOT NPA 2 NRA 2 NHA 2 NPB 2 NRB 2 NHB 2 NPC 2 NRC 2 NHC 2 NPD 2 NRD 2 NHD 2 User must be careful that for each layer the upper crust lower crust etc the uppermost and lowermost mesh layers and the outer ring of grid points for each mesh layer should be located far away from the internal grid points so that all the ray paths are located within the modelling grid mesh space An example of setting grid meshes is shown in file DATATMG 1 which is used for an application to Tohoku district NE Japan COMMON VOABCD VINAP MPA MRA MHA VINAS MPA MRA MHA amp VINBP MPB MRB MHB VINBS MPB MRB MBHB amp VINCP MPC MRC MHC VINCS MPC MRC MHC amp VINDP MPD MRD MHD VINDS MPD MRD MHD This common block of variables are used to store initial P and S wave velocities at grid points set in layers A B C and D 4 Arrival time data subroutine INPUT4 Common block COMMON STODAT IYMSTO MEQ IDSTO MEQ IHRSTO MEQ COMMON EVENTS MINO MEQ SECO MEQ PHIE MEQ RAME MEQ amp DEPE MEQ EVC 3 MEQ KOBS MEQ Variable Format Description IY 12 year of an earthquake IM 12 Month ID 12 Da
13. than 50 km by 50 km TOMOG3D is expected to perform well for regions with size from several hundred meters to several thousand kilometers partly due to the spherical coordinates system it used Because of these advantages TOMOGSD is considered to be powerful in the 3 D studies in regions such as subduction zones fault zones and continent regions with large depth variations of the Conrad and the Moho discontinuities TOMOG3D is a complex and completely self contained algorithm including one main program and 52 subroutines and requiring 85 kbyte of memory storage Many small tricks are adopted in some subroutines which may be not so easy to understand In the following illustration mainly explain the meanings of the variables scalar vector or matrix and some tricks that used The role of a subroutine played is usually given as comments inserted in the subroutine and will not be repeated here PROGRAM INPUT 1 Control File subroutine INPUT1 Common block COMMON CONTRL NSTS NEQS NOBT NITLOC RMSCUT DVMAX VDAMP amp NHITCT NITMAX RMSTOP STEPL XFAC TLIM NITPB Zhao et al 1989 Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology 31 Parameter Format Description NSTS 14 Number of stations NEQS 14 Number of earthquakes NOBT Total number of data NITLOC 14 3 Maximum number of hypocenter relocations at each iteration R
14. the grid point I J K in layer A The same convention for NPB NRB NHB PNB RNB HNB VELBP VELBS for layer B the lower crust The same for NPC NRC NHC PNC RNC HNC VELCP VELCS for layer C the upper mantle The same for NPD NRD NHD PND RND HND VELDP VELDS for layer D the Pacific plate Note that see file DATATMG1 here NHC 7 i e 7 layers are set in the upper mantle But only the internal 5 layers of grid points are taken to be unknowns the uppermost and the lowermost layers are only used to perform velocity interpolating The same for the upper crust the lower crust and the Pacific plate The configuration of the grid mesh in depth direction is shown in Fig 2 Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology 33 Surface e gt o o 9 Layer A Z i He Conrad e S oo o o 6 6 YY S Layer B ee y aa S Moho S Siab amp o YoY K o o oo o amp wey g o o 6 6 6 6 o Oo ey o 2 o S o o o gt ee Layer C fe ie o o 6 6 0 oe JS oo Pah F o o o o 67 layaD os Q o OF fie K Grid node p Figure2 Velocity model Here NPC 23 NRC 13 i e 23 rows and 13 columns of grid points are set in the latitude and longitude directions respectively for the upper mantle However the same as in the depth direction
15. uses the windows library It does not need any registry or dynamic links DLL files Copy the whole files into the working directory and start to use How to start Before start using this program read carefully the tomography technique of Zhao 1992 Prepare the data in the exact format shown in the Appendices Follow the step by step description shown below Tomotools for Windows Trial version November 2004 Seismic tomography tools in seismology Tomography tools The main window of Tomotools consists of several menus in which the different tools are inserted The tomography tools are classified into four menus 1 Tomography 2 Tools 3 Section 4 Plot 1 Tomography menu 1 D model To insert the initial model used in tomography Control To insert or load the control parameters of the tomography process Model maker To construct the model 1D file used in tomography process Wintomo To perform tomography process for P or S wave 2 Tools menu Read Result To convert the tomography output result into depth files to be used for plotting Poisson Ratio Construct a Poisson s ratio tomography from P and S wave tomography results Crack density Construct a Crack density tomography from P and S wave tomography results Saturation rate Construct a Saturation rate tomography from P and S wave tomography results Porosity Construct a Porosity tomography from P and S wave tomography
16. 3D Written by Prof Dapeng Zhao Seismological Laboratory 252 21 California Institute of Technology Pasadena CA 91125 U S A June 25 1994 wrote this manual when was in Japan in 1989 for the initial version of my tomography program for local and regional earthquake tomography Since then have modified the code considerably e g the inversion part is replaced by the LSQR algorithm the addition of the teleseismic inversion etc But the basic parts like the grid setting the treatment of discontinuities and later phases and 3 D ray tracing are basically the same will try to write an updated version of the manual for the newest version of my tomography program for the joint inversion of local regional and teleseismic event data Observation Center for Prediction of Earthquakes and Volcanic Eruptions Faculty of Science Tohoku University Sendai 980 Japan April 30 1990 Now Geodynamics Research Center GRC Ehime University Japan INTRODUCTION The computer algorithm TOMOG3D written in FORTRAN 77 is designed to use arrival time data from local earthquakes recorded by a network of seismic stations to derive a 3 D seismic velocity model for the crust and the upper mantle beneath the network The conceptual approach parallels the conventional tomography method being composed of the following steps as clearly shown in main part of the program 1 Initialization call subroutine STAT 2 Input Control pa
17. 470 39 43 0 2 0 498 35 05 0 10 498 39 65 0 2 01230 36 03 0 1 01230 41 38 0 20 119 41 610 20 152 37 47 0 1 0 152 43 64 0 2 0 478 38 06 0 1 0 478 44 910 20 508 39 60010 0 0 00000 0 0 00000 0 0 00000 264151 5 46 0 05 35 860 0 13 137 547 0 30 7 100 64 140 0 0 00 1 line is the same as the hypocentral parameter file in cross section tools as follows IY IM ID IH IMIN OSEC DSEC ELAT DLAT ELON DLON DEPTH DDPS NSTM MAG RMS Where IY IM ID year month day of the earthquake IH IMIN Osec DSEC Hour Min Sec of origin time error in origin time Elat Dlat Latitude of earthquake in degree error in lat Elon Dlon Longitude of earthquake in degree error in lon Depth DDPS Depth of earthquake error in depth NSTM The number of reading either P or S or others Mag Magnitude of earthquake RMS Root mean square of location The NSTM readings are listed in the next lines 4 readings per line Each reading consists of the following Station number Arrival time sec Weight Phase code polarity And read as follows READ 4 200 end 999 NSTN J TT J IW J IKPS J IUD J J 1 4 200 FORMAT 4 I4 F6 2 312 Refer to appendix 1 for the phase code IKPS Tomotools for Windows Trial version November 2004 42 Seismic tomography tools in seismology Tomo tools For WINDOWS V1 0 Written by Mohamed Farouk and Dapeng Zhao Geodynamics Research Center GRC Ehime University Matsuyama
18. D which is expected to be more robust and efficient As mentioned in INTRODUCTION TOMOG3D is a complex program including more than 50 subroutines The author doesn t think the program is a perfect one There may exist other techniques and approaches which can make some subroutines more efficient The author strongly advises that all users generate appropriate test cases modelled on the actual data sets to be analyzed to confirm that TOMOG3D will perform adequately when applied to the actual data Thank you for your interest in my TOMOG3D Good luck on your seismic tomography Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology Appendix 2 Input Output formats 41 For the purpose of windows programming and better treating data little changes are done in data format reading The comparison between the old and the now format are given below Subroutine INNPUT3 Tomogla 140 FORMAT 5 11F5 2 Tomotools 140 FORMAT 5 11F6 2 Subroutine INNPUT4 Tomogla 100 FORMAT 5I2 F6 2 F5 2 F7 3 F6 2 F9 3 2F6 2 F5 2 13 F4 1 F5 2 Tomotools 100 FORMAT 5I2 F6 2 F5 2 F7 3 F6 2 F9 3 2F6 2 F5 2 14 F4 1 F5 2 Data file 2 6 4 1 9 28 00 0 02 35 984 0 09 137 566 0 12 5 740 37 21 0 2 0 00 471 29 150 1 0 471 29 85 0 2 0 465 29 92 0 1 0 465 31 120 20 392 33 48 0 1 0 392 37 02 0 2 0 474 37 100 2 0 135 34 33010 1202 34 68 0 1 01202 39 19 0 2 0
19. MSCUT F7 3 0 15 SEC Cutoff value for event rms residual to terminate relocation DVMAX F7 3 0 5 KM S Maximum velocity perturbation per iteration VDAMP F7 3 5 0 Damping factor for velocity NHITCT 14 20 Minimum number of observation of a grid point for it to be included in inversion NITMAX 14 3 Maximum number of velocity inversion step RMSTOP F7 3 0 15 Sec Cutoff for overall rms to terminate velocity inversion step STEPL F7 3 5 0 KM Step length for accumulating velocity partials along ray path only presents in subroutine TTMDER XFAC F7 3 1 0 Convergence enhancement factor for pseudo bending TLIM F7 3 0 002 Sec Cutoff for travel time difference to terminate ray tracing NITPB F7 3 8 Maximum permitted iterations for ray tracing Effectively 60 stations are used Note that in control file only NOBT is not inputted one NOBT is accumulated in subroutine PARSEP 2 Station list subroutine INPUT2 Common block COMMON STATIN PHIS MST RAMS MST HIGS MST STC 3 MST Variable Explanation PHIS N Latitude of N th station in degree RAMS N Longitude of N th station in degree HIGS N Elevation of N th station in kilometer STC 1 N Colatitude of N th station in radian STC 2 N longitude of N th station in radian STC 3 N HIGS N Note that only STC I N I 1 2 3 is used in calculation 3 Initial velocity model subroutine INPUT3 Common bloc
20. Seismic tomography tools User Manual Tomo tools For WINDOWS Mohamed Farouk and Dapeng Zhao Geodynamics Research Center Ehime University mfarouk sci chime u ac jp mfarouk30 yahoo com July 2006 2 Seismic tomography tools in seismology Index Contents Page Preface aernavo eta EEEE ieas EEES 4 Tomotools Description sssssssssesesssesseccseeccsoossssssssssse 5 General strategy sseseseeseessesseeseessesscossesssssesssoseessesseese 5 How to install lt 0 sissscssssvcevssecendvcaaisvensnseviosmeeeesenessabevsduenvere 5 HOW tostart erora nna e E E EEES 5 Tomography tools sissies Qevssctdeiversaisnanead docdcettaausiedeeds 6 Tomography menu eo cease dndcasscsndededersaceassweseesascasouegesones 6 Tools MENU neiitra sbuseedueeeessoseedeuddes se 6 Section MCI oes see irersssssors dtte s sss Ceri s senes s SEEE ESES EENES 6 Plotm n creerea ae aa a a aai T Step DY SlOD cniinne reoi in i EEEE i ieh 7 Tomography menu eesssesseosssessocsssesesososessooosssssososee 7 Step beoreo e e a n a e a Et 7 Controlere iaon EEE h ioei 7 SLA AO A E ATT T 9 1 D model sscsesrioescsicecriceeciccnes sords sieer sai 9 Step I reesen ee dE aE IEN ia sean eae 9 Model Maker csccccccccccssccscccccccsscees 9 Grid maker mode essssesseesosecoseeooe 10 Grid reader mode eesssesssescosesossesoe 10 How to construct a modellid file 4 11 Sep A aneneen seas desc E E ee gale ae
21. T Note that G MG2 is the largest array in TOMOG3D and occupy a large part of the program size SOME REMARKS The program shown here is just the first version of TOMOG3D some extensions or improvements can be easily made in the following respects 1 The depth distributions of discontinuities are fixed during velocity inversion here They can also be included to be unknowns if sufficient data especially those of later phases are available 2 Here the depth distributions of discontinuities are expressed by power series of latitude and longitude i e continuous functions They can also be expressed by grid meshes just like velocity 3 The inversion method used here is the standard damping least square method This method will fail to work when the number of unknowns is very large e g more than 4000 In that case CG type or ART type inversion method should be used 4 Usually the calculation of resolution kernel and standard error for one grid point is the same as one iteration of velocity inversion and the calculation for all grids seems impossible and unnecessary when the number of unknowns is large e g more than 2000 In this case the pulse response technique can be used to calculate the resolution kernel and the Jack knife technique can be used to calculate the standard error The author is performing the extension of TOMOG3D by taking into account that mentioned above and will present in later edition a new version of TOMOG3
22. Windows Trial version November 2004 26 Seismic tomography tools in seismology Notice This program is still under development and the author is not responsible for any inconvenience for invalid results produced by this program For more explanation about this program contact me mfarouk yahoo com Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology 27 Reference Abdelwahed M F 2006 Waveform modeling and tomographic imaging in Japan Islands P hD Thesis Geodynamics Research Center Ehime University Japan Zhao D Hasegawa A Horiuchi S 1992 Tomography imaging of P and S wave velocity structure beneath northeastern Japan J Geophys Res 97 19909 19928 Zhao D Hasegawa A Kanamori H 1994 Deep structure of Japan subduction zone as derived from local regional and teleseismic events J Geophys Res 99 22313 22329 Tomotools for Windows Trial version November 2004 28 Seismic tomography tools in seismology Acknowledgments Great thanks and appreciation to Dapeng Zhao for his permission to use his tomography code in this application Many thanks to all the GRC members Egqlab in special for their help Ehime University with the supervision of Dapeng Zhao provides all the facility to establish this program Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology 29 Appendix 1 User s Manual for TOMOG
23. aker Tomotools for Windows Trial version November 2004 10 Seismic tomography tools in seismology To construct the modelld file used in tomography It does the same job as inidvp routine The modelld file is the same as that of the original tomography It consists of the following Station list The location of the stations used in tomography and labelled in the arrival time data file See appendix for station file format The gird nodes The number and location of the horizontal and vertical grids used in tomography See appendix for the grid nodes file format The initial 3D model The 3D initial values of velocities and perturbations of the grid nodes used in tomography The Model maker Dialog box is used to receive the required information needed to construct the modelld file Unlike the original code the grid nodes are constructed here separately MODEL MAKER Model Maker Stations Fie SEINOR ESI Edit Browse Model File MODEL D 15b Edit Browse Grid parameters Edit grids Minimum Maximum Interval Latitude 35 700 36 000 0 020 oE Browse z Grid Reader Longitude 120 71 120 21 0 020 Depth 0 000 30 000 0400 E Grid Maker Fig 3 Model maker dialog box Two modes of grid constructions are available Grid Maker mode when Grid maker is checked In which the minimum and maximum limits and interval of grids are inserted to automatically construct the grid
24. data from shallow events by Zhao et al 1990 whereas those from CFAH 50 to CFAH 77 are obtained by Dapeng Zhao from representing in power series the result of Hasegawa et al 1983 2 3 D map of grid mesh Giving a point Q in the modelling space firstly we must know which are the eight grid points surrounding Q i e we must find the coordinates of A1 A2 A3 A8 as shown in Fig 3 A2 A4 o l A1 e 13 Q A6 o e A5 ve lt A8 J J A7 Figure 3 Eight grid points surrounding Q These coordinates can be represented by three parameters IP JP KP Assuming Q is located in Layer C the upper mantle for convenience IP index of grid point in latitude direction IP 1 for the southmost grid IP NPC for northmost grid JP index of grid point in longitude direction JP 1 for the westmost grid JP NRC for eastmost grid KP index of grid point in depth direction KP 1 for the uppermost grid KP NHC for lowermost grid Let s define Tomotools for Windows Trial version November 2004 36 Seismic tomography tools in seismology IP1 IP 1 JP1 JP 1 KP1 KP 1 So the coordinates of the eight points surrounding Q can be written as A1 IP JP KP AS IP JP KP1 A2 IP1 JP KP A6 IP1 JP KP1 A3 IP JP1 KP A7 IP JP1 KP1 A4 IP1 JP1 KP A8 IP1 JP1 KP1 For a point Q P R H IP JP KP can be found from subroutines VEL3 and VABPS which need calling subroutines BLDMAP PRHF and INTMAP In BLDMAP the modell
25. esidual to terminate relocation in sec DVMAX Maximum velocity perturbation per iteration in km s VDAMP Damping factor for velocity NHITCT Minimum number of observation of a grid point for it to be included in inversion NITMAX Maximum number of velocity inversion step Tomotools for Windows Trial version November 2004 8 Seismic tomography tools in seismology RMSTOP Cutoff for overall RMS to terminate velocity inversion step STEPL Step length for accumulating velocity partials along ray path TLIM Cutoff for travel time difference to terminate ray tracing in sec NITPB Maximum permitted iterations for ray tracing See appendix for more details In Tomotools these parameters are inserted using the following Control parameters dialog box Control parameters NEQ S 3419 NSTA 1530 NTLOC RMSCUT 0150 DYMAX 0 500 DAMPING 10 000 3 NHITCT 10 NITMAX 1 RMSTOP 0 100 STEPL 2 000 TLIM 0 008 NTPB 8 Fig 1 Control parameters dialog box The control parameters can be inserted directly into the dialog box or imported from a datacp file A datacp file should be in the same original format Otherwise an error message will appear A typical datacp file is as follows 15305107 3 0 150 0 500 8 000 10 1 0 100 2 000 0 008 8 The control parameters can be saved in a datacp file by using the Export button The different parameters a
26. f the Name list file This file is used by the surfer script included with this program to plot the tomography images 2 2 Poisson Ratio Crack Density Saturation Rate and Porosity Calculate the tomography images of the above parameters from the P and S wave tomography result This is done by using the corresponding dialog box How to calculate the tomography images of Poisson s ratio Crack density Saturation rate and Porosity For Poisson s Ratio l Calculate the P and S wave tomography separately following the tomography menu section 2 Click the Poisson Ratio menu to open the Poisson Ratio dialog 3 Browse or insert P wave tomography Resout filename in the Resout P box 4 Browse or insert S wave tomography Resout filename in the Resout S box 5 Browse or insert output Poisson s ratio perturbation file in the Poisson box 6 Insert the suitable limit Range This is the same as the range in the tomography menu not that of the cross sections The default is 11 7 Press OR If the inserted filenames are accepted the Poisson file will be generated and the ReadRes routine will automatically called and generate the perturbation depth files and the name list files See ReadRes menu for detail Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology 17 Poisson Ratio Poisson ResOut P Reste a Browse ResOut S reas Edit Browse Poisson
27. ing space is further subdivided in step length of 0 01 degree in latitude and longitude directions and 1 km in depth direction As shown in subroutine VABPS velocity at Q is obtained from interpolating the velocities at A1 A2 A8 and can be written as VQ VA1 WH 1 VA2 WH 2 VAi WH i VA8 WH 8 where VAi is velocity at grid Ai around Q WH i is the distant weight The nearer to Ai the point Q is the larger WH i is The value of WH i is always in the interval 0 1 Similar to velocity components of velocity gradient dV dP dV dR and dV dH in three direction P R H can also be obtained as shown in subroutine VELD RAY TRACING Subroutine TRAVT INPUT PE Colatitude of hypocenter in radian RE Longitude of hypocenter in radian HE Focal depth of hypocenter in km PS Colatitude of station in radian RS Longitude of station in radian HS Depth of station from sea level in km XFAC Enhancement factor for pseudo bending TACC Cutoff for travel time difference to terminate iteration NITPB Maximum permitted iteration for ray tracing PO Observed travel time OUTPUT DEL Epicentral distance in km VE velocity at hypocenter in km s FST Fastest travel time NRP Number of points which define the final ray path RP Coordinates of the points in the ray path RP 1 i colatitude of i th point in radian RP 2 i longitude of i th point in radian RP 3 i
28. ismology Tomotools limitations cccceessccenescceseccececceeeeceens 25 Parameter limits of Tomotools 25 References esseesseesseeosssossecsseerserosseesseceseeosseosseesseeesese 27 Acknowledgments iii sai daciaisctorcdcvesaadiricaesadeicedieaeeovaniesueanes 28 Appendix 1 User s Manual for TOMOG3D c0sscceseecceeseees 29 Appendix 2 Input Output formats ccceeescceeseeeees cesses 41 Tomotools for Windows Trial version November 2004 4 Seismic tomography tools in seismology Prenc Tomotools description Tomotools is a Fortran Quick win application to perform seismic tomography images using Zhao 1992 code The program consists of all the requirements of the tomography inversion of P and S waves Poisson ratio Saturation rate Crack density and porosity tomography are also provided The Model 1 D and grid net are constructed easily by using the Model maker tool The construction of cross sections and the associated post files like volcanoes faults events etc are all included The tomography results can be sent directly to a visual basic script to be plotted by SURFER Golden software Tomotools preserves the original file formats I O used in Tomog3d code Zhao 1992 Therefore the tomography tools in Tomotools can be applied directly to the output results of the original code without any modifications Tomotools performs the tomography jobs in steps The ou
29. k COMMON VMOD3D NPA NRA NHA PNA MPA RNA MRA HNA MHA VELAP MPA MRA MHA VELAS MPA MRA MHA NPB NRB NHB PNB MPB RNB MRB HNB MHB VELBP MPB MRB MHB VELBS MPB MRB MHB NPC NRC NHC PNC MPC RNC MRC HNC MHC VELCP MPC MRC MHC VELCS MPC MRC MHC NPD NRD NHD PND MPD RND MRD HND MHD VELDP MPD MRD MHD VELDS MPD MRD MHD RO Qo Qo Qo Ro Ro Qo Tomotools for Windows Trial version November 2004 32 Seismic tomography tools in seismology In the names of these variables P R and H mean latitude longitude and depth respectively A B C D denote four layers here the upper crust the lower crust the upper mantle and the Pacific plate respectively P P wave S S wave North P axis latitude e e o 2e 0808808680 West J R axis longitude J e o Grid point o Depth Figure 1 The coordinates system NPA The number of column of grid meshes in latitude direction for layer A the upper crust NRA The number of column of grid meshes in longitude direction for layer A the upper crust NHA The number of layers of grid meshes in depth direction for layer A the upper crust PNA I The latitude of l th row of grid points in layer A RNA J The longitude of J th column of grid points in layer A HNA kK The depth of K th layer of grid points in layer A VELAP I J K P wave velocity at the grid point I J K in layer A VELAS I J K S wave velocity at
30. k on the Post data menu to open the Post Section dialog box Insert or browse the BLN file name in the section file box Insert or browse the desired Post file from which the data is to be extracted to fit in cross section The post file can be either an X Y or BLN data file If X Y data Data should be of two columns separated by a single space representing the longitude and latitude respectively If BLN data A typical BLN format should be used Insert or browse the output PostOut file name in the PostOut box Insert the limit of extraction In the case of faults use a small value 0 01 to reduce the number of projected points Press OK If the BLN and post files are accepted the SecOut file will be constructed An example of the SecOut file is shown bellow Volcanoes 9 36 0 00 15 68 0 00 75 22 0 00 56 17 0 00 The data in this file is simply The distance in km and depth The depth of all the PostOut files is Zero to be projected on the surface Tomotools for Windows Trial version November 2004 22 Seismic tomography tools in seismology 3 3 Post Events This menu is the same as the Post data menu and uses the same dialog box It is used to overlay the earthquake distribution on the cross section in the actual depth and scaled with magnitude value It is separated here because the event file to read is not an X Y or a BLN file but a multi columns data
31. le which contains the depth files needed The procedure of plotting will start When finish the tomography images of the depth files requested will be found plotted in the Surfer workspace Each image is labelled by its depth value Some problem may occur during reading file Check the number of files and the dat files being read The plotting script can be improved by the user The file color3 lvI is the color scale used to plot the images It can be modified according to the limits of the perturbation It should be in the same working directory of the data being read Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology Tomotools limitations 25 Maximum number of horizontal grids 99 Maximum number of depth grids 50 Maximum number Cross section line 1000 Maximum number of event 6000 Maximum number of stations 1600 Tomography process Can not be interrupted Memory Reserve memory for the maximum limits of dimensions Parameter limits of Tomotools PARAMETER MD 120000 MU 180000 MG 120000 80 PARAMETER MEQ 6000 MST 1600 MAX 1000 MDT 2000 PARAMETER MKA 12001 MPA 99 PARAMETER MSEC 1000 JMRA 99 MHA 50 All the above variables are employed similar to the original tomography see appendixl except MSEC which is the maximum number of points in the cross section Last updates Jan 2007 Tomotools for
32. m of the file ResOut2 is ResOut2D010 dat Format of the depth file is as follows First line A string of depth value Next lines Each line consists of the longitude latitude perturbation hit count of the given grid A typical depth file is shown below 20 0 KM 137 66 34 9 1 916 0 05 100 137 66 34 93 0 454 0 01 83 137 66 34 96 0 354 0 01 69 137 66 34 99 0 194 0 01 60 137 66 35 02 0 194 0 01 53 137 66 35 05 0 164 0 01 24 137 66 35 08 0 174 0 01 17 137 66 35 11 0 184 0 01 11 137 66 35 14 0 194 0 01 10 2 Name list file A name list file consists of the number of files constructed and their names This is only used for the plotting purpose This file is requested by the Surfer script to read all the depth files and plot the tomography images simultaneously The Name list file name will be of the same name of ResOut2 file but has the extension NAM Format of the Name list file First line Number of files Tomotools for Windows Trial version November 2004 16 Seismic tomography tools in seismology Next lines Depth file names in order of increasing depth as follows 6 ResOut 15d20SD001 DAT ResOut 15d20SD004 DAT ResOut 15d20SD008 DAT ResOut 15d20SD012 DAT ResOut 15d20SD016 DAT ResOut 15d20SD020 DAT These files can be used independently in any other plotting software for gridding and plotting the tomography images N C Don t modify or change the format o
33. m which the perturbation is to be extracted lt Incase of Local section Local Section menu ResOut file should be resulted from tomotools lt Incase of Tele section Tele Section menu ResOut file should be resulted from Teletmg or Teletmg2 code Zhao et al 1994 Insert or browse the output Cross section file name in the SecRes box Insert the range of perturbation to extract See ReadRes for detail Press OK If the BLN file is accepted the SecRes file will be constructed An example of the SecRes file is shown bellow 0 000 1 000 7 338 5 901 607 0 000 4 000 1 460 5 582 691 0 000 8 000 3 345 6 515 355 0 000 12 000 0 794 6 246 112 0 000 16 000 0 374 6 323 30 5 244 1 000 6 393 5 849 671 5 244 4 000 0 186 5 511 840 5 244 8 000 2 803 6 479 505 5 244 12 000 1 006 6 235 187 5 244 16 000 0 426 6 325 42 Tomotools for Windows Trial version November 2004 20 Seismic tomography tools in seismology 11 506 1 000 5 653 5 810 729 11 506 4 000 1 941 5 393 1034 11 506 8 000 1 880 6 419 711 Data in the SecRes file are in sequence Distance from the starting point in km depth in km perturbation extracted from the Resout file 3D velocity and hit counts To plot the cross section only the first three columns are required 3 2 Post Data The post file is an X Y or BLN file representing any type of data overlaying the cross section tomography images These data
34. poisson Edit Browse 0 00 Range File name list NAM Output file Ddd DAT emea Fig 6 Poisson s ratio dialog box For the calculation of the Saturation rate Crack density and Porosity the above steps are applicable for the corresponding menu N C The range value differs from one parameter to another according to the expected perturbation range The resulted file of all these parameters are treated exactly the same as the Resout data The results of the above menu can be used in other programs for the purpose of plotting Tomotools for Windows Trial version November 2004 18 Seismic tomography tools in seismology 3 Section Menu It is used to construct cross sections across the grid net used The idea of this menu is to use the Blanking BLN file of the Surfer Golden software for the reading of the cross section coordinates The BLN file is the basic of the digitized map Tomotools reads directly the BLN file as the digitization of the profile line needed to be constructed Format of the BLN file is as follows First line Number of points flag Flag here is not important since it takes effect in Surfer only when the BLN file represents a closed area the flag in this case tells either to blank inside 0 or outside 1 the area From this the BLN file takes its name Next lines longitude latitude of the digitized point A typical BLN file is
35. r browse the BLN file name of the data extracted from the section shown in 1 in the Datasec box 5 Insert or browse the output file of the data extracted in the Dataout box 6 Press OK Extract data from section x Extract data from cross section Section File Sec bln Edit Browse Fdasec Extdata bin Edit Browse ExTsec dat i poa Edit Browse Cancel Fig 10 EXT section dialog box If the input files are in the correct format the output file will be constructed Tomotools for Windows Trial version November 2004 24 Seismic tomography tools in seismology 4 Plot Menu This menu is used for plotting the tomography results by using the Basic scripter and the Surfer application The surfer application should be installed in the working machine before using this tool 4 1 Surfer This menu links the Tomotools and the Surfer scripter How to plot 3 4 Tips Click on the Surfer menu to open the Basic scripter A dialog asking for reading result will appear If the depth and the name list files are not yet generated by ReadRes Press YES The Basic scripter will start Open the script file named TOMO PLOT BAS This is given with the Tomotools program It the script is not automatically opened open it from the Scripter Run the Script An Open file dialog box will appear In this dialog box open the name list fi
36. rameter call INPUT1 Station list INPUT2 Initial velocity model INPUT3 Tomotools for Windows Trial version November 2004 30 Seismic tomography tools in seismology Initial hypocentral locations and arrival time data INPUT4 3 For every earthquakes first relocate the hypocenter LOCEQK then calculate derivatives of travel times with respect to hypocentral parameters and medium parameters FORWRD 4 Invert for velocity model adjustments VELADJ and output the inverted velocity model OUTADJ Thus one iteration is accomplished From the travel time residual reduction through the iteration decide if or not to perform the next iteration Code Advantages Albeit its similarity to previous algorithms TOMOG3D has several outstanding advantages Firstly it adopts a quite realistic model that several complicated velocity discontinuities CVDs exist and velocities between these CVDs have variations in three dimension Secondly it contains a robust and efficient 3 D ray tracing technique to calculate travel times and ray paths in such a complex model Thirdly just because of the above two features in addition to first P and S waves TOMOGS3D can combine arrival time data of later phases i e waves converted or reflected at the CVDs important information but being completely thrown away in previous 3 D studies Finally unlike Thurber s SIMUL3 which can only work for arrays extending smaller
37. result 3 Section menu Local Section To construct vertical cross sections from the Local tomographic results Tele Section To construct vertical cross sections from the Teleseismic tomographic results Post Data Construct a PostOut file of data Volcanoes Faults etc to be overlaid on the cross section Post event Construct a PosOut file of events to be overlaid on cross section EXT Section A specific tools for extracting anomalies from a section to construct a model file Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology 4 Plot menu Consists of one submenu Surfer To open the surfer script where the complete tomography images are to be plotted Step by step The following section describes the above menus in steps 1 Tomography menu Follow the next steps to perform tomography Step 1 This step should be first done 1 1 Control To insert the control parameters used in tomography These parameters control most of the tomography processes and should be inserted accurately They are inserted in the original tomography by using the datacp file See appendix for detail These control parameters are as follows Parameter Description NSTA Number of stations NEQS Number of earthquakes NITLOC Maximum number of hypocenter relocations for each iteration RMSCUT Cutoff value for event RMS r
38. s given in the above table should be inserted accurately according to the data used and the tomography conditions The control dialog box entry is given in the tomography dialog box as a quick checking or modifications for the different tomography trials N C Especially the NSTA should be inserted as the exact number of stations exists in the station file Otherwise a run time error will occur Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology The default value of NEQS and NSTA are 1 this is for the checking purpose Step 2 To use the default model or the previously used model skip this step 1 2 1 D model This is the initial model used in the tomography inversion In the original code this is inserted in the subroutines VEL D and HLAY see Appendix for detail To insert the initial model parameter for the four layers used in tomography the following 1 D model dialog box is used 1 D Model 1 D Velocity model S H 3 21 p 400 3 64 D2 19 00 4 30 Cancel Fig 2 The 1 D model dialog box with the default values inserted v4 V2 3 3 93 D3 33 00 v4 Insert the corresponding Vp Vs and depths of the different layers Once press OK the inserted values will be used in the tomography process This can be modified any time before starting tomography Step 3 If the modelld file already exists skip this step 1 3 Model M
39. shown bellow 121 136 5862012 36 4961662 136 68602365 36 2908408 136 80619825 36 0561832 136 94575585 35 8224718 137 0959741 35 5878142 137 18610505 35 3531566 137 3460148 35 090113 137 49623305 34 8554554 137 61640765 34 6700002 137 73658225 34 4164186 137 8267132 34 2593494 137 9061835 34 181761 If the BLN file consists of 2 points delimiting the 2 limits of the cross section Tomotools will interpolate and fill points in between 3 1 Local Tele Cross Section Both local and teleseismic tomography format is support However the current version of TOMOTOOLS can only produce the local tomography results ResOut The cross section is constructed using the Cross Section dialog box Fig 7 Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology 19 Gross Section Cross Section Section File fHe bIn Edit Browse ResOut ResOut Edit Browse secout i SecRes Edit Browse Range 0 00 omea Fig 7 Cross Section dialog box How to construct a cross section l 2 F 4 5 6 7 Digitize the cross section line by using Surfer The BLN file of this line is needed Detailed digitization is to be made Extrapolation between points does not exit in this Tomotools version Click on the Cross section menu to open the Cross Section dialog box Insert or browse the BLN file name in the section file box Insert or browse the ResOut file name fro
40. stance DEL in radian between PE RE HE and PS RS HS can be written as DEL SQRT PES PES RES RES SIN PES2 SIN PES2 According to Bullen amp Bolt at Page 232 in An introduction to the theory of seismology fourth edition 1985 and the error of this formula is less than 1 km if DEL is not longer than 6 5 degree Then using cosine formula and cos DEL 1 2 sin DEL 2 sin DEL 2 and the approximate relation sin DEL 2 DEL 2 when DEL is small the simple expression for DS is obtained TRAVEL TIME DERIVATIVES Subroutine TTMDER When KOPT 0 calculate DTH MST 4 travel time derivatives with respect to hypocentral parameters When KOPT 1 calculate DTM MGO travel time derivatives with respect to medium parameters Note that the medium parameters are the velocity perturbation at every grid points dV V which are arranged as the following Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology 39 dVap Vap dVas Vas dVbp Vbp dVbs Vbs dVcp Vcp dVcs Vcs dVdp Vdp dVds Vds a b c d denote the four layers the upper crust the lower crust the upper mantle and the Pacific plate p s P wave S wave Subroutine NODO Seeing Fig 3 and considering the following six cases for convenience we assume Q is in the upper mantle 1 when KP 1 i e Q is located just beneath the uppermost mesh the grids A1 A2 A3 A4 are ones not included in velocity inversion but just for
41. t Lay 2 the third IWK i 3 in the upper mantle Lay 3 and the fourth IWK i 4 in the Pacific plate Lay 4 So the wave kind of PS wave at the four segments is 2 2 2 1 1 P wave 2 S wave 2 when the hypocenter of a deep earthquake is located slightly above the Pacific plate and the epicentral distance is so large that the wave refracted at UBBP is the first arrival there are five segments in the ray path the former four ones are in Layers 1 2 3 and 4 respectively the fifth segment IWK i 5 one of its ends is hypocenter is in the upper mantle Layer 3 again The wave kind for the five segments is 2 2 2 1 1 For Pn wave KPS 7 1 when hypocenter is in the upper crust there are five segments in Layers 1 2 3 2 1 respectively The wave kinds for the five segments are all 1 P wave 2 When hypocenter is in the lower crust there are four segments in Layers 1 2 3 2 respectively The wave kinds are all 1 P wave PG RG HG VG PA RA HA VA P R H V are middle variables denote the colatitudes longitudes depths and velocities at the points in every segments of the ray path NS 5 NSA 5 number of points in each of the segments of the ray path IV i IWA i i 1 2 5 denote which layer the i th segment is in IH i IHA i i 1 2 5 order JUNBAN in Japanese of segment in the ray path RO radius of the earth taken to b earthquake e 6371 05km here PIDEG pi degree equal to 3 14159265 180 0 0 017453
42. ta file The Data file is the same as the original tomography code written in datala format See appendix 2 How to do tomography 1 Press Control parameters button if it still not loaded or inserted 2 Press 1 D velocity model to change 1 D velocity model if needed 3 Browse or insert the modelld file constructed by this program or by the original inidvp code 4 Browse or insert the data file name specially prepared This consists of the arrival times of the different phases recorded by different stations and different earthquakes Number of events in this file should be greater or equal to NEQS in the control parameters 5 Browse or insert the ResOutl file name This is an output file where the tomography residuals are written when the Verbose is not checked 6 Browse or insert the ResOut2 file name This is the output tomography file It consists of the velocity perturbations resulted from the tomography inversion 7 Insert the first IEQ1 and the last IEQ2 earthquake to read 1 in IEQ2 means read all events in the file 8 Check P or S for doing either P or S tomography 9 Check don t check Relocation to relocate not relocate events 10 Check don t check Verbose to see not see the residuals on the screen If not checked the residuals will be written in the ResOut1 file instead Finally Tomotools for Windows
43. tomography result then extracts the perturbation of every grid layer into separated depth files The following Read Result dialog box is used for this purpose READ RESULT Read result ResOut ResOut Edit Browse 0 00 Range File name list NAM Output file Dddd DAT Cancel Fig 5 Read Result dialog box During the process of reading results the maximum range of perturbations to extract is needed to be used in the limitation and averaging of perturbation This is inserted in the Range box The perturbation values above this range will be equal to Range The perturbation value of a given grid node will be extracted only if the number of hit count of this grid is less than NHITCT in the control parameter Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology 15 How to read result 1 Browse or insert the ResOut2 file name 2 Insert the maximum perturbation range in the Range box 3 Press OR 4 If the ResOut2 file is in the correct format the following files will be constructed 1 Depth files A set of files consists of the perturbations of the grid nodes that have hit counts more than NHITCT one file for every depth layer is constructed Depth file name is the ResOut2 name appended by Dxxx where xxx is the depth value of this layer and has the extension dat Ex The file name of the grid layer 10 k
44. tput of each step is the input of the next Starting from any step is allowed when the required files exist One of the most important features of Tomotools is the generality of the code It is valid for all grid numbers in the allowed limits The control parameters input and output file names and paths are inserted directly in the run time The 1 D velocity model can be changed in any step of the tomography job Tomotools is still in the development stage I need your help to detect bugs and errors to make it perfect Sorry if any inconvenience resulted from this program Have a nice tomography Mohamed Farouk mfarouk sci ehime u ac jp mfarouk30 yahoo com Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology General strategy The general strategy of this manual is to explain how to perform a complete tomography inversion using the different tools included in the Tomotools No need for any other codes or routines to perform the complete tomography process Tomotools constructs all helping file needed The data file should be provided by the user The purpose of this manual is not to describe the typical tomography technique used in the code Refer to Appendix 1 or Zhao 1992 for details The tomography images in this program are plotted through a visual basic script in which all images will be plotted in Surfer program How to install Tomotools is a Quick win application that
45. velocity interpolation so travel time derivatives with respect to the velocities at these grids are not necessary so we call them unnecessary grids UNGs 2 when KP NHC1 i e Q is located just above the lowermost mesh layer the UNGs are A5 A6 A7 A8 3 when JP 1 i e Q is located just east of the westmost column of grids A1 A2 A5 A6 are UNGs 4 when JP NRC1 i e Q is located just west of the eastmost column of grids A3 A4 A7 A8 are UNGs 5 when IP 1 i e Q is located just north of the southmost row of grids A1 A3 A5 A7 are UNGs 6 when IP NPC1 i e Q is located just south of the northmost column of grids A2 A4 A6 A8 are UNGs 7 Through NODO picked out are UNGs travel time derivatives with respect to velocity perturbations at which are not needed VELOCITY INVERSION Subroutine VELADJ For a velocity model which is represented by grid points there are usually many grids which are not hitted by rays Therefore velocity perturbations at these grids can not be resolved and had better be removed from the unknown vector to reduce burdens of memory storage and inversion operations To do this we can reorder the unknown vector from the hit count record of every grids KHIT Two vectors INDEX and JNDEX are used to accomplish this work Suppose the initial unknown vector is RHSINI the dimension is NODETOT all grids except those at the outermost edge of the model and the final unknown vector is RHSFIN the dimension is
46. vent magnitude A typical example of the hypocentral parameter file used in the Post events menu is shown bellow 58 54 39 0 06 35 155 0 14 137 989 0 15 21 92 0 59 39 0 3 0 00 30 26 25 0 09 35 290 0 24 138 150 0 24 40 12 0 81 41 0 6 0 00 10 45 16 0 08 35 029 0 19 136 961 0 25 43 10 0 84 44 1 0 0 00 0 34 38 0 06 35 297 0 22 137 836 0 15 2 73 1 35 41 1 4 0 00 un AA i N oOWNW The data descriptions of the above example in sequence are as follows Tomotools for Windows Trial version July 2006 Seismic tomography tools in seismology 23 TY IM ID IH IMIN OSEC DSEC ELAT DLAT ELON DLON DEPTH DDPS NSTM MAG RMS The writing formats are as follows FORMAT 513 F7 2 F6 2 F8 3 F7 2 F10 3 2F7 2 F6 2 14 f6 1 F6 2 3 4 EXT Section The EXT or extracted section is a special tool to extract data from a section X Depth format and convert it into a Long Lat Depth format to be projected on the corresponding This tool is used for contouring a specific anomaly in a section to the corresponding map This is done through EXT section dialog box shown in fig 10 How to extract data from a cross section and plot it on the map l Digitize the required anomaly from the section file in the form of BLN file X depth This can be done through the digitize tool in SURFER 2 Open the EXT Section dialog 3 Insert or browse the BLN file name in the Section file box 4 Insert o
47. y IH 12 Hour IMIN 12 Minute Tomotools for Windows Trial version November 2004 34 Seismic tomography tools in seismology SECO N F6 2 Second DT F5 2 standard error of SECO N PHIE N F7 3 latitude in degree DPHI F6 3 error of PHIE N in deg RAME N F8 3 longitude in deg DRAM F6 3 error of RAME N in deg DEPE N F6 2 focal depth in km DDEP F5 2 error of DEPE N in km NSTM 13 number of all data for i th event FMG F4 1 Magnitude RMS F5 2 rms travel time residual of the hypocentral location in second Variable Format Description YMSTO l 14 year and month of i th earthquake IDSTO I 12 Day of i th earthquake IHRSTO I 12 Hour of i th earthquake MINO I 12 Minute of i th earthquake EVC 1 1 radian colatitude of i th earthquake EVC 2 1 radian longitude of i th earthquake EVC 3 l Km focal depth of i th earthquake NSTN J 13 station number denoting the station which recorded the datum TT J F6 2 datum arrival time of a seismic wave IKPS J 12 wave type of the datum which was identified by the user when he collects data from seismograms 1 first P wave 2 first S wave 3 PS wave converted at UBPP 4 SP WAVE converted at UBPP 5 SmP wave converted at the Moho 6 P wave refracted at the Conrad 7 Pn wave refracted at the Moho 8 unknown wave which may be Pg P or Pn UBPP the Upper Boundary
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