COMCOT User Manual for version 1.6
Contents
1. ven profile Incident direction i top 2 bt 3 1f 4 rt 4 Wave height meter 0 500 Figure 1 First 36 lines in comcot ctl 3 1 1 Generation information The first block contains general information for a simulation including total run time data output interval type of initial surface profile generation starting type cold start or hot start and the resuming time step For each line parameter should be specified after in Value field Total run time seconds defines the total physical duration to be simulated Time interval for output file unit sec defines the time interval in seconds to output data including free surface elevation and volume flux if specified Specify ini surface 0 FLT 1 File 2 WM 3 LS is used to specify how the initial surface deformation is generated 0 by fault model 1 by a given data file ini_surface dat 2 by incident wave maker 3 by landslide model Start Type 0 Cold start 1 Hot start is used to specify the starting type of a simulation 0 Start a simulation from the very beginning t 0s 1 Start a simulation from a resuming time step where data are previously saved Starting step specified the time step number where a simulation starts from if hot start is used or the time step number when related data are saved for a later restart if cold start is selected 3 1 2 Fault Parameters If in the line Spec2. 1980 For theoretical background and detailed derivations please refer to Liu P L F Woo S B and Cho Y S 1998 Computer programs for tsunami propagation and inundation Cornell University 2 Files required in COMCOT v1 6 The following files are included in this package 1 comcot exe The executable program of COMCOT v1 6 in Windows platform x86 32 bit comcot f90 The source code in Fortran 90 comcot ctl Parameter file for COMCOT v1 6 including information for fault model incident wave maker landslide model and all the grids implemented in a simulation layerX Y dep Input water depth files containing both bathymetry data and topography data for each grid or layer implemented in a simulation XY represents the Identification Number ID of a grid X denotes the level of a grid in the hierarchy of a nested grid system and Y stands for the numbering of this grid in its grid level For example layer23 means that it is a 2 level grid X 2 and it is the 3 one Y 3 in its level In version 1 6 the grid with the largest grid size is the 1 level grid called ayer01 and in one simulation up to 4 regions of sub level grids can be implemented in ayer0 which are layer21 layer22 layer23 and layer24 Generally in one grid region regardless of its level up to 4 sub level grid regions can be nested in Water depth file for each grid is generated by the following code where nx and ny are the x
3. and y dimensions of the grid region and array h nx ny contains the water depth data In a grid region the origin of the coordinate system is situated at the lower left corner with x axis pointing upward northward and y axis pointing rightward eastward open 25 file layerX Y dep status unknown do i 1 ny write 25 10f9 3 h i j i 1 nx enddo close 25 where XY should be replaced by the grid identification number If in a simulation time history input in incident wave maker or landslide model is used additional data files will be required 5 fse dat For time history input in incident wave maker a data file named fse dat must be 6 7 prepared before a simulation starts In fse dat there are two data columns separated by blank space or Tab The first column contains time in seconds and the second column contains the corresponding free surface elevations in meters These two columns must be of the same length i e the same of number of data entries bottom_motion_time dat and bottom_motion_XXXXXX dat if landslide model is used a file named bottom_motion_time dat must exist which contains a column of time sequence in seconds corresponding to snapshots of water depth data in bottom _motion _XXXXXX dat taken at different time due to a landslide The six digits XXXXXX are related to the numbering of data entries in bottom_motion_time dat For example if there are totally 44 data entries in bottom _mo
4. cartesian 1 Governing Eqn 0 linear i nonlinear 0 Grid length dx sphiminute cart meter H o Latitude of south boundary degree St o 1 0 1 H Time step second Use Bottom friction only cart nonlin 0 y 1 n Manning s relative roughness coef bottom fric Output Volume Flux O Yes 1 No p ix 100 iy g 100 Parameters for 2nd level grid layer 21 z aa aaa Run Layer 21 0 Yes 1 No P D 0 Coordinate O spherical l icartesian 1 Governing Eqn 0 linear 1 nonlinear 1 Use Bottom friction only cart nonlin 0 y 1 n 1 is Manning s relative roughness coef bottom fric 2013 Figure 5 Setup for layer01 The meaning of each entry is illustrated as follows Coordinate 0 Spherical I cartesian is used to specify the coordinate system used for 13 layer01 0 Use Spherical coordinates 1 Use Cartesian Coordinates Governing Eqn 0 linear I nonlinear is used to specify the governing equations used for layer01 0 Use linear shallow water equations 1 Use nonlinear shallow water equations It should be noted that if spherical coordinate system is adopted only linear shallow equations can be used Moving boundary scheme associated with runup and inundation calculation in COMCOT v1 6 only works with nonlinear shallow water equations Ar Grid length dx sph minute cart meter is used to specify the grid size Ax of layer01 in meters i
5. from about 5 000 lines to roughly 3 700 lines with enhanced capability efficiency and flexibility However the development of version 1 5 was an on going process With new bugs identified and new features added in the code was modified frequently on different requirements yielding several variations of version 1 5 Numerical simulations performed on this version include 2002 Hua lien tsunami 2003 Algerian tsunami 2004 and 2005 Indian Ocean tsunamis and 2006 Java tsunami For the 2004 Giant Tsunami both runup and inundation were extensively studied in several regions Gradually more and more pressure was brought in the rollout of a new version which should be more stable efficient user friendly and most of all comprise all the features developed before Finally version 1 6 comes In this version a brand new user interface is designed which requires only one parameter file comcot ctl containing all the parameter setups for incident waves fault models landslide model and grid information The grid hierarchy is no longer one to one In each grid level up to 4 sub level grids can be implemented simultaneously Figure 10 Hot start function is also added to allow a simulation being resumed from a specified time step Although lots of tests are made to make sure results consistent with its previous bugs and errors may still exist Please send your feedback to xw46 cornell edu More details for version 1 6 are illustrated in the followi
6. grid region with its parent grid with a grid size ratio 3 Parent grid region Figure 7 An example of nested grid zoom in display of zone 1 and zone2 are shown in figure 8 and figure 9 18 Y_Start 1 ratchet i X_Start 1 X_Start X_Start 1 C ting bound Center of parent grid AER g Center of sub level grid Figure 8 Lower left corner of sub level grid in its parent grid zone 1 in figure 7 m Center of parent grid Connecting boundary f e Center of sub level grid X_End 1 X_End X_End 1 T Ss ee E Coe emcee Cea crt qE haa o a Y_End t e eo e e Figure 9 Upper right corner of sub level grid in its parent grid zone 2 in figure 7 Furthermore an example of a nested grid system is sketched in Figure 10 showing the capability and flexibility of COMCOT v1 6 The two digit number is the grid identification number of that grid region In this example totally one 1 level grid 0 three 2 level grids 21 23 and 24 four 3 level grids 31 32 33 and 34 and four 4 level grids 41 42 43 and 44 are implemented in one simulation 19 Layer 01 Figure 10 Example of nested grid setup This figure is also illustrating the default grid setup in comcot ctl for the attached test example in the release package of COMCOT v1 6
7. specified for bottom friction the roughness coefficients are variable in space The roughness data should be prepared before starting the simulation and the data should be written in the following format open 25 file filename status unknown do j 1 ny write 25 10f9 5 lo fric_vcoef i j 1 nx enddo close 25 And filename should be in the format fric_coef_layerXX dat and XX represents the identification number of the current grid e g 01 for layer01 and 21 for the first 2 4 level grid layer21 nx and ny are the x and y dimension of the current grids Output Volume Flux 0 Yes 1 No is used to determine if the volume flux uh and vh is output for this layer By default COMCOT will only output the free surface elevation ix is used to define the total number of grids in x west to east direction of layer01 x dimension of layer01 Jy is used to define the total number of grids in y south to north direction of layer01 y dimension of layer01 3 1 7 Setup for Sub Level Grids After finishing the parameter setup for ayer0 configuration for all sub level grids ayer21 to layer44 should be set up if one or more sub level grid will be included in a simulation 15 Run Layer 21 0 Yes 1 No ps o Coordinate 0 spherical l icartesian 1 Governing Eqn 0 linear 1 nonlinear 1 Use Bottom friction only cart nonlin 0 y 1 n 1 Manning
8. 0 7 if linear equation is adopted By default the time step of a sub level grid is half of that of its parent grid Grid size of a sub level grid is determined by that of its parent grid and the grid size ratio If for a sub level grid the grid size of its parent grid is 10 0m and the grid size ratio of this sub level grid to its parent is 5 the grid size of this sub level grid is 10 0 5 2 0m 17 3 2 Preparation of water depth data The water depth data including both bathymetry and topography corresponding to grid layerXY is stored in a data file named ayerXY dep where XY is its grid identification number If the matrix h nx ny stores its water depth value at every grid point the data file JaverXY dep can be created by the following scripts open 25 file layerX Y dep status unknown do i 1 ny write 25 10f9 3 h i j i 1 nx enddo close 25 where XY should be replaced by the grid identification number For a sub level grid ID ranging from 2 to 44 the grid dimension nx ny can be determined from the following relationship nx X_End X_Start 1 grid size ratio ny Y_End Y_Start 1 grid size ratio It is also extremely important to make sure that in water depth file bathymetry data takes positive sign and topographical data takes negative sign The coupling between one sub level grid and its parent grid requires lots of efforts and caution The following figures also illustrate the coupling of a
9. 3 3 Cold Start and Hot Start This function is designed for a special purpose In some cases small grid regions of interest are far away from source region and it will take a long time for leading wave of a tsunami to arrive at these regions The time for leading wave traveling from source region to right before entering the small grid regions can be estimated based on water depth and phase speed and furthermore the corresponding time step will be obtained which is specified as the resuming time step for a later restart after Starting step in comcot ctl Then cold start the simulation with all sub level grids turned off After the simulation passes through that specified time step stop the program modify comcot ctl to turn on all the sub level grids required change Start Type to I Hot Start and rerun the simulation For this time the simulation will start from the specified time step with all sub level grids When this function is enabled for the first run three data files for the first level grids layer01 will be created storing free surface elevation and volume flux at the time step specified after Starting step in comcot ctl i e snapshot of layer01 at this step If the time Starting step 20 1000 the three data files will be z7 07 001000 dat m1_01_001000 dat and nl 01 _001000 dat In the next run hot start these files will be loaded in as the initial condition for this restart COMCOT will also automatically sav
10. 5 3 1 4 Incident Wave Maker If in the line Specify ini surface 0 FLT 1 File 2 WM 3 LS 2 is specified wave maker parameters should be given under the block Parameters for Wave Maker in comcot ctl Location of epicenter Latitude degree 36 950 Location of epicenter Longitude degree 3 580 De ee eee eee nnn fesesesssesssssesessssssssssasasssssssssssessses sesesssssssessssesssssseese 5 Wave type 1 Solitary 2 given profile 2 Incident direction litop 2 bt 3 1f 4 rt g 4 Characteristic Wave height meter p 0 500 Characteristic Water depth meter 10 000 F ss2s2sssnn rs Parameters for Submarine Land Slide Values sssss555s255555555555555555555555555555555555 nnn Land Slide Duration in seconds 720 000 Xx start 41 X end 60 Y_start 41 Y end 60 22222 nn Configurations for all grids Values 2222 n Parameters for ist level grid layer 01 Values Figure 3 Parameter setup for wave maker Either solitary waves or a given time history profile can be sent into the numerical domain layer01 through any of the four boundaries Wave type 1 Solitary 2 given profile is used to determine the incident wave type 10 1 Send Solitary wave into the numerical domain ayer0 2 Input a wave profile defined in a time history file fse dat through one boundary 3 Focused solitary wave When using this option incident wave through a boundary will conv
11. COMCOT User Manual Version 1 6 Drafted on Sep 19 2006 Updated on Feb 26 2007 School of Civil and Environmental Engineering Cornell University Ithaca NY 14853 USA Journey of COMCOT COMCOT COrnell Multigrid COupled Tsunami model originated from the work of S N Seo based on Shuto s model Aug 10 1993 and Yongsik Cho arranged version 1 0 Aug 10 1993 A significant improvement was achieved by Seung Buhm Woo 1999 3 Many features including nonlinear model Automatic Initial surface interpolation general grid matching and user interface were introduced and finally formed version 1 4 However at this stage the code was still not well organized and there were limitations in many aspects e g grid setup initial condition especially efficiency capability and flexibility The code at that time was written in Fortran 77 and inconveniently needed to be recompiled for each new simulation Many achievements were made on COMCOT during this period such as the successful simulations of 1960 Chile Tsunami and 1986 Taiwan Hua lien tsunami involving the calculations of runup and inundation The coming of Fortran 90 gave a new power to the programming of this code With the helps of many others especially Tom Logan ARSC Steven Lantz Cornell and Philip L F Liu Cornell further improvements and modifications were introduced by Xiaoming Wang 2003 which yielded version 1 5 The most significant progress is the migra
12. cripts will be able to read the data in a output data file F_ AB dddddd dat into a predefined matrix B nx ny open 25 file F_XY_dddddd dat status unknown do i 1 ny read 25 15f9 3 BG j i 1 nx 21 enddo close 25 oy where F denotes z m or n AB represents Identification Number of a grid region and dddddd stands for the time step at which the data is written In addition if the switch Output Volume Flux is set to 2 neither water surface elevation nor fluxes will be out 22 5 Example A set of sample data files is included in the package of COMCOT v1 6 The default configuration in comcot ctl defines a nested grid setup illustrated in Figure 10 The dimensions for all grid regions are all the same 00 00 The grid size and time step for ayer0 are 10 0m and 0 025s respectively A constant water depth 0 0m is used and a solitary wave with amplitude 0 5 m is sent into J ayer0 through its lower boundary The other three boundaries use open boundary condition Two snapshots of ayer0 at t 50s and t 100s are shown in Figure 11 0 0 100 200 300 400 500 600 700 800 900 0 100 200 300 400 500 600 700 800 900 Figure 11 Wave field Snapshots of layer01 23
13. e resuming snapshots of all grids every 1000 time steps for later start To resume from any of these saved snapshots changing the start_type option to 2 and specifying the starting time step after starting step the simulation will start from the specified time step 4 Output Data Generally only the free surface elevation will be output in data files named in the form z AB dddddd dat where z stands for free surface elevation two digits AB denote the corresponding grid identification number and the six digits dddddd corresponds to the time step number when the data is output Therefore data file z AB dddddd dat stores the free surface elevation at all grid points in grid region layerAB at time step dddddd For example z 23 001234 dat stores the free surface elevation at all grid points of ayer23 at time step 1234 It should be mentioned that the total number of time steps required for a simulation and also time step number for data output are also calculated based on the time step 4t of ayer0 For example if 0 5s time step is used for ayer0 the time step number 234 corresponds to a physical time t 234 0 5 617 0s However if the switch Output Volume Flux is set to 0 for layerAB two additional types of data files m_ AB dddddd dat and n_AB_ dddddd dat will be created storing volume flux data in x direction and y direction respectively at all the grid points in JayerAB at time step dddddd The following s
14. erge to a specified location focus Two additional parameters will be asked for when the program starts x and y coordinates of the focus in ayer0 Incident direction 1 top 2 bt 3 lf 4 rt defines which boundary the wave is sent through 1 waves come from the top boundary of the domain waves come from the bottom boundary of the domain waves come from the left boundary of the domain A WwW N waves come from the right boundary of the domain 5 Oblique incident wave When using this option an oblique wave will be sent into the numerical domain through boundaries The oblique angle will be required after the program starts The angle ranges is measured from the northward upward to the incident direction ranging from 0 to 360 Characteristic Wave height specifies the characteristic wave height of the incident wave only effective when solitary wave is sent in Characteristic Water depth specifies the characteristic water depth which is effective for both wave types This value is used to calculate volume flux associated with incident waves based on linear shallow water wave theory 3 1 5 Parameters for Submarine Landslide Model If in the line Specify ini surface 0 FLT 1 File 2 WM 3 LS 3 is specified landslide parameters should be given under the block Parameters for Submarine Land Slide in comcot ctl Parameters for ist level grid layer 01 feeneessenensnnessssn
15. essasssnssseessessssssssses sesssessssssssssesesssssssssses Coordinate O spherical 1 cartesian Governing Eqn 0 linear i nonlinear 0 Grid lengthi dx sph minute cart meter D 10 0 Latitude of south boundary degree 5 0 Time step second 0 05 Use Bottom friction only cart nonlin 0 y 1 n 1 Manning s relative roughness coef bottom fric 0 013 Output Volume Flux O Yes 1 No p 1 ix 100 iy o 100 Figure 4 Parameter setup for submarine landslide model Compared to the dimension of the 1 level grid i e Jayer0 landslide generally occurs within a small confined region In COMCOT v1 6 during a submarine landslide water depth in that small confined region is required to be sampled at locations coincident with grids of layer01 at the time given in bottom _motion_time dat which should be prepared by user The position of the small landslide region is defined in ayer0 in terms of its grid indices xX _Start defines the left west boundary of the landslide region expressed in terms of the grid index of ayer0 in x direction X End defines the right east boundary of the landslide region expressed in terms of the grid index of ayer0 in x direction Y Start defines the lower south boundary of the landslide region expressed in terms of the grid index of ayer0 in y direction Y End defines the upper north boundary of the landslide region expressed in terms of the gr
16. f using Cartesian Coordinates or in minutes if using Spherical Coordinates Latitude of south boundary gives the latitude of south lower boundary of layer01 This parameter is not effective if all the grids are using Cartesian coordinates and the fault model is not chosen in a simulation Time step defines the time step At used for the 1 level grid layer01 in a simulation The grid size Ax and time step At should satisfy Courant Condition to make the program stable CAt lt where C is the phase speed which can be evaluated as C 4 gh g is the gravity acceleration g 9 81m s and h is the characteristic water depth should choose the maximum water depth which will yield the largest C For COMCOT c lt 0 5 is recommended may allow up to c lt 0 7 if linear equation is adopted Use Bottom friction only cart nonlin 0 y 1 n is used to determine if bottom friction is used in this grid 0 With bottom friction 14 1 Without bottom friction 2 Include bottom friction with variable roughness coefficients Bottom friction is evaluated with Manning s Equation and only works when nonlinear Shallow Water Equations are used When the option 0 is selected the roughness coefficient is a constant uniform throughout the grids which is specified at the entry below Manning s relative roughness coef bottom fric defines the Manning s coefficient n When the option 2 is
17. id index of ayer0 in y direction The grid dimension of landslide region can be obtained from nx X_End X_Start 1 ny Y_End Y Start 1 For each time given in bottom _motion_time dat there is a data file bottom_motion_XXXXXX dat storing a snapshot of water depth at every grid in the landslide 12 region at that time The six digits XXXXXX are related to the numbering of data entries in bottom_motion_time dat For example if there are totally 44 data entries in bottom_motion_time dat then XXXXXX is numbering from 000001 to 000044 Then bottom_motion_000027 dat contains the snapshot of water depth at the time given at entry 27 i e line 27 in bottom_motion_time dat during a landslide event The snapshot file e g bottom_motion_000027 dat can be generated via the following code where nx and ny are grid dimensions in the x and y directions of landslide region and matrix h nx ny contains water depth at every grid in the landslide region defined by X Start X_End Y Start and Y End open 25 file bottom_motion_000027 dat status unknown do j 1 ny write 25 F10 5 h i j i 1 nx enddo close 25 3 1 6 Grid setup for Layer01 In comcot ctl configuration for grids of all levels follows the parameter block of landslide model The first block contains configurations for the 1 level grid the largest grid region layer01 ee annn Configurations for all grids Values Coordinate O spherical 1
18. ify ini surface 0 FLT 1 File 2 WM 3 LS 0 is selected fault parameters should be given under the block Parameters for Fault Model in comcot ctl Start Type O Cold start 1 Hot start i o Starting step 1000 Focal Depthifrom see floor to epicenter meter 10000 000 Length of source area meter 36500 000 Width of source area meter 138900 000 Dislocation of fault plate meter 1 000 Strike direction theta degree 57 000 Dip angle delta degree 44 000 Slip angle lamda degree 71 000 Origin of computation Latitude degree 36 000 Origin of computation Longitude degree 0 979 Location of epicenter Latitude degree 36 950 Location of epicenter Longitude degree 3 580 PE Parameters for Wave Maker Values sssss5555555555555555555555555555555555555555 nnn Wave type 1 Solitary 2 given profile 2 Incident direction 1litop 2 bt 3 1f 4 rt 4 Wave height meter 0 500 Figure 2 specify fault parameters Fault parameters for a specific earthquake Focal Depth Distance measured vertically from the focus to earth surface Length of source area Length of the rectangular fault plane Width of source area Width of the rectangular fault plane Dislocation of fault plate Relative Dislocation between foot block and hanging block on the fault plane Strike direction theta Strike direction of the fault plane measured from the north to the fault line with fa
19. ines the position of right east boundary of this sub level grid region in its parent grid expressed in terms of x indices of its parent grid Y_ Start defines the position of lower south boundary of this sub level grid region in 16 its parent grid expressed in terms of y indices of its parent grid Y End defines the position of upper north boundary of this sub level grid region in its parent grid expressed in terms of y indices of its parent grid Therefore this rectangular sub level grid region is outlined by its four corners in its parent grid x_start y_start x_end y_start x_end y_end and x_start y_end The total number of grids in x and y directions can be calculated as nx X_End X_Start 1 grid size ratio ny Y_End Y_Start 1 grid size ratio system ranging from 2 to 4 The second digit ranging from 1 to 4 stands for the numbing of the grid region in its grid level The grid level is defined in terms of the largest grid region the 1 level grid named ayer0 Grid regions directly nested in the 1 level grids Jayer0 are called 2 level grids And grid regions directly nested in a 2 level grids e g Jayer21 are called 3 level grids so on and so forth Up to 4 grid levels can be defined in COMCOT v1 6 In each sub level grid to make the program stable the Courant Condition CAt lt c Ax should also be satisfied and c lt 0 5 is recommended may allow up to c lt
20. ng sections in this document Xiaoming Wang Sep 20 2006 1 Introduction COMCOT adopts staggered leap frog finite difference schemes to solve Shallow Water Equations A nested grid system dynamically coupled up to four regions which will be referred to as layers with different grid resolution is adopted in the model to fulfill the need for tsunami simulations in different scales Nested grid system means in a region of one grid size there is one or more regions with smaller grid sizes situated in which eventually forms a hierarchy of grids or grid levels The region with largest grid size is called 1 level grid and all the grid regions directly nested in the 1 level grid are called 2 level grids so on and so forth In one grid region up to 4 sub level grid regions can be defined It should be noted that in one grid region a uniform grid size is adopted in COMCOT Spherical or Cartesian coordinate system as well as either linear or nonlinear version of governing equations can be chosen for each region The initial free surface deformation due to a submarine earthquake is assumed the same as the vertical displacement of the sea floor as long as the uplift motion is much faster than the wave propagation otherwise submarine landslide model should be used to include transient motion effect For a given earthquake the displacement of seafloor is determined from a linear elastic dislocation theory Manshinha and Smylie 1971 or Okada
21. s relative roughness coef bottom fric 0 013 Output Volume Flux O Yes 1 No 1 Grid Size Ratio of LayerO1 to Layer21 0 5 X start 41 X end 60 Y_start 41 Y_end 60 Grid Identification Number DONNOT CHANGE 21 Parent Grid s ID Number 1 Figure 6 Setup for layer21 The entries are identical in all the parameter blocks for sub level grids Among these parameters two are important to the determination of position of a grid in the hierarchy of grid levels in a nested grid system One is Grid Identification Number which distinguishes current grid region from the others The other one is Parent Grid s ID Number determining which grid is its parent grid upper level grid where the grid is directly situated The other parameters different from those of layer01 are explained as follows taking ayer2 as an example Run Layer 21 0 Yes 1 No determines if this grid region is included in a simulation 0 Yes included in this simulation 1 No not included in this simulation Grid Size Ratio of Layer01 to Layer21 defines the grid size ratio of this grid region layer21 to its parent grid ayer01 For example if this value is 5 the area of one ayer0 grid will equal to that of 25 layer21 grids 5X 5 xX _Start defines the position of left west boundary of this sub level grid region in its parent grid expressed in terms of x indices of its parent grid X End def
22. ter surface displacement is interpolated into all sub level grids 3 Preparation of Input files The user should prepare the topographic information and focal parameters for the specific tsunami simulation The detailed information on preparing these files as well as a further explanation of the variable in input data files is given in the follows sections 3 1 Preparation of comcot ctl comcot ctl contains all the control parameters for a simulation including setup for incident wave maker landslide fault model and nested grids This file is written in ASCII format and can be edited in any TXT capable editor e g wordpad UltraEdit HHAHHRHHH HHH HEHHRAAH ARH ARHARAARAAEAAH AEH AAARH ARES Control file for COMCOT program v1 6 HHRHHHHAAARHRARHH RARER AARRR RARER AARRR AAR R ARRAS 4 Time interval for output file unit sec 1 0 Start Type 0 Cold start 1 Hot start o Starting step If hot start 3 1000 Focal Depth from see floor to epicenter meter 10000 000 Length of source area meter 36500 000 Width of source area meter 18900 000 Dislocation of fault plate meter 1 000 Strike direction theta degree 57 000 Dip angle delta degree 44 000 Slip angle lamda degree 71 000 Origin of computation Latitude degree 36 000 Origin of computation Longitude degree 0 979 Location of epicenter Latitude degree 36 950 Location of epicenter Longitude degree 3 580
23. tion from Fortran 77 to Fortran 90 allowing dynamic allocation of memory Parameter module was introduced making the code much neat and readable And subroutines dealing with nonlinear equations were also optimized to get a better efficiency by Tom Logan ARSC 2003 Furthermore many redundant or unnecessary subroutines were either removed or combined together including subroutines pqstill pqtotal mass mass_s mass_c moment momt_s momt_c ini_mvd jnzoa jngoa et_o prt et_a prt et _b prt etc Some subroutines were renovated or completely rewritten including subroutines involving parameter input and data output Old parameter setup files comcot_common inc and comcot_v_1 4 inc were removed and their data entries were incorporated into comcot_v_1 4 ctl In addition new features were added in version 1 5 like Cartesian coordinate support for the 1 level grid layer 1 submarine landslide model Okada s fault model given static initial surface profile given time history data input in incident wave maker used for benchmark problem 2 in Catalina Workshop 2003 Unlike its previous versions which only allow one to one grid hierarchy each grid can contain only one sub level grid in version 1 5 1 level grid layer 1 can employ up to 4 2 level grids layer 2s although sub level grids still use one to one grid hierarchy This gives more flexibility for a simulation if multiple sub regions are of interest The code was compacted
24. tion_time dat then XXXXXX is numbering from 000001 to 000044 Then bottom_motion_000027 dat contains the snapshot of water depth at the time given at entry 27 i e line 27 in bottom_motion_time dat during a landslide event Remember that water depth changes continuously during landslide A snapshot of water depth at time means the instantaneous water depth at every grid point at that given time during the landslide event bottom _motion XXXXXX dat can be generated via the following code where nx and ny are dimensions in the x and y directions of landslide region and h nx ny contains the water depth open 25 file bottom motion XXXXXX dat status unknown do j l ny write 25 F10 5 h i j 1 nx enddo close 25 where XXXXXX should be replaced by the numbering of a snapshot ini_surface dat If initial water surface displacement is obtained from a given data file a data file named ini_surface dat should be prepared before run In ini_surface dat special water surface deformation profile can be described as the initial condition of a simulation This data file can be created via the following code where deform nx ny contains the water surface displacement at each grid point and nx ny are dimensions of 1 level grid open 25 file ini_surface dat status unknown do j 1 ny write 25 15f8 3 deform i j 1 nx enddo close 25 Then at the beginning of a simulation starts this initial wa
25. ult plane on the right hand side Dip angle delta Angle between earth surface and the fault plane Slip angle lamda Angle measured counter clock wise from the fault line to the direction of relative motion of hanging block on the fault plane Origin of computation Latitude degree Latitude of the lower left i e southeast comer grid in the 1 level grid layer01 Origin of computation Longitude degree Longitude of the lower left i e southeast comer grid in the 1 level grid layer01 Location of epicenter Latitude degree Latitude of the epicenter of an earthquake Location of epicenter Longitude degree Latitude of the epicenter of an earthquake If fault model is selected a data file named ini_surface dat will be created using the same format given in section 3 1 3 containing the initial surface displacement at every grid of layer01 calculated from the built in fault model 3 1 3 Given Initial Surface Displacement If in the line Specify ini surface 0 FLT 1 File 2 WM 3 LS I is specified which means the initial water surface displacement is specified in an external data file a data file named ini_surface dat must be prepared If an array deform nx ny stores water elevation at every grid in ayer0 this file can be created via following scripts open 25 file ini_surface dat status unknown do j l ny write 25 15f8 3 deform i j i 1 nx enddo close 2
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