# Binder_ew Configuration File Commands

(last revised October 17, 2008)
Page Index:
1. Example configuration file
2. Functional command listing
3. Alphabetic command listing & description

On startup, binder_ew reads the configuration file named on the command-line. Commands in this file set up all parameters used in stacking picks, locating events, and associating phases with events. In the control file, lines may begin with a valid binder_ew command (listed below) or with one of 2 special characters:

>     #  marks the line as a comment (example: # This is a comment).

>     @  allows control files to be nested; one control file can be
>        accessed from another with the command "@" followed by
>        a string representing the path name of the next control file
>        (example: @model.d).

Command names must be typed in the control file exactly as shown in this document (upper/lower case matters!).

## 1. EXAMPLE CONFIGURATION FILE

    # This is binder_ew's parameter file!
    #
    MyModuleId   MOD_BINDER    # module id for this instance of binder_ew
    RingName     PICK_RING     # transport ring for I/O
    LogFile      1             # 0 to completely turn off disk log file
    HeartbeatInt 30            # Seconds between heartbeats

    # List the message logos to grab from transport ring
    #              Installation       Module       Message Type
    GetPicksFrom   INST_WILDCARD    MOD_WILDCARD    # pick2k

    # Set level of output for writing log file
    #
    log_stack          # comment out to turn of grid-stack logging
    hypcode    7

    # Load station list
    #
    maxsite 2000
    site_file "calsta.hinv.qa"

    # Load Central California crustal model
    #
    @ncal_model.d

    # Define the association grid.  Set stacking parameters.
    #
    dspace          4.0
    grdlat         32.5             43.0
    grdlon       -125.0           -114.5
    grdz            0.0             20.0
    rstack 100.0
    tstack 0.65
    stack  50
    thresh 18
    focus  30
    grid_wt 0 4
    grid_wt 1 3
    grid_wt 2 2
    grid_wt 3 1

    # Set parameters for associating picks with active hypocenters
    #
    rAvg_Factor 7.0
    taper   0.0     1.0
    taper   50.0    1.0
    taper   200.0   2.5
    taper   400.0   4.5
    # bfh: 11/5/94: "variable taper" proportional to Origin Time Uncertainty:
    # Set both to 0.0 to get Carl's original distance taper only.
    taper_OT 2.0 1.0
    t_dif   -3.0   120.

    # Set parameters for locating events
    #
    wt 0 1.0
    wt 1 0.5
    wt 2 0.25
    wt 3 0.125
    ph P  1.0
    ph Pn 0.5
    ph Pg 0.5
    r_max  400.0
    zrange 1.0 30.0
    MaxStep 25.0  5.0
    MinXYZstep 0.1
    MaxIter 4
    MaxDeltaRms 1.0001
    locate_eq  25   2
    locate_eq  50   4
    locate_eq  75   8
    locate_eq 100  16

    # Set parameters for assessing groups of picks
    # with Bill Ellsworth's resampling technique:
    assess_pk  8  12
    maxtrial   500
    maxwt      3
    v_halfspace  5.0
    residual_cut  5.0  10.0
    #log_accepted

    # Load in the next valid quake sequence number
    #
    @quake_id.d

    # end of parameter file

## 2. FUNCTIONAL COMMAND LISTING

Below are the commands recognized by binder_ew, grouped by the function they influence. A few of the commands are marked "required"; they describe the Earthworm system setup and network and stacking parameters; these variables have no default values. The required commands must be specified in the control file in order for binder_ew to operate.

    	Earthworm system setup:
      		GetPicksFrom	required
     		MyModuleId	required
    		RingName	required
    		BufferRing	required

    	Seismic network/model definition:
    		lay 		required
    		psratio
    		site 		\  site list required; specify with
    		site_file 	/  either "site" or "site_file"
    		maxsite

    	Phase stacking:
    		dspace		required
    		grdlat    	required
    		grdlon    	required
    		grdz		required
    		thresh		required
    		define_glitch
    		focus
    		grid_wt
    		grid_wt_instid
    		next_id  (@quake_id.d)
    		EventFileId (to point to quake_id file in case of multiple binder_ew's)
    		rstack
    		stack
    		tstack
    		rmsgrid		no longer used

    	Event location:
    		FixDepth
    		locate_eq
    		MaxIter
    		MaxDeltaRms
    		maxpix
    		MaxStep
    		MinXYZstep
    		ph
    		r_max
    		rmscut
    		wt
    		zrange

    	Phase association:
    		rAvg_Factor
    		t_dif
    		taper
    		taper_OT

    	Pick-group assessment:
    		assess_pk
    		maxwt
    		maxtrial
    		residual_cut
    		v_halfspace

    	Output control:
    		LogFile		required
    		hypcode
    		log_accepted
    		log_stack
    		ray
    		raytst
    		region

## 3. ALPHABETIC COMMAND LISTING & DESCRIPTION

In the following section, all configuration file commands are listed in alphabetical order. Listed along with the command (bold-type) are its arguments (in red), the name of the subroutine that processes the command, and the function within the module that the command influences. A detailed description of the command and is also given. Default values and the values used by Calnet are listed after each command description.

    command arg1				processed by		function

    assess_pk minpk maxpk			assess_com		pick assess

> Defines the range for assessing a group of picks using the resampling technique of Bill Ellsworth. When an event has between minpk and maxpk (inclusive) picks associated with it, its pick set will be assessed before the event is relocated. If an event stacks with more than maxpk picks, its picks will be assessed at least once. Pick-assessment is a multiple pass process based on Rex Allen's pick associator. First, the set of picks is examined for glitches. Then the exact, four-station hypocenter solution method of Ingelada and resampling (four picks at a time) are used to determine the station set that is consistent with an earthquake hypocenter. A first pass samples from the earliest (up to 25) P-phase picks which meet the testing criteria; this pass is used to winnow the data to arrivals with median residuals below a cutoff value. A second pass resamples the winnowed data to determine the trial hypocenter. If any picks are rejected as glitches or outliers, they are freed to restack or reassociate. To turn off pick-assessing totally, set minpk and maxpk to zero. Related commands include "define_glitch", "maxtrial", "maxwt", "residual_cut", "v_halfspace".

>     Default:  assess_pk 6 12                Calnet:  assess_pk 8 12

    BufferRing ring				bndr_config		Earthworm setup

Tells binder_ew which shared memory region to use for private ring buffering of picks. ring is a character string (valid strings are listed in earthworm.d) that relates (in earthworm.d) to a unique number for the key to the shared memory region. This rings name must be declared in earthworm.d BUT MOST NOT BE LISTED in startstop.d!!!

    Default:  none				Calnet:  BufferRing BINDER_EW_RING

    define_glitch npick nsec		grid_com		stack

> Sets up the definition of a glitch for filtering arrivals before stacking them. A glitch is defined as at least npick arrivals within nsec seconds. Picks that belong to such a glitch are NOT used in the stacking process. If you want to turn off pre-stack glitch filtering (ie, to make binder_ew stack every pick), set npick to zero (example "define_glitch 0 0.0"). This same glitch definition is used in the pick-assessing process (see command "assess_pk") to recognise glitch-picks that have associated with an event (after it is stacked) and to remove them.
> Note: nsec should be set slightly larger than an integer multiple of the pick-timing resolution to avoid missing glitches due to round-off errors in floating point arithmetic (for example, our picks are reported to the nearest 0.01 seconds, so we set nsec to 0.035 sec instead of 0.03 sec).

>     Default:  define_glitch 4 0.035          Calnet:  define_glitch 4 0.035

    dspace dspace				grid_com		stack

> Defines the side-length (dspace in km) of a cell in the stacking volume. The same spatial resolution is used for latitude, longitude and depth. Decreasing cell size increases the time required for stacking as the third power, so adjust these values judiciously. The cell size you choose may also depend on your network station spacing; if too many stations fall within the same grid-cell, stacks may often be null- focused.

>     Default:  none                          Calnet:  dspace  4.0

    EventIDFile filename_of_quake_id			bind_com			bind

This allows the operator to run multiple binder_ew instances and have each use a different quake_id file.

    Default:  Not SET,  uses quake_id.d by default then

    FixDepth dmin trialz			hyp_com			location

> Sets the trial depth (km) to use for earthquakes which have no nearby stations. If an earthquake has no picks within dmin km, set its depth to trialz km and locate it with a fixed-depth solution. This prevents events with no depth resolution from flailing.

>     Default:  FixDepth 50.0 8.0             Calnet:  FixDepth 50.0 8.0

    focus nfocus				grid_com		stack

> Defines how focused a stack must be to consider declaring a new quake. A stack must have no more than nfocus cells in its maximum-count list and the maximum count value must be greater than or equal to mthresh (see "thresh" command) in order to declare a new event. Since the trial hypocenter is calculated by averaging the center positions of all the cells in the maximum-count list, a larger nfocus will increase the probability of a poor starting location (which has its own attendant problems). A smaller nfocus value, however, will tend to reject distant events. The optimal value for nfocus may also depend on the grid granularity ("dspace" command). Considerable experimentation may be required to determine an optimum value for any specific network.

>     Default:  focus 5                       Calnet:  focus 30

    GetPicksFrom inst mod_id		bndr_config		Earthworm setup

> Controls the picks input to binder_ew. Binder_ew will only process picks that come from module mod_id at installation inst. inst and mod_id are character strings (valid strings are listed in earthworm.h/earthworm.d) which are related to single-byte numbers that uniquely identify each installation and module. Up to 2 "GetPicksFrom" commands may be issued; wildcards (INST_WILDCARD and MOD_WILDCARD) will force binder_ew to process all picks, regardless of their place of origin.
> Note: both binder_ew and eqproc should be set to listen to the same pick source(s)!

>     Default:  none
>     Calnet:   GetPicksFrom  INST_WILDCARD MOD_WILDCARD

    grdlat lat1 lat2			grid_com		stack

> Defines the latitude range (decimal degrees; positive to the north) of the volume containing all trial stacking hypocenters (set the latitude boundaries of the regional grid). Once an event is stacked, it may relocate outside of this range, and it will continue to associate picks correctly.

>     Default:  none                          Calnet:  grdlat   32.5   43.0

    grdlon lon1 lon2			grid_com		stack

> Defines the longitude range (decimal degrees; positive to the east) of the volume containing all trial stacking hypocenters (set the longitude boundaries of the regional grid). Once an event is stacked, it may relocate outside of this range, and it will continue to associate picks correctly.

>     Default:  none                          Calnet:  grdlon -125.0 -114.5

    grdz z1 z2				grid_com		stack

> Defines the depth range (km; positive down) of the volume containing all trial stacking hypocenters (set the depth boundaries of the regional grid). The range from z1+(dspace/2) to z2-(dspace/2) must not be greater than the depth range specified in the "zrange" command; otherwise, events may stack outside of the zrange limit and this could cause locator logic errors.

>     Default:  none                          Calnet:  grdz    0.0   20.0

    grid_wt quality increment		grid_com		stack

> Allows picks to be weighted in the stacking process based on their quality assigned by the picker. For a pick with a given quality (0 = most reliable, 4 = least reliable), add increment to the count in the cells which meet the stacking criteria. This command is included so that poor quality picks can still contribute to a stack, but with less impact than better quality picks. The increment values set by grid_wt should be reflected in the mthresh value (set by the "thresh" command) used to declare new events (mthresh should be greater than three times the largest grid_wt increment specified). If no "grid_wt" command is issued, only 0-quality picks will be stacked, with an increment of 1. If at least one "grid_wt" command is issued, a pick whose quality was not specified by grid_wt will not used in the stack.

>     Default:  stack only quality=0 		Calnet:  grid_wt 0 4
>               using increment=1			 grid_wt 1 3
>     					         grid_wt 2 2
>     					         grid_wt 3 1

    grid_wt_instid quality increment instid            grid_com                stack

> Allows picks to be weighted in the stacking process based not only on the quality assigned by the picker, but also by the installation id that produced them. For a pick with a given quality (0 = most reliable, 4 = least reliable) from a given instid (character string found in earthworm_global.d), add increment to the count in the cells which meet the stacking criteria. This command is included so that picks from one installation can be weighted differently in a stack than picks from another installation and should only be used by networks that are exchanging pick information. The increment values set by grid_wt_instid and grid_wt should be reflected in the mthresh value (set by the "thresh" command) used to declare new events (mthresh should be greater than three times the largest increment specified). If no "grid_wt_instid" or "grid_wt" command is issued, all 0-quality picks will be stacked, with an increment of 1. If at least one "grid_wt_instid" or "grid_wt" command is issued, a pick whose quality and/or instid was not specified will not used in the stack. grid_wt_instid commands can be used in combination with grid_wt commands; a "grid_wt" command is equivalent to a "grid_wt_instid" command with instid set to INST_WILDCARD.

>     Default:  stack only quality=0         Example:  grid_wt        0 4
>               from any installation                  grid_wt        1 3
>               using increment=1                      grid_wt_instid 2 2 INST_MENLO
>                                                      grid_wt_instid 2 0 INST_CIT

    hypcode	value				bind_com	 	output

> Sets a value to specify how much information should be included in binder_ew's log file after each event relocation. Possible values (0-7) and the corresponding output are a sum of:

> > 0 no output from locator (default)
> > 1 include summary location for each iteration
> > 2 include final phase description for each associated pick
> > 4 include final rms and dmin

> Generally, this parameter should only be included during testing and tuning, since significant increases in the size of the log file and a corresponding decrease in associator efficiency is incurred when it is present and non-zero.

>     Default:  hypcode 0

    lay depth velocity			t_com			model

> Defines the layered velocity structure to be used for calculating travel times. depth is the distance (km) to the top of the layer, and velocity is the seismic P-wave velocity (km/sec) within that layer. No default velocity structure is defined; therefore, the user must always supply one in the control file. Up to 20 layers can be specified, and they should be listed in order of increasing depth.

>     Default:  none				Calnet:  lay   0.0  4.0
>     						 lay   3.5  5.9
>     						 lay  15.0  6.85
>      						 lay  25.0  7.85

    locate_eq npick interval		bind_com		location

> Allows intermittent relocations of an event; an earthquake with more than npick picks will relocate with every additional interval picks associated. This increases binder_ew's efficiency by skipping cpu- intensive relocations of stable events. Up to 10 "locate_eq" commands can be supplied (in order of increasing npick values) to set multiple npick-break-points and location intervals. An event with fewer picks than the smallest npick value will locate after each additional pick is associated.

>     Default: locate after every pick	Calnet:  locate_eq  25   2
>     						 locate_eq  50   4
>     						 locate_eq  75   8
>     						 locate_eq 100  16

    LogFile switch				bndr_config		output

> Sets the on-off switch for writing a log file to disk. If switch is 0, no log file will be written. If switch is 1, binder_ew will write a daily log file(s) called binder_ewxx.log_yymmdd where xx is binder_ew's module id (set with "MyModuleId" command) and yymmdd is the current UTC date (ex: 960123) on the system clock. The file(s) will be written in the EW_LOG directory (environment variable). The amount of information written to the file(s) can also be controlled with the "log_stack" and "hypcode" commands.

>     Default:  none

    log_accepted				assess_com		output

> Tells the pick-assessing function (see "assess_pk" command) to log detailed information for all accepted picks, in addition to info about rejected picks. If this command is ommitted, only information about picks rejected as glitches or outliers will be written to the log file.

>     Default:  don't log accepted picks

    log_stack				grid_com		output

> Tells the program to print a graphical representation of the stack to the log file each time a new hypocenter is declared. Each grid cell in the depth layer containing the hypocenter is represented by a value (0-9,a-z) denoting the number of "hits" in that cell. The trial hypocenter is found by averaging the positions of all the cells which have the maximum number of hits.

>     Default:  don't log the stack

    MaxDeltaRms factor			hyp_com			location

> Sets a factor in the test for divergence of an event's average weighted residual (rms). Solution diverges if rms > previous rms * factor.

>     Default:  MaxDeltaRms 1.01		Calnet:  MaxDeltaRms 1.0001

    MaxIter num				hyp_com			location

> Sets the maximum number of iterations to perform on each relocation.

>     Default:  MaxIter 4			Calnet:  MaxIter 4

    maxpix maxpix				hyp_com			location

> Defines the maximum size of the problem that can be accommodated by the location algorithm. Sufficient space is allocated to allow the location of an event with maxpix picks. The reason for providing this command is so that space need only be allocated once, preventing considerable overhead in the location process.

>     Default:  maxpix 256			Calnet:  maxpix 256

    maxsite nsite				site_com		model

> Allocates memory to store nsite station locations in the site table.

>     Default:  maxsite 1000			Calnet:  maxsite 1000

    MaxStep xystep zstep			hyp_com			location

> Sets maximum limits (km) on the horizontal (xystep) and vertical (zstep) distance a hypocenter can move in each iteration. If either value is exceeded, all 4 dimensions (x, y, z and time) of the step- vector are equally damped, preserving the direction of the vector, such that each dimension is within its limit.

>     Default:  MaxStep 10.0 2.0		Calnet:  MaxStep 25.0  5.0

    maxtrial ntrial				assess_com		pick assess

> Restricts the pick-assessing process to a maximum of ntrial resamplings. Given n picks sampled 4 at a time, the total number of unique combinations is n!/(4!*(n-4)!). If this number is less than ntrial, all possible combinations will be considered, with no duplication. If the total is greater than ntrial, then ntrial random samples of 4 picks will be considered, and duplication is possible.

>     Default:  maxtrial 500			Calnet:  maxtrial 500

    maxwt wt				assess_com		pick assess

> Defines the maximum pick quality wt to consider in the resampling pick-assessing process (see "assess_pk" command). wt must be a character from 0 thru 4. Picks with qualities higher than wt (poorer quality) may be rejected as glitches, but will not be used in resampling to find outliers.

>     Default:  maxwt 3			Calnet:  maxwt 3

    MinXYZstep minstep			hyp_com			location

> Defines the step length (km) at which to stop iterating. If the x-y-z step is less than minstep km, the hypocenter is considered stable and no more iterations are done on this call to hyp_l1.

>     Default:  MinXYZstep 0.1		Calnet:  MinXYZstep 0.1

    MyModuleId mod_id			bndr_config		Earthworm setup

> Sets the module id for labeling all outgoing messages. mod_id is a character string (valid strings are listed in earthworm.d) that relates (in earthworm.d) to a unique single-byte number.

>     Default:  none				Calnet:  MyModuleId MOD_BINDER_EW

    next_id quakeid				bind_com		stack

> Defines the sequence number (quakeid+1) to assign to the next stacked event. Each time an event is created, binder_ew updates a file called "quake_id.d" which contains next available sequence number in the "next_id" command. To ensure sequential, non-duplicated event id's between runs, the parameter file "binder_ew.d" must contain the command "@quake_id.d". If this command is omitted, event sequence numbers will be issued beginning at 1 each time binder_ew is restarted.

>     Default:  next_id 1 			Calnet:  @quake_id.d

    ph phase weight				bind_com		location

> Allows for differential weighting and exclusion of various associated phases in the event location process. The weighting is based on the phase assigned to the pick by the associator.

> > phase can be any of P, S, Pn, Sn, Pg, or Sg
> > weight can be a number between 0.0 and 1.0, inclusive

> If no "ph" commands are supplied, all phases receive a phase-weight of 1.0. If at least one "ph" command is supplied, other phases that have not been listed by "ph" are weighted 0.0. The overall weight of a pick in the location is the product of its phase-weight and quality- weight ("wt" command) divided by the taper value ("taper" command) at the appropriate distance.

>     Default:  all phases/1.0 weight		Calnet:  ph P  1.0
>     						 ph Pn 0.5
>     						 ph Pg 0.5

    psratio value				t_com			model

> Sets the value of the P/S seismic velocity ratio.

>     Default:  psratio  1.72			Calnet:	 psratio  1.72

    r_max rmax				bind_com		location

> Sets the maximum epicentral distance (km) for weighting picks in the location process. Picks from stations at distances greater than rmax km are not weighted.

>     Default:  r_max 150.0			Calnet:  r_max 400.0

    rAvg_Factor factor			bind_com		association

> Sets a factor (scalar) which controls the distance cutoff for associating picks with a given event. If a pick is from a station at an epicentral distance greater than factor*(average epicentral distance of all associated picks), binder_ew will not attempt to assocate that pick with that event.

>     Default:  rAvg_Factor 10.0		Calnet:  rAvg_Factor  7.0

    ray z r					t_com			output

> Prints the travel time from an event at z km depth to a station on the surface at an epicentral distance of r km. This command is used mostly for testing, but might be of some interest in checking travel time calculations or plotting travel time curves.

    raytst z rmax rdel			t_com			output

> Prints out something dealing with the velocity model and travel times.

    region z rmax rdel			t_com			output

> Prints out the travel times of all possible phases at series of points on the surface from an earthquake at z km depth. Those surface points are at epicentral distances from rdel km to rmax km and are spaced rdel km apart. This command, mostly for testing, is useful for plotting travel-time curves.

    residual_cut median mad			assess_com		pick assess

> Sets cutoff thresholds (in seconds) for travel-time residuals in the pick-assessing process. Given a group of picks, up to ntrial (see "maxtrial" command) hypocenters are determined from various combinations of four picks. For each pick, the travel-time residual is calculated with respect to each hypocenter using a uniform-velocity halfspace. If the absolute value of the median of those residuals is greater than median sec, the pick is rejected as an outlier. And if the median of the absolute deviations from the median residual is greater than mad sec, the pick is also rejected as an outlier.

>     Default:  residual_cut 3.0 10.0		Calnet:  residual_cut 3.0 10.0

    RingName ring				bndr_config		Earthworm setup

> Tells binder_ew which shared memory region to use for input and output. ring is a character string (valid strings are listed in earthworm.d) that relates (in earthworm.d) to a unique number for the key to the shared memory region.

>     Default:  none				Calnet:  RingName PICK_RING

    rmscut value				bind_com		location

> Sets a maximum value (seconds) for the average absolute residual (rms) for a successful location. If this value is exceeded as a result of culling, scavenging, or associating a new phase, the event is marked as destroyed and all of its phases are deassigned.

>     Default:  rmscut 1.0 			Calnet:  rmscut 1.0

    rmsgrid value 				grid_com		stack

> No longer used.

    rstack rstack				grid_com		stack

> Defines the distance (km) over which phases are allowed to interact with other phases during the stacking analysis. rstack defines the dimensions of the stacking travel-time template, whose cell size is defined by "dspace" (an rstack of 100 and a dspace of 10 would yield a 10 x 10 travel time template). Phases from stations that are more than 2*rstack km apart will not stack together other because their stacking templates will not overlap.

>     Default:  rstack  100.0			Calnet:  rstack  100.0

    site name latitude longitude		site_com		model

> Enters a station location into the station site table, where name is the station code used by the picker, and latitude and longitude are expressed in decimal degrees (positive to the north and east). Use either multiple "site" commands or one "site_file" command to load the station list into binder_ew.

    site_file filename			site_com		model

> Enters site codes and station locations into the site table by reading a HYPOINVERSE format station file called filename. In this file, stations are described by a 5-letter site name, a 2-letter network code and a 3-letter component code. The picker must also be using this station-naming convention. The format of the file is described under "HYPOINVERSE STATION FILE FOR FULL 12-LETTER (S-N-C-L) CHANNEL NAMES". Use either one "site_file" command or multiple "site" commands to load the station list into binder_ew.

    stack mstack				grid_com		stack

> Determines how many previously received picks are to be considered in the stacking process. A value of 50 to 100 seems appropriate, although if the scatter in reporting delays is large, a larger value of mstack may be required.

>     Default:  stack 20			Calnet:  stack 50

    t_dif tmin tmax				bind_com		associaton

> Defines a time range (seconds) around an event origin-time (origin-time minus tmin to origin-time plus tmax). If a pick-time falls outside of this time range for a given event, binder_ew will not attempt to associate that pick with that event.

>     Default:  t_dif -1.0 120.0  		Calnet:  t_dif -3.0 120.0

    taper r resmax				bind_com		association

> Defines a distance-dependent tolerance for associating, culling, or scavenging a phase, where r is the distance (km) and resmax is the maximum allowed residual (seconds). Multiple taper commands (up to 100) can be issued, in order of increasing r, to define the tolerance function. Between the distances specified, the value of the cutoff residual changes linearly between corresponding resmax values. For distances less than the lowest value specified, the cutoff residual is constant at the resmax value for the smallest distance; for distances exceeding the maximum specified, the cutoff is constant at the resmax value set for the maximum distance. If no "taper" commands are supplied, the cutoff residual is a constant 1.0 sec for all distances.

>     Default:  constant 1.0 sec		Calnet:  taper   0.0   1.0
>     						 taper  50.0   1.0
>     						 taper  200.0  2.5
>     						 taper  400.0  4.5

    taper_OT const1 const2			bind_com		association

> Sets constants for two additional terms to be added to the residual- tolerance function (described for "taper" command). These 2 terms widen the residual-tolerance for events with greater location uncertainty. The first added term (multiplied by const1) depends on the event rms and the number of picks associated with the event. The second additional term is: const2 * log10(distance of closest station) To eliminate the event origin-time uncertainty terms, use the command: taper_OT 0.0 0.0

>     Default:  taper_OT 2.0 2.0		Calnet:  taper_OT 2.0 1.0

    thresh mthresh				grid_com		stack

> Sets the cell-count above which to consider declaring an earthquake from a stack. A completed stack is examined to prepare a list of cells that share the maximum count value and the same minimum distance to the initiating phase. The associator declares a new hypocenter from the stack only if the maximum count value is greater than mthresh and the number of cells in the list is less than nfocus (see "focus" command). The trial hypocenter for the declared event is calculated by averaging the center positions of all the cells in the maximum-count list. mthresh should be greater than 3 times the maximum increment specified by "grid_wt" commands to ensure that at least 4 phases contribute to declaration of a new earthquake.

>     Default:  thresh 6			Calnet:	 thresh 14

    tstack tstack				grid_com		stack

> Defines how close (in seconds) the back-projection of one phase must lie with respect to the back-projection of another phase for the two phases to be considered coherent (ie, from the same source). The value of tstack should reflect the degree of crustal heterogeneity as shown in the range of station delays. As a first approximation, tstack should be at least the number of seconds it takes for a P-wave to cross a grid cell of dspace km.

>     Default:  tstack 0.5			Calnet:  tstack  0.65

    v_halfspace vel				assess_com		pick assess

> Sets the P-wave velocity vel in km/sec of the halfspace used in the pick-assessing process to locate events by the Ingelada method and to calculate travel-times residuals (see "assess_pk" command).

>     Default:  v_halfspace 5.0		Calnet:  v_halfspace 5.0

    wt quality weight			bind_com		location

> Controls the weight of a pick in the event location process based on the quality assigned to the pick by the picker. Picks with a quality of 0 are the most reliable, those with quality 4 are least reliable.

> > quality is any of the values 0, 1, 2, 3, or 4
> > weight is a number between 0.0 and 1.0, inclusive.

> If no "wt" commands are supplied, all picks receive a quality-weight of 1.0. If at least one "wt" command is supplied, other qualites that have not been listed by "wt" are weighted 0.0. The overall weight of a pick in the location is the product of its phase-weight (see "ph" command) and quality-weight divided by the taper value (see "taper" command) at the appropriate distance.

>     Default:  all qualities/1.0 weight	Calnet:  wt 0 1.0
>     						 wt 1 0.5
>     						 wt 2 0.25
>     						 wt 3 0.125

    zrange zmin zmax			hyp_com			location

> Defines the valid range (km) for computed hypocentral depth. The range specified by zmin and zmax must span the depth range set in the "grdz" command; otherwise, events may stack outside of the zrange limit and this could cause locator logic errors. If during the iteration process, the depth falls outside of the zmin-zmax range, a fixed-depth solution is calculated starting at the previous iteration's hypocenter. This feature is useful in controlling locations from network "glitches" where all picks are concurrent and the apparent high phase velocity would try to locate the quake at the center of the Earth.

>     Default:  zrange 2.0 20.0		Calnet:  zrange 1.0 30.0

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