3.3.7. glorg.cmd
The glorg command file has the form:
* glorg command file for time series, short-term combinations and velocity solutions
* Set VEL as a globk command-line option for velocity; since these commands follow
* the commands for repeatabilities, they will take precedence when invoked.
* Add choice of plate for final reference frame (e.g. EURA14 for Eurasia defined by
* Altamimi et al.'s (2017) ITRF2014 plate motion model, NOAM08 for North America
* defined by Altamimi et al's (2012) ITRF2008 plate motion model, NA1214 for North
* America defined by Blewitt et al. (2013) using rotated ITRF2014 velocities, etc.
* Last edited by MAF 180519
* << column 1 must be blank if not comment >>
* Parameters to be estimated
pos_org xtran ytran ztran xrot yrot zrot
VEL rate_org xtran ytran ztran xrot yrot zrot
# Optionally, if estimated scale in GLOBK:
SCALE pos_org xtran ytran ztran xrot yrot zrot scale
xSCALE rate_org xtran ytran ztran xrot yrot zrot
# or if translation-only
x pos_org xtran ytran ztran
xVEL rate_org xtran ytran ztran
* Downweight of height relative to horizontal (default is 10 10)
# Heavy downweight if reference frame robust and heights suspect
x cnd_hgt 1000 1000
* Controls for removing sites from the stabilization
# Vary these to make the stabilization more robust or more precise
stab_it 4 0.8 3.0
x stab_it 4 0.5 4.0
* A priori coordinates to define the analysis reference frame
apr_file ~/gg/tables/igb14_comb.apr
ITRF08 apr_file ~/gg/tables/itrf08_comb.apr
# ITRF2014 plate motion model defined by Altamimi et al. (2017)
AMUR14 apr_file ~/gg/tables/igb14_comb_amur08.apr
ANTA14 apr_file ~/gg/tables/igb14_comb_anta.apr
ARAB14 apr_file ~/gg/tables/igb14_comb_arab.apr
AUST14 apr_file ~/gg/tables/igb14_comb_aust.apr
CARB14 apr_file ~/gg/tables/igb14_comb_carb08.apr
EURA14 apr_file ~/gg/tables/igb14_comb_eura.apr
INDI14 apr_file ~/gg/tables/igb14_comb_indi.apr
NAZC14 apr_file ~/gg/tables/igb14_comb_nazc.apr
NOAM14 apr_file ~/gg/tables/igb14_comb_noam.apr
NUBI14 apr_file ~/gg/tables/igb14_comb_nubi.apr
PCFC14 apr_file ~/gg/tables/igb14_comb_pcfc.apr
SOAM14 apr_file ~/gg/tables/igb14_comb_soam.apr
SOMA14 apr_file ~/gg/tables/igb14_comb_soma.apr
SUND14 apr_file ~/gg/tables/igb14_comb_sund08.apr
# North America defined by Blewitt et al. (2013)
NA1214 apr_file ~/gg/tables/igb14_comb_na12.apr
# North America defined by Kreemer et al. (2018)
NA1714 apr_file ~/gg/tables/igb14_comb_na17.apr
# Nubia and Somalia defined by Saria et al. (2013)
NU1314 apr_file ~/gg/tables/igb14_comb_nu13.apr
SO1314 apr_file ~/gg/tables/igb14_comb_so13.apr
# ITRF2008 plate motion model defined by Altamimi et al. (2012)
AMUR08 apr_file ~/gg/tables/itrf08_comb_amur.apr
ANTA08 apr_file ~/gg/tables/itrf08_comb_anta.apr
ARAB08 apr_file ~/gg/tables/itrf08_comb_arab.apr
AUST08 apr_file ~/gg/tables/itrf08_comb_aust.apr
CARB08 apr_file ~/gg/tables/itrf08_comb_carb.apr
EURA08 apr_file ~/gg/tables/itrf08_comb_eura.apr
INDI08 apr_file ~/gg/tables/itrf08_comb_indi.apr
NAZC08 apr_file ~/gg/tables/itrf08_comb_nazc.apr
NOAM08 apr_file ~/gg/tables/itrf08_comb_noam.apr
NUBI08 apr_file ~/gg/tables/itrf08_comb_nubi.apr
PCFC08 apr_file ~/gg/tables/itrf08_comb_pcfc.apr
SOAM08 apr_file ~/gg/tables/itrf08_comb_soam.apr
SOMA08 apr_file ~/gg/tables/itrf08_comb_soma.apr
SUND08 apr_file ~/gg/tables/itrf08_comb_sund.apr
# North America defined by Blewitt et al. (2013)
NA1208 apr_file ~/gg/tables/itrf08_comb_na12.apr
# North America defined by Kreemer et al. (2018)
NA1708 apr_file ~/gg/tables/itrf08_comb_na17.apr
# Nubia and Somalia defined by Saria et al. (2013)
NU1308 apr_file ~/gg/tables/itrf08_comb_nu13.apr
SO1308 apr_file ~/gg/tables/itrf08_comb_so13.apr
# Use a regional stablization if available from a prior solution (comment out the itrf08 file)
x apr_file ../tables/regional.apr
* List of stabilization sites
# This should match the well-determined sites in the apr_file
stab_site clear
x source ~/gg/tables/igb14_hierarchy.stab_site
source ~/gg/tables/igb14_comb.stab_site
xITRF08 source ~/gg/tables/igb08_hierarchy.stab_site
ITRF08 source ~/gg/tables/itrf08.stab_site
# Use a regional stabililization if available from a prior solution
x source ../tables/regional_stab_site
* Estimate rotation (Euler) vectors to be used with sh_org2vel to
* to rotate the solution to a block- or region-specific reference frame
xVEL plate eurasia kosg_2ps onsa_2ps nyal_4ps graz_2ps tlse_2ps kit3_2ps
xVEL plate eurasia vill_3ps mars_3ps cbre
xVEL plate weura kosg_2ps tlse_2ps vill_3ps mars_3ps
xVEL plate aegean milo kyra xris dioa leon mkn2 bodr roml omal koun seva
# Constrain the center-of-mass to the apr-file in plate estimate (comment out for global solutions)
xVEL NOPLATETRAN
* Equate the velocities of co-located sites
VEL eq_dist 1000 ndot
VEL eq_dist 1000 edot
VEL eq_dist 1000 udot
* Equate a few horizontal velocities for sites farther apart
VEL equate trab_gps ndot akto_gps ndot
VEL equate trab_gps edot akto_gps edot
* Unequate velocities that are incompatible
VEL unequate mad2_gps ndot
VEL unequate mad2_gps edot
VEL unequate mad2_gps udot
Frame definition (stabilization or spatial filtering) is accomplished in glorg by specifying a set of sites for which the a priori coordinates are known at the level you expect the frame to be defined (usually 1–2 mm horizontal, 2–5 mm vertical) and the parameters you want to estimate in order to minimize the coordinate adjustments for these sites.
If an apr_file is included in the glorg command file, its coordinates will supersede those used in GAMIT or globk, so it is not necessary to use the same a priori coordinates for all three programs.
For glorg, the only coordinates that matter are those for the stabilization sites.
The pos_org command specifies the parameters to be estimated, either translation only (omit the last three entries) or translation and rotation.
The rules for stab_site are the same as those for use_site in the globk command file.
See Section 5.4 for a more comprehensive discussion of reference frame definition.
The next two entries in the file control the weighting of the quasi-observations (site coordinates) in the stabilization.
For cnd_hgtv the first two values specify (for position and velocity, respectively) the down-weighting of heights relative to horizontal coordinates.
The default is 10, under the assumption that the uncertainties in heights are about three times higher than for the horizontal coordinates;
however, you can increase this ratio if want to define only a horizontal frame or you know that the height estimates are unreliable.
The last two values set limits on the uncertainty in height allowed to have a site included and serve to remove from the stabilization poorly determined sites.
For stab_it the first value is the number of iterations used in the stabilization, the second the amount of reweighting that can take place between iterations, and the third the ratio of residual to uncertainty (sigma) allowed before a site is removed from the stabilization.
You can change the last value to fine-tune the inclusion or exclusion of sites from the frame definition.
These commands are discussed in more detail in the glorg help file and Section 3.2 of the GLOBK Reference Manual.