GPS TIME SERIES SCHEMA - SUPPORTED FORMATS

GPS GML Schema

Information about supported GPS data formats can be found in
http://www.scign.org

Current GML Seismicity Schema supports 3 formats
JPL      Time series for all sites
SOPAC Time series for all sites
USGS   Rapid analysis results

Format Specifications - Info about the columns of each catalog

 JPL TIME SERIES

Time series are given as three ascii files SITE.lat, SITE.lon, and
SITE.rad containing the time in years, estimate in cm, sigma in cm, site,
component, and date. Stacov files contain X, Y, Z estimates in m, sigmas in m, 
and correlations. 
Col  Comment
1:   time      [in years] 
2:   estimate  [in cm] 
3:   sigma     [in cm] 
4:   site 
5:   component 
6:   date

SAMPLE

[File 70DM.lat]
time in years  estimate in cm          sigma in cm,           site  component   date
2001.6427      0.480731548657252E-01   0.190967658896982E+00  7ODM  LAT         01AUG23   
2001.6455     -0.411582988507547E-02   0.115527109363862E+00  7ODM  LAT         01AUG24   
2001.6482      0.618315231694152E-01   0.120494136411178E+00  7ODM  LAT         01AUG25   

TABLE2.TXT

There is metadata about the GPS sites, corresponding to the file names in ./point and ./filtered, in the files ./table.txt and ./table2.txt. 
It looks like the distinction is that table.txt contains cartesian coordinates for each station, while table2.txt has this expressed in latitude
and longitude (in a particular reference frame system). (Jay W. Parker)

> 2) Are columns of .lat, .lon,.rad relative postion with respect  to 
> table2.txt positions in cm, then uncertainty (1-sigma uncertainty?) also 
> in cm?

Yes, the columns of .lat, .lon, and .rad are relative to the position
in table2.txt which has an epoch of July 1, 2003.  The positions and
velocities in table2.txt were estimated by fitting all the data for a
particular site.

> 
> 3) so table2.txt has height in mm above ellipsoid (essentially like sea 
> level ?) and errors (1 sigma?) are in mm for all types. What are these 
> estimates and errors based on? (is this the average postition over the 
> data we collected at some point, with "error" based on the error of each 
> day's position over root-N?)

Yes, the height estimates are given relative to the WGS84 reference
ellipsoid.  The dailt formal errors have been multiplied by 3 so that
chi^2/dof is roughly 1 for each site when doing a linear fit.
 
#The reference frame is ITRF2000. The epoch is July 1, 2003.
#The reference ellipsoid for latitude, longitude, and height is WGS84.
#Latitude and longitude are given in degrees. Height is given in mm.
#Latitude, longitude, and height errors are given in mm.
#Velocities and their errors are given in mm/yr.

                    LAT            LON         HEIGHT
AGMT POS   34.594281903 -116.429378066     1337851.10     0.20     0.35     0.79
AGMT VEL           0.13         -18.86           4.78     0.10     0.17     0.40
AIS1 POS   55.069072287 -131.599535423       32253.80     0.84     1.09     2.58
AIS1 VEL         -12.40         -14.59           1.52     0.31     0.40     0.94
AJAC POS   41.927457067    8.762614171       98769.90     0.34     0.52     1.17
ALBH POS   48.389781214 -123.487470380       31762.50     0.13     0.19     0.44
ALBH VEL          -9.32          -8.27           0.80     0.02     0.04     0.09

TABLE.TXT

#The reference frame is ITRF2000.  The epoch is July 1, 2003.
#Positions given in mm.  Velocities given in mm/yr.

                      X              Y              Z
AGMT POS -2339956268.10 -4707748827.06  3601666104.12     0.45     0.62     0.45
AGMT VEL         -18.61           4.94           2.82     0.22     0.31     0.22
AIS1 POS -2430153915.65 -2737192932.49  5205816635.55     1.38     1.47     2.12
AIS1 VEL         -18.24           1.43          -5.85     0.51     0.53     0.77
AJAC POS  4696989462.34   723994439.61  4239678509.31     0.93     0.53     0.78
 

 SOPAC TIME SERIES

Columns
decimal year, 
year, 
day-of-year, 
[x,y,z OR north,east,up (m)],  
[x,y,z sigma OR n,e,u sigma]

SAMPLE

      decimal year     year  day-of-year  [x,y,z OR north,east,up (m)]  [x,y,z sigma OR n,e,u sigma]
[flt.neu]2001.3055     2001  111          -0.0008  0.0246 -0.0085         0.0082  0.0082  0.0088 
[unf.neu]2001.3055     2001  111           0.0007  0.0247 -0.0158         0.0082  0.0082  0.0088
[raw.neu]2001.3055     2001  111           0.0007  0.0247 -0.0158         0.0082  0.0082  0.0088
[raw.xyz]2001.3055     2001  111          -2407750.8841 -4706536.7243    3557571.3937  0.0077  0.0097  0.0076

USGS TIME SERIES

Columns
Decimal_Year 
Time Stamp
North_(mm)
North_error_(mm) 
East_(mm) 
East_error_(mm) 
Up_(mm) 
Up_error_(mm) 
Double_Diff_Obs 
Phase 
Bias_Flag1 
Bias_Flag2 
Troposphere 
North_East_rho
North_Up_rho 
East_Up_rho 
X 
X_error 
Y 
Y_error 
Z 
Z_error

SAMPLE

# NOTE: The decimal year values are calculated for each datapoint 
#       by dividing the decimal day by 365 (or 366 if it's a leap 
#       year) and adding this to the year.  Zero begins at the 
#       beginning of the day.  Positions are generally taken at 
#       noon each day, although newer datapoints may be subdaily.
# Site  Code: AGMT
# 
Decimal_Year            Time Stamp	             North_(mm)	       North_error_(mm)	              East_(mm)	        East_error_(mm)	                Up_(mm)	          Up_error_(mm)	        Double_Diff_Obs	                  Phase	             Bias_Flag1	             Bias_Flag2	            Troposphere	         North_East_rho	           North_Up_rho	            East_Up_rho	                      X	                X_error	                      Y	                Y_error	                      Z	                Z_error
1999.970318      1999-355:03:59:00	        3851017839.9000	                 3.0000	       22319997874.5000	                 3.7000	           1337846.0000	                17.6000	                       	                       	                       	                       	                       	                       	                       	                       	       -2339956199.2000	                 7.5000	       -4707748860.1000	                13.2000	        3601666097.0000	                10.0000
1999.970320      1999-355:04:00:00	                       	                       	                       	                       	                       	                       	                       	              9000.0000	                       	                       	                       	                       	                       	                       	                       	                       	                       	                       	                       	                       
1999.973057      1999-356:03:59:00	        3851017841.8000	                 1.6000	       22319997874.2000	                 2.9000	           1337834.5000	                 9.5000	                       	                       	                       	                       	                       	                       	                       	                       	       -2339956194.8000	                 4.5000	       -4707748850.5000	                 7.1000	        3601666092.0000	                 5.5000
1999.973059      1999-356:04:00:00	                       	                       	                       	                       	                       	                       	                       	              3700.0000