CHIL Site Information Form
     International GPS Service for Geodynamics


0.   Form

     Prepared by (full name)  : Ken Hudnut and John Galetzka
     Date Prepared            : 23-DEC-1997
     Report Type              : UPDATE
     Prepared Using           :


1.   Site Identification of the GPS Monument

     Site Name                : Chilao Flats
     Four Character ID        : CHIL
     Monument Inscription     : None
     IERS DOMES Number        : 40484M001
     CDP Number               : Not assigned
     Date Installed           : 02-SEP-1994 hh:mm UT
     Geologic Characteristic  : BEDROCK
       Bedrock Type           : IGNEOUS
       Bedrock Condition      : SLIGHTLY WEATHERED, JOINTED
       Fracture Spacing       : over 200 cm
       Notes                  : (multiple lines)
     Additional Information   : 3/4" diameter vertical stainless steel rod with
                              : removable brass adaptor. Vertical datum is
                              : filed notch on vertical rod. Granitic outcrop
                              : foundation, 4 stainless steel rods epoxied in
                              : granite- one vertical, three oblique, welded
                              : above surface.
                              : SCIGN - Southern California Integrated GPS
                              : Network


2.   Site Location Information

     City or Town             : San Gabriel Mountains
     State or Province        : California
     Country                  : USA
     Tectonic Plate           : Pacific-North American plate boundary
     Approximate Position
       X coordinate (m)       : -2478002.976
       Y coordinate (m)       : -4655349.418
       Z coordinate (m)       :  3577932.224
       Latitude (deg)         :   34.3334
       Longitude (deg)        : -118.0260
       Elevation (m)          : 1568.6175
     Additional Information   : ITRF92 coordinates. Epoch 1994.75
                              : Los Angeles County
                              : (multiple lines)


3.   GPS Receiver Information

3.1  Receiver Type            : ASHTECH ZX-II3 (Z12) Model 700570-6B
     Serial Number            : 03460 (Loaner # 2)
     Firmware Version         : NAV 1D00, CHN 1C01
     Date Installed           : 02-SEP-1994 hh:mm UT
     Date Removed             : (dd-MMM-yyyy hh:mm UT)
     Additional Information   : First measurements

3.2  Receiver Type            : ASHTECH LP Z-XII (Z12) Model 700845-1(1)
     Serial Number            : 04538 (USGS Property #G-615683)
     Firmware Version         : NAV 1E24, CHN 1C70
     Date Installed           : 06-APR-1995 hh:mm UT
     Date Removed             : (dd-MMM-yyyy hh:mm UT)
     Additional Information   : exchanged unit Loaner #2 for new USGS LP unit

3.3  Receiver Type            : ASHTECH LP Z-XII (Z12) Model 700845-6(1)
     Serial Number            : 04356, USGS Property #G-615686 ??)
     Firmware Version         : NAV 1E24, CHN 1C70
     Date Installed           : 30-MAY-1995 hh:mm UT
     Date Removed             : (dd-MMM-yyyy hh:mm UT)
     Additional Information   : receiver RAM upgrade - antenna exchanged from
                              : LGP to DM type

3.4  Receiver Type            : ASHTECH LP Z-XII (Z12) Model 700845-6(1)
     Serial Number            : 04356, USGS Property #G-615686 ??)
     Firmware Version         : NAV 1E95, 1D01
     Date Installed           : 25-SEP-1996 hh:mm UT
     Date Removed             : (dd-MMM-yyyy hh:mm UT)
     Additional Information   : Firmware upgrade

3.5  Receiver Type            : ASHTECH LP Z-12 Model 700845-10(F)
     Serial Number            : LP03012
     Firmware Version         : NAV 1F50, 1D02
     Date Installed           : 20-NOV-1997 hh:mm UT
     Date Removed             : (dd-MMM-yyyy hh:mm UT)
     Additional Information   : New reciever with updated firmware installed to
                              : accommodate new met package.

3.x  Receiver Type            :
     Serial Number            :
     Firmware Version         :
     Date Installed           : (dd-MMM-yyyy hh:mm UT)
     Date Removed             : (dd-MMM-yyyy hh:mm UT)
     Additional Information   : (multiple lines)


4.   GPS Antenna Information

4.1  Antenna Type             : ASHTECH L1/L2 P Model 700718-B (Lg Ground Plane)
     Serial Number            : 10334
     Antenna Height (m)       : 0.6440
     Antenna Reference Point  : BPA
     Degree Offset from North :
     Antenna Radome Type      :
     Date Installed           : 02-SEP-1994 hh:mm UT
     Date Removed             : (dd-MMM-yyyy hh:mm UT)
     Additional Information   : In field, measured 66.0 cm to wide part of
                              : pre-amp and corrected by subtracting 1.60 cm.
                              : SOPAC's older logs for this site stated 0.0644 m
                              : which was off by a factor of 10x (unit error).

4.2  Antenna Type             : ASHTECH L1/L2 P Model 700718-B (Lg Ground Plane)
     Serial Number            : 10859
     Antenna Height (m)       : 0.6440
     Antenna Reference Point  : BPA
     Degree Offset from North :
     Antenna Radome Type      :
     Date Installed           : 06-APR-1995 hh:mm UT
     Date Removed             : (dd-MMM-yyyy hh:mm UT)
     Additional Information   : In field, measured both to base of narrow part
                              : (threaded base) which is 0.6440 m, and to base
                              : of wide part 0.660 m (a difference of 1.60 cm)

4.3  Antenna Type             : ASHTECH Model 700936-A (Metal Choke Ring)
     Serial Number            : 11497
     Antenna Height (m)       : 0.6440 (see above NOTE)
     Antenna Reference Point  : ARP/BPA
     Degree Offset from North :
     Antenna Radome Type      :
     Date Installed           : 30-MAY-1995 hh:mm UT
     Date Removed             : (dd-MMM-yyyy hh:mm UT)
     Additional Information   : Same filed notch used as vertical datum. No
                              : field log was written when DM antenna was
                              : emplaced.

4.4  Antenna Type             : ASHTECH Model 700936-A (Metal Choke Ring)
     Serial Number            : 11497
     Antenna Height (m)       : 0.6440
     Antenna Reference Point  : ARP/BPA
     Degree Offset from North :
     Antenna Radome Type      :
     Date Installed           : 25-SEP-1997 hh:mm UT
     Date Removed             : (dd-MMM-yyyy hh:mm UT)
     Additional Information   : No changes to antenna at this time.

4.5  Antenna Type             : ASHTECH Model 700936-A (Metal Choke Ring)
     Serial Number            : 11497
     Antenna Height (m)       : 0.6440
     Antenna Reference Point  : ARP/BPA
     Degree Offset from North :
     Antenna Radome Type      :
     Date Installed           : 25-SEP-1997 hh:mm UT
     Date Removed             : (dd-MMM-yyyy hh:mm UT)
     Additional Information   : No changes to antenna at this time.

4.x  Antenna Type             :
     Serial Number            :
     Antenna Height (m)       : (m)
     Antenna Reference Point  : (ARP/BCR/BPA)
     Degree Offset from North :
     Antenna Radome Type      :
     Date Installed           : (dd-MMM-yyyy hh:mm UT)
     Date Removed             : (dd-MMM-yyyy hh:mm UT)
     Additional Information   : (multiple lines)


5.   Local Site Ties

5.x  Monument Name            :
     Site Ref CDP Number      : (XXXX)
     Site Ref Domes Number    : (XXXXXXXXX)
     Differential Components from GPS Mark to Site Reference (ITRS)
       dx (m)                 : (m)
       dy (m)                 : (m)
       dz (m)                 : (m)
     Accuracy (mm)            : (mm)
     Date Measured            : (dd-MMM-yyyy hh:mm UT)
     Additional Information   : (multiple lines)


6.   Frequency Standard

6.1  Standard Type            : INTERNAL
       Frequency              :
       Effective Dates        : 02-SEP-1994 - dd-MMM-yyyy
       Notes                  : (multiple lines)

6.x  Standard Type            : (H-MASER/CESIUM/QUARTZ/INTERNAL/RUBIDIUM)
       Frequency              :
       Effective Dates        : (dd-MMM-yyyy - dd-MMM-yyyy)
       Notes                  : (multiple lines)


7.   Collocation Information

7.x  Instrumentation Type     : (DORIS/GLONASS/PRARE/SLR/VLBI)
       Status                 : (PERMANENT/MOBILE)
       Effective Dates        : (dd-MMM-yyyy - dd-MMM-yyyy)
       Notes                  : (multiple lines)


8.   Meteorological Instrumentation

8.1  Humidity Sensor Model    : MET 3
       Manufacturer           : Paroscientific
       Data Frequency         : 600 seconds
       Accuracy (% rel h)     : +/- 2% @ 25C
       Effective Dates        : 20-NOV-1997 - present
       Notes                  : SN 67619

8.2  Pressure Sensor Model    : MET 3
       Manufacturer           : Paroscientific
       Data Frequency         : 600 seconds
       Accuracy (mbar)        : NA
       Height Diff to GPS (m) : ~ -0.5m
       Effective Dates        : 20-NOV-1997 - present
       Notes                  : SN 67621

8.3  Temperature Sensor Model : MET 3
       Manufacturer           : Paroscientific
       Data Frequency         : 600 seconds
       Accuracy (deg C)       : <= .5
       Effective Dates        : 20-NOV-1997 - present
       Notes                  : SN 67619

8.4  Water Vapor Radiometer   :
       Manufacturer           :
       Distance to GPS (m)    : (m)
       Elev Diff to GPS (m)   : (m)
       Effective Dates        : (dd-MMM-yyyy - dd-MMM-yyyy)
       Notes                  : (multiple lines)

8.5  Other Instrumentation    : (multiple lines)


9.   On-Site, Point of Contact Agency Information

     Agency                   : U.S. Geological Survey
     Mailing Address          : 525 South Wilson Ave.
                              : Pasadena, CA 91106
     Primary Contact
       Contact Name           : John Galetzka
       Telephone (primary)    : 818-583-7230
       Telephone (secondary)  :
       Fax                    : 818-583-7827
       E-mail                 : galetzka@gps.caltech.edu
     Secondary Contact
       Contact Name           :
       Telephone (primary)    :
       Telephone (secondary)  :
       Fax                    :
       E-mail                 :
     Additional Information   : (multiple lines)


10.  Responsible Agency (if different from 9.)

     Agency                   : (multiple lines)
     Mailing Address          : (multiple lines)
     Primary Contact
       Contact Name           :
       Telephone (primary)    :
       Telephone (secondary)  :
       Fax                    :
       E-mail                 :
     Secondary Contact
       Contact Name           :
       Telephone (primary)    :
       Telephone (secondary)  :
       Fax                    :
       E-mail                 :
     Additional Information   : (multiple lines)


11.  More Information

     URL for More Information :
     Hardcopy on File
       Site Map               : (Y)
       Site Diagram           : (Y)
       Horizon Mask           : (Y)
       Monument Description   : (Y)
       Site Pictures          : (Y)
     Additional Information   : (multiple lines)
     Antenna Graphics with Dimensions


             ASHTECH: Metal Choke Ring Type
             NOTE: Dimensions and Offsets Presumed to be same as
                   for TURBOROGUE DM-T (tests pending)

                         -----
                     /     +     \                        <-- 0.128  L2
                    |      +      |                       <-- 0.110  L1
  +--------------------------------------------------+    <-- 0.102  TCR
  |                                                  |
  |                                                  |
  |                                                  |
  |                                                  |
+-+--------------------------------------------------+-+  <-- 0.038
+-------------------+-------------+--------------------+  <-- 0.035  BCR
                    |             |
                   =|             |
A
                    +------x------+                       <-- 0.000  ARP
                                                             -0.???
                                                         ARP to vert datum mark
<--                      0.381                       -->

NOTE: LGP removed on approx. May 30, 1995 (exchanged for ASHTECH DM type - see above)


               ASHTECH: GEODETIC L1/L2 P Large Ground Plane

                           ^
                 +-------------------+
+-+--+-+-------+-----------+-----------+--------+-+--+-+   <--  0.064 TGP=L1=L2
+-+--+-+------------+-------------+-------------+-+--+-+   <--  0.??? BGP
                    |-------------|
                    |-------------|
                    +-------------+                        <--  0.660 m
                         |---|                        (NOTE: 1.6 cm difference)
                         +-x-+                             <--  0.644 ARP=BPA
                                                      (NOTE: we use this!)

                  <--    0.080    -->
<--                      0.3474                      -->


   ARP: Antenna Reference Point
   L1 : L1 Phase Center                   L2 : L2 Phase Center
   TCR: Top of Choke ring                 BCR: Bottom of Choke ring
   TGP: Top of Ground Plane               BGP: Bottom of Ground Plane
   TPA: Top of Preamplifier               BPA: Bottom of Preamplifier