Natural Resources Canada
Government of Canada
Gravity data
Format description for gravity anomaly point data of Canada

No. Column Field Description
1 X Same as LONGITUDE.
2 Y Same as LATITUDE.
3 LONGITUDE The longitude in decimal degrees. West longitude is negative, east longitude is positive.
4 LATITUDE The latitude in decimal degrees. North latitude is positive, south latitude is negative.
5 PROJECT A project number in the form CCYYNNN where CCYY is the year of observation, and NNN is a unique number in that year.
6 STATION A 6 digit station number
7 YEAR Year of observation in the form CCYY.
8 DDMMYYYY Observation date in the form DDMMYYYY.
9 HHMM Observation time (GMT) in the form HHMM.
10 CAV The accuracy of the coordinates in metres.
11 ELEVATION The elevation in metres above sea level.
12 EAV The accuracy of the elevation in metres.
13 DEPTH The depth of water or thickness of ice in metres.
14 DAV The accuracy of the depth or thickness in metres.
15 DEPTHTYPE The type of observation, as follows :
  1. A depth of water or thickness of ice was present but was not measured.
  2. Observation taken on land.
  3. Observation taken on the surface of an ocean or lake.
  4. Observation taken on the bottom of an ocean or lake.
  5. Observation taken on an ice cap.
  6. Observation taken on an ice-covered ocean or lake.
  7. Observation taken on the surface of the sea in a fiord.
  8. Observation taken on sea ice in a fiord.
  9. Observation taken on the bottom of the sea in a fiord.
16 ADJG The observed value of gravity referred to IGSN71 in milligals.
17 GAV The accuracy of the observed gravity in milligals.
18 TCOR The terrain correction in milligals.
19 TAV The accuracy of the terrain correction.
20 FREEAIR The free air anomaly in milligals (See formulae for Anomaly Computation).
21 FAV The accuracy of the free air anomaly computed using the accuracies of the values used in its computation.
22 BOUGUER The Bouguer anomaly in milligals (See formulae for Anomaly Computation).
23 BAV The accuracy of the Bouguer anomaly computed using the accuracies of the values used in its computation.
24 STATUS The status of the observation, as follows :
  1. Active
  2. Deleted.


References

Anomaly computation formulae