Canada - Grid Spacing: 2km - Gravity - Free Air

The Canadian Gravity Anomaly Data Base consists of approximately 660 000 gravity observations, including 165 000 on land, acquired between 1944 and the present. The data spacing ranges from less than 1 km to over 20 km, with an average spacing between 5 and 10 km. All measurements were reduced to the IGSN71 datum. Theoretical gravity values were calculated from the Geodetic Reference System 1967 (GRS67) gravity formula. Bouguer anomalies were calculated using a vertical gravity gradient of 0.3086 mGal·m-1 and a crustal density of 2 670 kg·m-3.