Gravity Map of the Whole EarthBy Mark Simons

Gravity anomalies Coloured freeair gravity anom aly map of the Earth centred on the Atlantic Ocean These anomalies are the differences between the theoretical value for the gravity at the sur face the measured value The colours range from purple low gravity through blue green normal yellow red to white high The anomalies are only a tiny fraction of the gravitational field strength but they can provide information on the Earths internal structure The gravity low in Hudson Bay Canada upper left occurs partly because the areas rocks are recovering from being compressed during the last ice age