In precise gravity surveys of mountainous areas, a sudden and large change in reading values of LaCoste & Romberg gravimeters has frequently been experienced immediately after climbing down from a high altitude. In the course of international gravimetric connections, gravity measurements in mountainous areas were performed by means of several LaCoste & Romberg gravimeters (model G) along a route from Valparaiso on the Pacific coast to Caracoles on the border of Chile-Argentina in Chile. This route was satisfactory for examining the effects of the rapid change of atmospheric pressure on the gravimeter readings. Because both the measuring stations are located at a height difference amounting to more than 3, 000m, and it was of great advantage to the examination that it took only a single day by car to travel to and from both the measuring stations. It was ascertained that relative deviations in reading values for three gravimeters employed were well correlated with the difference of station altitudes. As gravity measurements for the international gravimetric connections were executed just before and immediately after air transportation at measuring stations in airports, the international gravimetric connections provided an opportunity to examine such an effect of air transportation. However, a large deviation of gravity values measured on the route between Valparaiso and Caracoles was not found on any of the other routes of air transportation.
