Gravitätsmessungen

Gravitätsmessungen, also known as gravity surveys or gravimetry, are a geophysical method used to measure variations in the Earth's gravitational field. These variations are primarily caused by differences in the density of subsurface materials. Denser rocks exert a stronger gravitational pull than less dense rocks. By carefully measuring the acceleration due to gravity at numerous points on the Earth's surface or in boreholes, scientists can infer the geological structure and composition beneath.

The primary instrument used in gravitätsmessungen is the gravimeter, a highly sensitive device that measures minute changes in gravity. These instruments typically employ a spring system or a vibrating string whose tension or frequency changes in response to gravitational variations. Measurements are usually expressed in milligals (mGal), where one gal is equal to one centimeter per second squared, and a milligal is one-thousandth of that.

Gravitätsmessungen have a wide range of applications. They are crucial in petroleum and mineral exploration to identify potential underground deposits by detecting anomalies in gravity caused by ore bodies or hydrocarbon reservoirs. In geological research, they help map subsurface structures like faults, folds, and salt domes, contributing to our understanding of tectonic processes and basin evolution. Furthermore, gravitätsmessungen are used in geodesy to determine the geoid, the idealized mean sea level surface, and to study Earth's interior, including mantle dynamics and ice sheet thickness variations. Corrections are applied to raw gravimeter readings to account for factors such as elevation, latitude, and the gravitational pull of nearby topography, ensuring accurate interpretations of the subsurface.