Gravity
Earth's gravity measured by NASA's GRACE mission Gravity profiling measures the Earth’s gravitational acceleration over an area of interest. The strength of the gravitational field is directly proportional to the density of subsurface materials. Anomalies in the earth’s gravitational field result from lateral variations in the density of subsurface materials. In the past, typically relative measurements of the Earth’s gravity field were generally inefficient; hence gravity surveys are typically more expensive to conduction. Similar to other geophysical instrumentations, recent advancements has allowed this technique to become a more efficient means of exploratory geophysics. New instrumentation advanced include automatic corrections for tide, instrument tilt, temperature, drift, near terrain, noisy sample, and seismic noise filter. Typical applications for the gravity profiling include:
In the past, prior usage of gravity surveying had been concentrated on detecting subsurface caverns using a spring based relative gravimeter manufactured by LaCoste & Romberg.
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