The geoid (/ ˈ dʒ iː. ɔɪ d / JEE-oyd) is the shape that the ocean surface would take under the influence of the gravity of Earth, including gravitational attraction and Earth's rotation, if other influences such as winds and tides were absent.

A geoid is the irregular-shaped “ball” that scientists use to more accurately calculate depths of earthquakes, or any other deep object beneath the earth’s surface. Currently, we use the “WGS84” version (World Geodetic System of 1984).

Geoid, model of Earth’s size and shape that coincides with mean sea level over the oceans and continues in continental areas as an imaginary sea-level surface. It is everywhere perpendicular to the pull of gravity and approximates the shape of a regular oblate spheroid (i.e., a …

The geoid is a model of global mean sea level that is used to measure precise surface elevations. A depiction of the United States geoid. Areas in yellow and orange have a slightly stronger gravity field as a result of the Rocky Mountains.

Jan 30, 2001 · geoid: The equipotential surface of the Earth’s gravity field which best fits, in a least squares sense, global mean sea level. Even though we adopt a definition, that does not mean we are perfect in the realization of that definition.

This irregular shape is called "the geoid," a surface which defines zero elevation. Using complex math and gravity readings on land, surveyors extend this imaginary line through the continents. This model is used to measure surface elevations with a high degree of accuracy.

The particular equipotential surface that coincides over the oceans with unperturbed mean sea level constitutes the geoid. Under the continents the geoid is not directly accessible but is rather the surface to which water would rise if narrow canals were cut

The geoid is the shape that the surface of the oceans would take under the influence of Earth's gravitation and rotation alone, in the absence of other influences such as winds and tides. It was defined by Gauss, in 1828. [1] . It is often described as the true physical shape of the Earth. [2] .

Apr 11, 2023 · Geoid is defined as an equipotential surface of the Earth’s gravity field that coincides with the mean sea level. It is an imaginary surface that closely approximates the shape of the Earth, taking into account the irregularities in the distribution of mass within the Earth.

The geoid measures mean sea level and gravity. The GRACE and GOCE satellites are providing the most accurate measurements of the geoid to this date.