Applied Geophysics – a scientific approach including a series of non-destructive survey methods, based on the precise registration of the physical manifestations of the sub-surface environment. Changing conditions in the sub-surface environment cause deformations of the related part of the registered physical field. The variability of the environment, structural failures, infiltration and increased concentration of natural and anthropogenic factors are the elements affecting the physical manifestation of the prevailing environment.

Gravimetry Magnetic

Based on different densities of building material, the geological structures and elements in the Earth's crust are structurally differentiable. Gravimetric methods are based on registration of changes in effective gravity acceleration; effective gravity acceleration - the resultant force of the planet's gravity reduced by centrifugal force generated by rotation of the planet. The source of the anomalous changes in effective gravity towards their general environment are density inhomogeneity in the Earth's crust. Depending on the size and density of the bodies, their mutual influence and the degree of interaction with the impact of physical surroundings differ; the bodies with greater effective mass eliminate the manifestation of its surroundings more and vice versa. Based on the size of the examined area, the gravimetry is divided into exploration gravimetry and micro-gravimetry.

In 1890 the Hungarian-Austrian physicist, Lorand Eötvös, constructed the first precision equipment (Eötvös torsion balance), registering the effect of the Earth's gravity field. The original purpose of Eötvös torsion balance was the use for the needs of Higher geodesy but after initial testing, in 1898 Eötvös improved and adapted his device for use for geological survey purposes. In 1900, his torsion balances gained the prestigious award „Grand Prix“ at the „World Expo“ in Paris. In 1902 Eötvös improved the registration system into its final form and in the coming period, several successful exploratory campaigns were carried out. Worldwide interest was brought up with a survey conducted by Hugo von Böckh in 1916 on territory which is presently the Slovak Republic in the Gbely area. The use of Eötvös torsion balance helped to map the anticlinal structural trap that holds the hydro-carbons. The survey results were then confirmed by drilling works. This success led to huge interest from mining companies and the introduction of the "Eötvös torsion balance" to standard equipment of their research groups.

In the mid-20th century, field measurements by the torsion balance were replaced by a new gravimetry system, shortening measurement time on the registration point and small dimensions of the apparatus lead to a substantial increase in the efficiency of exploration work. Despite the progress, torsion balance has remained on active duty up to this day and are still used in many geophysical observatories. The development continued and in March 2016 the researchers from the „University of Glasgow“ presented MEMS (Micro-electromechanical systems) detector capable of stable registration of the gravity field alteration. The sensitivity of the detector does not approach the standard gravimetry sensitivity but the sensitivity achieved is sufficient according to the constructors to register the impact of elements with significant density contrast.


The small original Eötvös torsion balance. Budapest: Ferdinand Süss Precision Mechanical and Optical Works, .

. The history of the 125 year old Eötvös torsion balance. Acta Geodaetica et Geophysica, () 51: 273. doi:10.1007/s40328-015-0126-4.

. Measurement of the Earth tides with a MEMS gravimeter. Nature (), pp. 614-617. doi:10.1038/nature17397.

. Úvod do užité geofyziky. Praha: SNTL - Nakladatelství technické literatury, . ISBN: 80-03-00427-6