Mohammad Ashouri - Master of Natural Geography, Geomorphology, Faculty of Planning and Environmental Sciences, TabrizUniversity, East Azarbaijan Province, Iran

Geophysics is the study of the physics of the Earth and its environment in space. One emphasis isthe exploration of the Earth's interior using physical properties measured at or above the Earth'ssurface, together with mathematical models to predict those properties. Subdisciplines includeseismology, the study of seismic waves; geomagnetism, the study of the magnetic field; and geodesy,the study of the gravitational field and the shape of the Earth's surface. Seismology provides keyevidence for large-scale Earth structure and for the behavior of earthquakes. Mineralogy, and hencedensity and other physical properties at depth, is deduced from experiments and mathematicalmodeling in mineral physics. Mathematical models underpinning geophysics also predict the largescalemovements within the Earth (geodynamics). Generally Geophysics is one of the main branchesof earth science, which deals with natural phenomena as well as the behavior of the earth and itssurroundings. In general, geophysics is divided into two branches: pure geophysics and appliedgeophysics. Its pure part includes the trend of seismology. In the practical part, the quantitative studyof different physical properties of the earth is done using seismic, magnetic, gravimetric and electricalmethods. Natural hazards are one of the factors that cause financial losses every year and occur inmost regions of the world, including Iran. One of the dangers that humanity has faced in recentdecades, especially in alluvial plains, is the phenomenon of land subsidence and sinkholes. Landsubsidence and sinkholes due to natural and human causes have been reported in many places.Subsidence damages human structures supported by the earth. Land subsidence is the most importantenvironmental problem in Iran. The main cause of this phenomenon is the indiscriminate exploitationof underground water resources, which has led to land subsidence, and the extraction of undergroundwater plays an important role in causing land subsidence. In this article, we review and study theapplications of geophysics to detect sinkholes and land subsidence.

Geophysic, Sinkholes, Land Subsidence, Earth.