Seismic refraction is a geophysical method that uses seismic waves to determine the structure and properties of the Earth's subsurface.

Gravity surveys measure variations in the Earth's gravitational field, which are caused by variations in the density of subsurface materials.

Magnetotellurics is a geophysical method that uses naturally occurring electromagnetic fields to study the Earth's electrical conductivity structure.

Electrical resistivity imaging involves injecting electrical current into the ground and measuring the resulting potential differences to determine the electrical resistivity of the subsurface.

Ground-penetrating radar uses high-frequency electromagnetic waves to investigate shallow subsurface structures, such as buried objects, geological formations, and groundwater.

Seismic tomography is a geophysical technique that uses seismic waves to create images of the Earth's interior, providing insights into its structure and composition.

Magnetics is a geophysical method that measures the Earth's magnetic field, which is influenced by the presence of magnetic minerals and structures in the subsurface.

Microgravity surveys are commonly used to map geological structures, such as faults, folds, and subsurface cavities, by measuring subtle variations in the Earth's gravitational field.

Seismic reflection is a geophysical method that uses seismic waves to create high-resolution images of the Earth's subsurface by recording the reflections of seismic waves from subsurface layers.

Magnetotelluric soundings involve measuring variations in the Earth's magnetic field and electric field at the surface to study the Earth's electrical conductivity structure.

Magnetics is commonly used to detect buried metallic objects because magnetic anomalies are caused by the presence of magnetic materials, such as iron and steel.

Electrical resistivity tomography is often used to study groundwater flow patterns by measuring the electrical resistivity of the subsurface, which is influenced by the presence of water and its salinity.

Seismic refraction is a geophysical method that uses seismic waves to study the Earth's crust and upper mantle by recording the refractions of seismic waves at subsurface boundaries.

Gravity surveys involve measuring variations in the Earth's gravitational field, which are caused by variations in the density of subsurface materials.

Magnetotellurics is a geophysical method that utilizes electromagnetic fields to study the Earth's subsurface conductivity structure by measuring naturally occurring electromagnetic fields.