Electromagnetic surveying is a geophysical method used to measure the Earth's electromagnetic fields. This technique helps identify subsurface materials by analyzing how they respond to electromagnetic waves. It is commonly used in mineral exploration, environmental studies, and archaeological investigations. The process involves sending electromagnetic signals into the ground and measuring the response. Different materials, such as metals or water, affect the signals in unique ways, allowing scientists to map the subsurface structure. This non-invasive method provides valuable information without the need for drilling or excavation.