Subsurface exploration is a branch of geotechnical engineering that focuses on investigating soil and rock formations beneath the earth's surface. This area of research involves using various techniques to study the physical and mechanical properties of subsurface materials in order to assess their suitability for construction projects, such as building foundations, tunnels, bridges, and dams. Some common methods of subsurface exploration include soil sampling, geophysical surveys, and borehole drilling. By analyzing data collected from these methods, engineers can make informed decisions about the design and construction of structures to ensure their stability and durability over time. Overall, subsurface exploration plays a crucial role in the field of geotechnical engineering by providing valuable information about the characteristics of the earth beneath our feet and helping to mitigate risks associated with construction in different geological environments.