The scientists used a method called magnetotelluric sounding to search for oil and gas in the Yingen-Ejin Banner basin in Inner Mongolia. By analyzing data from seven profiles, they identified layers of rock that could contain valuable resources. They accurately determined the depth and thickness of certain rock layers, helping to map out where oil and gas might be found. The results showed that magnetotelluric sounding is a useful tool for studying the geology of the area and could be important for future exploration efforts.