He used a sound wave detector, which utilized sound waves to penetrate the ground.
Different sound wave patterns represented different materials.
The pattern of sound waves traveling through air was entirely different from that of sound waves moving through soil.
This was the convenience of using modern archaeological instruments.
Old Yao and Professor Qi looked at each other.
A hint of pride and arrogance appeared on Professor Qi's face, accompanied by a smile.
Old Yao, on the other hand, was delighted: "Keep probing, keep probing, cover a larger area."
Immediately, several other members of the archaeological team took up their detection equipment and expanded the probing range.
It didn't take long.
The archaeological team had completed the detection.
"Captain Yao, preliminary detection indicates that about fifteen meters below, there is a relatively spacious burial chamber, sealed, without any water layer."
