What geophysical method is most effective for mapping deeply buried bedrock pediments at a depth of 1500 feet?

Seismic reflection is particularly effective for mapping deeply buried bedrock pediments because this method utilizes the reflection of seismic waves generated by an energy source, such as a small explosion or a hammer strike. As these waves travel through the earth, they encounter different geological layers, including bedrock, which reflect some of the waves back to the surface. Analyzing these reflected waves allows geophysicists to create detailed images of subsurface geology at significant depths, making it possible to identify and map structures like bedrock pediments located 1500 feet below the surface.

In contrast, while magnetic surveying can detect variations in the Earth's magnetic field caused by different rock types, it is not as effective for deep subsurface mapping as it primarily focuses on relatively shallow targets. Electrical resistivity can provide valuable information about subsurface materials based on their conductivity but generally works best for shallower targets and may have limitations when assessing deeper geological formations due to increased complexity in the data. Gravity surveys measure variations in the Earth's gravitational field which can indicate subsurface density changes, but they are less precise than seismic reflection for identifying specific geological layers like bedrock and its depth.