Which exploration method analyzes the chemical composition of rocks, soil, or sediment to guide resource discovery?

• A. Electromagnetic survey
• B. Geochemical testing
• C. Seismic survey
• D. Indicator minerals

Answer: (B)

The essential idea is identifying a method that directly examines what rocks and soils are made of. Geochemical testing does this by sampling rocks, soils, or sediments and analyzing their elemental and sometimes isotopic composition to find anomalies that point to concealed mineral deposits. This direct look at chemical makeup helps explorers spot areas with elevated or unusual concentrations that warrant closer investigation or drilling.

This differs from electromagnetic surveys, which map subsurface physical properties like conductivity, not chemistry. Seismic surveys reveal subsurface structures based on wave speeds, not elemental content. Indicator minerals can signal favorable conditions or environments for certain ore types, but they rely on subsequent chemical analyses to confirm the presence of a valuable deposit.