Which map shows geologic formation either exposed or overlain by surface deposits?

• A. Isoplets
• B. Planimetric Map
• C. Bedrock Map
• D. Thematic Map

Answer: (C)

Bedrock maps are designed to show the distribution of rock units at or near the surface, including where rock is exposed and where it lies beneath surface deposits. This type of map focuses on the actual rock formations and their boundaries, even when they are buried by soil or other unconsolidated material. That makes it the best fit for showing geologic formations that are either exposed or overlain by surface deposits.

Planimetric maps simply show horizontal positions and shapes of features without detailing rock types. Thematic maps focus on a specific topic (like rainfall or population) rather than geology. Isoplets are lines of equal value for a variable but aren’t used to depict bedrock units.