Which map displays rock types in a stratigraphic unit and shows the location of sandstone within the formation?

• A. Isopach maps
• B. Tectonic maps
• C. Hypsometric map
• D. Lithofacies map

Answer: (D)

In sedimentary mapping, a lithofacies map shows the actual rock types within a stratigraphic unit and how they are distributed laterally. It highlights where different lithologies—such as sandstone, shale, or limestone—occur within a single formation, so you can see exactly where sandstone lies inside that interval. This is precisely what the question asks for: the location and spread of sandstone within the formation.

An isopach map, on the other hand, displays thickness variations of a unit across an area, not its internal rock types. A tectonic map focuses on structural features like faults and folds, not lithology. A hypsometric map shows surface elevation and topography, not subsurface rock composition.