| # | Clue | Answer As Given | Value | Round | Category | Air Date | Show |
|---|---|---|---|---|---|---|---|
| William Smith's 1815 map "of England and Wales" showed these rock layers in different colors | strata | $2,000 | DJ | GEOLOGY | 2006-11-24 | #5110 | |
| Term for layers of rock having the same composition throughout | strata | $800 | DJ | ROCKS & MINERALS | 1990-12-05 | #1443 |