Related Clues:
- Fracking target
- Sticky mammoth trapper
- Fuel oil source
- One of a La Brea group
- Rich source of fossils, perhaps
- Rock that's fracked
- Archaeological treasure trove
- Fossil-yielding sedimentary rock
- Say nothing, given drink that may be full of gas!
- Rock that's 'fracked'
- Oil-yielding mineral
- Dinosaur preserver
- Rock from which slate is formed
- Easily cleaved rock
- Oil source has excited the French