    Sentence 1: When. rock . formations  are found -on-top of a fault that  have--not -been cut, then:. they. must,  be alder or younger than: the’ fault?    Sentence 2:-Faults are younger than.  the rocks they cut;. accordingly, if  a .fault is’ found. that’ penetrates  some .formations ‘but’ not those” -on  top of it, .then the. formations ‘that  were cut are-older than the fault,  and: the ones that:.are. not’ cut -must  be -younger’ than the fault.    