( There ( ( were ( faults ( on ( both sides ) ) ) ) . ) )
(ROOT (S (NP (EX There)) (VP (VBD were) (NP (NP (NNS faults)) (PP (IN on) (NP (DT both) (NNS sides))))) (. .)))
There were faults on both sides.
(ROOT (S (NP (DT A) (NN fault)) (VP (VBZ is) (NP (NP (DT the) (NN fracture)) (VP (VBN caused) (SBAR (WHADVP (WRB when)) (S (NP (NP (NNS rocks)) (PP (IN on) (NP (DT both) (NNS sides)))) (VP (VBP move))))))) (. .)))