( ( Seismic ( reflection ( and ( refraction images ) ) ) ) ( ( show ( that ( ( shallow-depth faults ) ( may ( underlie ( some ( of ( the ( observed ( surface cracks ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (JJ Seismic) (NN reflection) (CC and) (NN refraction) (NNS images)) (VP (VBP show) (SBAR (IN that) (S (NP (JJ shallow-depth) (NNS faults)) (VP (MD may) (VP (VB underlie) (NP (NP (DT some)) (PP (IN of) (NP (DT the) (ADJP (JJ observed)) (NN surface) (NNS cracks))))))))) (. .)))
Seismic reflection and refraction images show that shallow-depth faults may underlie some of the observed surface cracks.
(ROOT (S (NP (DT An) (NN image)) (VP (VBZ is) (NP (NP (DT a) (NN copy)) (PP (IN of) (NP (NP (DT an) (NN image)) (VP (VBN formed) (PP (IN by) (NP (NN reflection) (CC or) (NN refraction)))))))) (. .)))