( ( ( The difference ) ( in ( ( arrival time ) ( between ( ( P ( and ( S waves ) ) ) ( on ( a seismogram ) ) ) ) ) ) ) ( ( can ( be ( used ( to ( determine ( ( ( ( the distance ) ( of ( ( ( ( the station ) ( from ( the ( earthquake source ) ) ) ) and ) ( ( ( the amplitude ) ( -LRB- ( height -RRB- ) ) ) ( of ( the ( S wave ) ) ) ) ) ) ) ( recorded ( at ( ( the station ) ( can ( be ( used ( to ( determine ( earthquake magnitude ) ) ) ) ) ) ) ) ) ) ( -LRB- ( ( see ( Earthquake measurement ) ) -RRB- ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN difference)) (PP (IN in) (NP (NP (NN arrival) (NN time)) (PP (IN between) (NP (NP (NNP P) (CC and) (NNP S) (NNS waves)) (PP (IN on) (NP (DT a) (NN seismogram)))))))) (VP (MD can) (VP (VB be) (VP (VBN used) (S (VP (TO to) (VP (VB determine) (NP (NP (NP (DT the) (NN distance)) (PP (IN of) (NP (NP (NP (DT the) (NN station)) (PP (IN from) (NP (DT the) (NN earthquake) (NN source)))) (CC and) (NP (NP (NP (DT the) (NN amplitude)) (PRN (-LRB- -LRB-) (NP (NN height)) (-RRB- -RRB-))) (PP (IN of) (NP (DT the) (NNP S) (NN wave))))))) (VP (VBN recorded) (PP (IN at) (NP (NP (DT the) (NN station)) (SBAR (S (VP (MD can) (VP (VB be) (VP (VBN used) (S (VP (TO to) (VP (VB determine) (NP (NN earthquake) (NN magnitude))))))))))))) (PRN (-LRB- -LRB-) (S (VP (VB see) (NP (NN Earthquake) (NN measurement)))) (-RRB- -RRB-))))))))) (. .)))
The difference in arrival time between P and S waves on a seismogram can be used to determine the distance of the station from the earthquake source and the amplitude (height) of the S wave recorded at the station can be used to determine earthquake magnitude (see Earthquake measurement ).
(ROOT (S (NP (NP (DT The) (NN height)) (PP (IN of) (NP (DT the) (NN wave)))) (VP (VBZ is) (VP (VBN used) (S (VP (TO to) (VP (VB determine) (NP (NP (DT the) (NN magnitude)) (PP (IN of) (NP (DT an) (NN earthquake))))))))) (. .)))