( ( In ( the ( clearest ( ocean water ) ) ) ) ( , ( ( the ( euphotic zone ) ) ( ( may ( extend ( ( ( ( ( ( ( to ( ( a depth ) ( of ( ( about 150 ) meters ) ) ) ) , ) or ) rarely ) , ) up ) ( to ( 200 meters ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (DT the) (JJ clearest) (NN ocean) (NN water))) (, ,) (NP (DT the) (JJ euphotic) (NN zone)) (VP (MD may) (VP (VB extend) (PP (PP (TO to) (NP (NP (DT a) (NN depth)) (PP (IN of) (NP (QP (RB about) (CD 150)) (NNS meters))))) (, ,) (CC or) (ADVP (RB rarely)) (, ,) (RB up) (PP (TO to) (NP (CD 200) (NNS meters)))))) (. .)))
In the clearest ocean water, the euphotic zone may extend to a depth of about 150 meters, or rarely, up to 200 meters.
(ROOT (S (NP (DT The) (JJ photic) (NN zone)) (VP (VBZ extends) (ADJP (NP (CD 200) (NNS meters)) (JJ deep))) (. .)))
The photic zone extends 200 meters deep.