( ( The ( continental crust ) ) ( ( is ( more ( dense ( than ( the ( oceanic crust ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (JJ continental) (NN crust)) (VP (VBZ is) (ADJP (RBR more) (JJ dense) (PP (IN than) (NP (DT the) (JJ oceanic) (NN crust))))) (. .)))
The continental crust is more dense than the oceanic crust.
(ROOT (S (NP (NNP Gabbro)) (VP (VBZ is) (NP (NP (DT a) (JJ dark) (JJ dense) (NN rock)) (SBAR (WHNP (WDT that)) (S (VP (MD can) (VP (VB be) (VP (VBN found) (PP (IN in) (NP (DT the) (JJ oceanic) (NN crust)))))))))) (. .)))
Gabbro is a dark dense rock that can be found in the oceanic crust.