( ( These sediments ) ( ( ( buried ( ( large amounts ) ( of ( organic materials ) ) ) ) ( with them ) ) . ) )
(ROOT (S (NP (DT These) (NNS sediments)) (VP (VBD buried) (NP (NP (JJ large) (NNS amounts)) (PP (IN of) (NP (JJ organic) (NNS materials)))) (PP (IN with) (NP (PRP them)))) (. .)))
These sediments buried large amounts of organic materials with them.
(ROOT (S (NP (NP (NNS Sediments)) (PP (IN in) (NP (JJ oligotrophic) (NNS lakes)))) (VP (VBP contain) (NP (NP (JJ large) (NNS amounts)) (PP (IN of) (NP (JJ decomposable) (JJ organic) (NN matter))))) (. .)))