( ( According ( to ( the study ) ) ) ( , ( ( the ( ( most important ) ( classification parameters ) ) ) ( ( are ( ( the ( geological ones ) ) ( describing ( ( the ( texture ( , ( structure ( , ( and composition ) ) ) ) ) ) ( of ( ( ( the ( excavated rocks ) ) and ) ( their ( country rocks ) ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (VBG According) (PP (TO to) (NP (DT the) (NN study)))) (, ,) (NP (DT the) (ADJP (RBS most) (JJ important)) (NN classification) (NNS parameters)) (VP (VBP are) (NP (NP (DT the) (JJ geological) (NNS ones)) (VP (VBG describing) (NP (NP (DT the) (NN texture) (, ,) (NN structure) (, ,) (CC and) (NN composition)) (PP (IN of) (NP (NP (DT the) (JJ excavated) (NNS rocks)) (CC and) (NP (PRP$ their) (NN country) (NNS rocks)))))))) (. .)))
According to the study, the most important classification parameters are the geological ones describing the texture, structure, and composition of the excavated rocks and their country rocks.
(ROOT (S (SBAR (WHADVP (WRB How)) (S (NP (NN ice) (NNS cores)) (VP (VBP are) (ADJP (JJ important) (PP (TO to) (NP (NP (DT the) (NN study)) (PP (IN of) (NP (JJ geologic) (NN history))))))))) (VP (VBZ is) (ADVP (RBS best)) (VP (VBN described) (SBAR (IN as) (S (NP (PRP they)) (VP (VBP contain) (NP (NN evidence) (NN showing) (NNS changes)) (PP (IN in) (NP (NP (DT the) (JJ atmospheric) (NN composition)) (PP (IN over) (NP (NN time)))))))))) (. .)))