( It ( ( ( has also ) ( ( ( helped ( them ( ( explore ( important ( geologic phenomena ) ) ) ( in ( a ( difficult-to-explore region ) ) ) ) ) ) , ) ( including ( ( ( the fate ) ( of ( crustal plates ) ) ) ( that ( ( plunge ( back down ) ) ( into ( ( ( the mantle ) and ) ( ( the causes ) ( of ( earthquakes ( at ( great depths ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (PRP It)) (VP (VBZ has) (ADVP (RB also)) (VP (VBN helped) (S (NP (PRP them)) (VP (VB explore) (NP (JJ important) (JJ geologic) (NNS phenomena)) (PP (IN in) (NP (DT a) (JJ difficult-to-explore) (NN region))))) (, ,) (PP (VBG including) (NP (NP (DT the) (NN fate)) (PP (IN of) (NP (JJ crustal) (NNS plates))) (SBAR (WHNP (WDT that)) (S (VP (VBP plunge) (ADVP (RB back) (RB down)) (PP (IN into) (NP (NP (DT the) (NN mantle)) (CC and) (NP (NP (DT the) (NNS causes)) (PP (IN of) (NP (NP (NNS earthquakes)) (PP (IN at) (NP (JJ great) (NNS depths))))))))))))))) (. .)))
It has also helped them explore important geologic phenomena in a difficult-to-explore region, including the fate of crustal plates that plunge back down into the mantle and the causes of earthquakes at great depths.
(ROOT (S (NP (NNS Earthquakes)) (VP (VBP mark) (NP (NP (DT the) (NNS motions)) (PP (IN of) (NP (NP (VBG colliding) (NNS plates)) (CC and) (NP (NP (DT the) (NNS locations)) (SBAR (WHADVP (WRB where)) (S (NP (NNS plates)) (VP (VBP plunge) (PP (IN into) (NP (DT the) (NN mantle))))))))))) (. .)))