( ( ( The ( plate boundary ) ) ( between ( the ( Indian ( and ( Asian ( continental masses ) ) ) ) ) ) ) ( ( provides ( ( ( ( ( ( ( a ( well-studied example ) ) , ) ( as ( ( ( the ( Tibetan Plateau ) ) ( ( just north ) ( of ( the boundary ) ) ) ) ( has ( ( crust ( ( about 80 ) kilometers ) ) thick ) ) ) ) ) , ) roughly ) twice ) ( ( the thickness ) ( of ( normal ( continental crust ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN plate) (NN boundary)) (PP (IN between) (NP (DT the) (JJ Indian) (CC and) (JJ Asian) (JJ continental) (NNS masses)))) (VP (VBZ provides) (NP (NP (NP (DT a) (JJ well-studied) (NN example)) (, ,) (SBAR (IN as) (S (NP (NP (DT the) (NNP Tibetan) (NNP Plateau)) (PP (ADVP (RB just) (RB north)) (IN of) (NP (DT the) (NN boundary)))) (VP (VBZ has) (VP (VBN crust) (NP (QP (RB about) (CD 80)) (NNS kilometers)) (ADVP (JJ thick))))))) (, ,) (RB roughly) (RB twice) (NP (NP (DT the) (NN thickness)) (PP (IN of) (NP (JJ normal) (JJ continental) (NN crust)))))) (. .)))
The plate boundary between the Indian and Asian continental masses provides a well-studied example, as the Tibetan Plateau just north of the boundary has crust about 80 kilometers thick, roughly twice the thickness of normal continental crust.
(ROOT (S (NP (NP (NP (DT The) (NN earth) (POS 's)) (JJ continental) (NN crust)) (, ,) (PP (IN on) (NP (NN average))) (, ,)) (VP (VBZ is) (ADJP (NP (CD 35) (NNS kilometers)) (JJ thick))) (. .)))