Glacier Fields of snow become sheets of ice so massive that their very weight causes them to move.
(Glacier Fields of snow; become; sheets of ice so massive that their very weight causes them to move) (their very weight; causes; them to move) Context(their very weight causes,List([60, 84))):(them; to move; )
their very weight causes,List([60, 84))
Glacier Fields of snow their very weight them
become causes to move
sheets of ice so massive that their very weight causes them to move
them to move