Temperatures must be less than that which would produce melting, and fluids moving through the rock must be in concentrations below that which would saturate the rock with water and cause melting.
(Temperatures; must be; less than that) (concentrations below that; cause; melting) (that; would produce; melting) (fluids; moving; through the rock) (fluids moving through the rock; must be; in concentrations below that) (concentrations below that; would saturate; the rock; with water)
Temperatures concentrations below that that fluids fluids moving through the rock concentrations below that
must be cause would produce moving must be would saturate
less than that
melting
melting
through the rock
in concentrations below that
the rock with water