Since coal contains sulfur, the rocks directly above the coal are also rich in sulfur because they share the same elements of that environment.
(coal; contains; sulfur) (the rocks directly above the coal; are also; rich in sulfur; because they share the same elements of that environment) (they; share; the same elements of that environment)
coal the rocks directly above the coal they
contains are also share
sulfur
rich in sulfur because they share the same elements of that environment
the same elements of that environment