  We investigate variations of Brieskorn lattices over non-compact parameter
spaces, and discuss the corresponding limit objects on the boundary divisor. We
study the associated variation of twistors and the corresponding limit mixed
twistor structures. We construct a compact classifying space for regular
singular Brieskorn lattices and prove that its pure polarized part carries a
natural hermitian structure and that the induced distance makes it into a
complete metric space.
