  We study the blow-ups of configuration spaces. These spaces have a structure
of what we call an Orlik-Solomon manifold; it allows us to compute the
intersection cohomology of certain flat connections with logarithmic
singularities using some Aomoto type complexes of logarithmic forms. Using this
construction we realize geometrically the sl_2 Bernstein - Gelfand - Gelfand
resolution as an Aomoto complex.
