Let $\mathscr{X}/R$ be a model of $X$. We say that $\mathscr{X}$ is a dlt (divisorially log terminal) model of $X$ if the following conditions hold:

• -

  the pair $(\mathscr{X},\mathscr{X}_{k,\red})$ is log canonical in the sense of the Minimal Model Program (see [KM98]);

• -

  the pair $(\mathscr{X},\mathscr{X}_{k,\red})$ is simple normal crossing at the generic points of log canonical centers of $(\mathscr{X},\mathscr{X}_{k,\red})$.