Suppose $(X,B)$ is a log canonical pair and $f: X \rightarrow Y$ an equidimensional toroidal contraction such that every component of $B$ is $f$ -horizontal. Let $\Gamma$ denote the reduced ramification divisor of $f$. I am required to show that $(X,B+ \Gamma)$ is log canonical.
Any comments, suggestions and references are welcome. Thanks in advance!
