  This paper extends the models of Craig & McClymont (1991) and McLaughlin &
Hood (2004) to include finite $\beta$ and nonlinear effects. We investigate the
nature of nonlinear fast magnetoacoustic waves about a 2D magnetic X-point. We
solve the compressible and resistive MHD equations using a Lagrangian remap,
shock capturing code (Arber et al. 2001) and consider an initial condition in $
{\bf{v}}\times{\bf{B}} \cdot {\hat{\bf{z}}}$ (a natural variable of the
system). We observe the formation of both fast and slow oblique magnetic
shocks. The nonlinear wave deforms the X-point into a 'cusp-like' point which
in turn collapses to a current sheet. The system then evolves through a series
of horizontal and vertical current sheets, with associated changes in
connectivity, i.e. the system exhibits oscillatory reconnection. Our final
state is non-potential (but in force balance) due to asymmetric heating from
the shocks. Larger amplitudes in our initial condition correspond to larger
values of the final current density left in the system. The inclusion of
nonlinear terms introduces several new features to the system that were absent
from the linear regime.
