  We consider the initial value problem (IVP) associated to a Boussinesq type
system. After rewriting the system in an equivalent form of coupled KdV-type
equations, we prove that this is locally well-posed in $(H^s(\R^2))^4$,
$s>3/2$, using sharp smoothing estimates. Consequently we obtain the local
well-posedness result for the original system in $H^s\times \mathcal{V}^{s+1}$
for $s>3/2$ (see below for the definition of $\mathcal{V}^{s}$).
