  We study the propagation of high peaks (intermittency front) of the solution
to a stochastic heat equation driven by multiplicative centered Gaussian noise
in $\mathbb{R}^d$. The noise is assumed to have a general homogeneous
covariance in both time and space, and the solution is interpreted in the
senses of the Wick product. We give some estimates for the upper and lower
bounds of the propagation speed, based on a moment formula of the solution.
When the space covariance is given by a Riesz kernel, we give more precise
bounds for the propagation speed.
