  We study the details and time dependence of particle production in nuclear
collisions at a fixed target beam energy of $E_{\mathrm{lab}}= 1.76$ A GeV with
the UrQMD transport model. We find that the previously proposed production
mechanism for multi strange hadrons, $\phi$ and $\Xi$, are possible due to
secondary interactions of incoming nuclei of the projectile and target with
already created nuclear resonances, while the Fermi momenta of the nuclei play
only a minor role. We also show how the centrality dependence of these particle
multiplicities can be used to confirm the proposed mechanism, as it strongly
depends on the number of participants in the reaction. Furthermore we
investigate the time dependence of particle production in collisions of Ca+Ca
at this beam energy, in order to understand the origins of the apparent
chemical equilibration of the measured particle yields. We find that indeed the
light hadron yields appear to be in equilibrium already from the very early
stage of the collision while in fact no local equilibration, through multi
collision processes, takes place. The apparent equilibrium is reached only
through the decay of the resonances according to available phase space.
