  We calculate the star formation quenching timescales in green valley galaxies
at intermediate redshifts ($z\sim0.5-1$) using stacked zCOSMOS spectra of
different galaxy morphological types: spheroidal, disk-like, irregular and
merger, dividing disk-like galaxies further into unbarred, weakly-barred and
strongly-barred, assuming a simple exponentially-decaying star formation
history model and based on the H$_{\delta}$ absorption feature and the $4000$
\AA ~break. We find that different morphological types present different star
formation quenching timescales, reinforcing the idea that the galaxy morphology
is strongly correlated with the physical processes responsible for quenching
star formation. Our quantification of the star formation quenching timescale
indicates that disks have typical timescales $60\%$ to 5 times longer than that
of galaxies presenting spheroidal, irregular or merger morphologies. Barred
galaxies in particular present the slowest transition timescales through the
green valley. This suggests that although secular evolution may ultimately lead
to gas exhaustion in the host galaxy via bar-induced gas inflows that trigger
star formation activity, secular agents are not major contributors in the rapid
quenching of galaxies at these redshifts. Galaxy interaction, associated with
the elliptical, irregular and merger morphologies contribute, to a more
significant degree, to the fast transition through the green valley at these
redshifts. In the light of previous works suggesting that both secular and
merger processes are responsible for the star formation quenching at low
redshifts, our results provide an explanation to the recent findings that star
formation quenching happened at a faster pace at $z\sim0.8$.
