  We present kinematic measurements of thin and thick disk components in a
sample of nine edge-on galaxies. We extract stellar and ionized gas rotation
curves at and above the galaxies' midplanes using the Ca II triplet absorption
features and H-alpha emission lines measured with the GMOS spectrographs on
Gemini North and South. For the higher mass galaxies in the sample, we fail to
detect differences between the thin and thick disk kinematics. In the lower
mass galaxies, there is a wide range of thick disk behavior including thick
disks with substantial lag and one counter-rotating thick disk. We compare our
rotation curves with expectations from thick disk formation models and conclude
that the wide variety of thick disk kinematics favors a formation scenario
where thick disk stars are accreted or formed during merger events as opposed
to models that form thick disks through gradual thin disk heating.
