Hi,
The vMotion events (normal vMotion and Storage vMotion) will be logged on your host.
(/var/log/vmware/hostd*.log) you wil be able to use the UUID of the VMFS datastore (vmfs/volumes/xxxxxx-xxxxxx-xxxx-xxxxxxxxx)
You can convert the UUID into the name given to the datastore from the console:
esxcli storage vmfs extent list