Welcome to the Forum.
Are you sure that it is engine oil, rather than gear oil (gear oil will have a peculiar smell)
If it is gear oil, it COULD be due to the gearbox being overfilled, or to a blocked vent. (As well as leaking from other places that is)
Suggest that you clean it all down with Jizer or Gunk and try to identify the source of the leak.
Regards.