shield question

Thanks, Adrian. In a previous episode Njal 63, we have Sigurd swein head
carrying a flimsy shield (törguskjöld einbyrðan - single thickness? target
shield).
But what I wondered was if the shields were elongated ovals as the Norman's
carry on the Bayeux tapestry or if they were round as we see in so many
representations of Vikings on their ships. And if it is round, it would be
kind of hard to carry a man on his shield.
Grace
Fred and Grace Hatton
Hawley Pa