Can I keep different tunnel interfaces in different OSPF areas. Keep in mind that the physical interface is going to be the same
A large OSPF domain is typically broken into separate areas to restrict the propagation of routes and reduce the amount of resources required by each router to maintain its link state database. Each area is connected to a central backbone, area zero. Splitting them into more manageable areas can help speed traffic along to it's destination.
So answering your question, Yes you can keep different tunnel interfaces in different OSPF areas. You can check out the following link if its helpful: https://www.cisco.com/c/en/us/support/docs/security-vpn/ipsec-negotiation-ike-protocols/14381-gre-ipsec-ospf.html