Is database opened?
The fragment of the alert.log you posted woudl most probably leave the database just mounted.
I suspect the part of the aletr.log you posted is completely unrelated to the ora-3113 (please note, the part of the alert.log you posted contains ORA-00313 NOT ora-03113)

Ora-3113 is most oftenly caused by unexpected crash of the dedicated server process. Of cource if the database crashes, that would be the result too.
You'll need to find the trace file generated by the ora-3113 and it will probably contain the query which breaks the server.