How to set ADR Base directory correctly on OracleDB on Linux?
Just set:

diagnostic_dest=/u01/app/oracle


or

diagnostic_dest=/volumeX/app/oracle


The error message you receive indicates that the value for this parameter is currently stored in a format that the database can not interpret. When this happens, the database will search for this directory in $ORACLE_HOME/dbs as seen below the ORA-48140 line.

Or you can just simply delete this line, and the parameter value will default to $ORACLE_BASE.