It looks like these are the archived version of the redo log.
The archived log are used when you restored your database and want to recover the changes made after the backup you used to recover.
(the following commands are for Oracle 10g & 11g. They might have changed since 9i)
If you backup your database using RMAN, you can include the archived log using the following command:
RMAN> backup database plus archivelog;
You can also delete the archived log included in your backup by adding the "delete all input" statement:
RMAN> backup database plus archivelog delete all input;
Considering the numbers of files I recommend that you bounce your database, perform a full backup, delete the old archived log and purge the archive log list before.
You can purge the archive log list from an RMAN prompt using the following command:
RMAN> crosscheck archivelog all;
You should also change the folder where the archived log are stored using the following commands:
SQL> ALTER SYSTEM set log_archive_dest_1="LOCATION=x:\Whatever\The\Path" scope=spfile;
SQL> shutdown immediate;
SQL> alter system switch logfile;