Dictionary_BUILD_Goldengate_DB.txt

 execute DBMS_LOGMNR_D.BUILD( options => DBMS_LOGMNR_D.STORE_IN_REDO_LOGS);

You can build dictionaries at any time using

execute DBMS_LOGMNR_D.BUILD( options => DBMS_LOGMNR_D.STORE_IN_REDO_LOGS);

And subsequently search for the SCN of a data dictionary build using

column first_change# format 999999999999999

SELECT first_change#, to_char(first_time,  'yyyy-mm-dd hh24:mi:ss')  FROM v$archived_log WHERE dictionary_begin = 'YES' AND standby_dest = 'NO' AND name IS NOT NULL AND status = 'A';