system tablespace is growing very large

My SYSTEM tablespace is growing very large (actually 4.4 GB)

I found several tables which are up to 680 MB with a high fragmentation rate. Row-Movement is disabled for all tables.

As well Indexes are fragmented (some are already bigger than ist tables)

How can I shrink or purge those tables?

(I am not sure if "shrink compact" is advisable)

My System is: Oracle Enterprise Edition 11.2.0.4 on AIX 6.1, Standalone DB

b.r.

Dieter

here the list of tables:

SQL> select table_name, row_movement ,num_rows,avg_row_len,round(blocks*8/1024) MB, round(blocks*7297/(avg_row_len+1)/(num_rows+1),1)"factor" from DBA_TABLES