A tablespace export is specified using the TABLESPACES parameter. In tablespace mode, only the tables contained in a specified set of tablespaces are unloaded. If a table is unloaded, then its dependent objects are also unloaded. Both object metadata and data are unloaded. In tablespace mode, if any part of a table resides in the specified set, then that table and all of its dependent objects are exported. Privileged users get all tables. Unprivileged users get only the tables in their own schemas.
"TABLESPACES" for a description of the Export TABLESPACES parameter