ALL_REGISTERED_SNAPSHOTS

Remote snapshots of local tables that the user can see

Columns
   ___________________________
 
   OWNER
      Owner of the snapshot
   NAME
      The name of the snapshot
   SNAPSHOT_SITE
      Global name of the snapshot site
   CAN_USE_LOG
      If NO,this snapshot is complex and cannot fast refresh
   UPDATABLE
      If NO,the snapshot is read only
   REFRESH_METHOD
      Whether the snapshot uses rowid or primary key or object id for fast refresh
   SNAPSHOT_ID
      Identifier for the snapshot used by the master for fast refresh
   VERSION
      Version of snapshot
   QUERY_TXT
      Query defining the snapshot

Related:

Simon Sheppard
SS64.com