There is no real way of archiving a thread, per se. Admins and moderators can move threads to other forums called "Archive", so it looks like archiving even when it isn`t. That`s just so you know what`s really happening.
If you want a thread in Economic Fundamentals Research moved to the archive, send a PM to an administrator with a link to the thread(s) (we can`t go chasing down where threads are located), or use the Report button on each thread. The first option is preferred if you can give the links, since it only sends the message to one person. However, I indicate the report feature for those who aren`t quite sure how to copy or paste links (though there is a post
here that explains how).
Make sure to let us know what you want done with it.
Cheers!