Google ranks folders higher than pages

Traffic to "Images" and "Directories" folders rivals index

[insyte1]

I have a site serviced mainly by Google. For some reason,it has decided to direct raffic to the folders holding various groups of pages, traffic equalling or even exceeding that going to the index page.

I have a group of subject-specific pages sitting in a "Directories" folder. Google is directing traffic massively not to the pages themselves, but to this folder. So according to my cPanel stats, /Directories/ gets more traffic even than /index!

Today I find a big chunk of traffic being directed to /Images/, the folder holding all my image jpgs. Same for /Articles/, the folder holding pages of articles.

What is it about these folders that is so attrative to Google that it treats them like an information page and ranks them so well?