Why the archive sub pages are still indexed by Google?

[MichaelNewman]

Why the archive sub pages are still indexed by Google? I am using the WordPress SEO by Yoast, and selected the needed option to get these pages no-index  in order to avoid the duplicate content.

[simon_realbuzz]

Much depends on when you added the nofollow. It can take time for Google to recrawl your pages and discover the nofollow direction, so just keep an eye on it.

[MichaelNewman]

Thank you Simon, do you have an idea how much time is needed?

[simon_realbuzz]

No one can say with any certainty as it varies from site to site and depends how frequently your site is crawled, so all I can say is patience is key.  I've know some pages on our sites removed from the index within a week and others take far longer.

[Stramark]

Google Can and will index pages, even after nofollow links are added. It might me that a different domain is linking to that page thus the nofollow is rendered useless.

The yoast plugin adds a noindex.  The noindex is only applied after recrawling plus some day's. you can check this in google by looking "in cache" and see the date.

Even so, google still can and sometimes will index it. (eg if you do noindex on you whole domain, google will still hold you homepage in google for a long time) Google makes a decision based on their parameters.