Redirect indexed lightbox URLs?

[Alces]

Hello all,

So I'm doing some technical SEO work on a client website and wanted to crowdsource some thoughts and suggestions. Without giving away the website name, here is the situation:

The website has a dedicated /resources/ page. The bulk of the Resources are industry definitions, all encapsulated in colored boxes. When you click on the box, the definition opens in a lightbox with its own unique URL (Ex: /resources/?resource=augmented-reality).

The information for these colored lightbox definitions is pulled from a normal resources page (Ex: /resources/augmented-reality/).

Both of these URLs are indexed, leading to a lot of duplicate indexed content.

How would you approach this?

**Things to Consider: **

-Website is built on Wordpress with a custom theme.
-I have no idea how to even find settings for the lightbox (will be asking the client today).
-Right now my thought is to simply disallow the lightbox URL in robots.txt and hope Google will stop crawling and eventually drop from the index.
-I've considered adding the main resource page canonical to the lightbox URL, but it appears to be dynamically created and thus there is no place to access (outside of the FTP, I imagine?).

I'm most rusty with stuff like this, so figured I'd appeal to the masses for some assistance. Thanks!

-Brad