Both post image and featured image showing on archive page

I’m using WordPress 3.7.1 with the Genesis Framework and the Dynamik child theme.

On the archives pages, both the featured image and the regular post image appear side by side. I want the featured image (thumbnail) to appear on the archive page and the regular image to appear on the single-post page.

Here’s a link:
https://vacationsinclusive.com/category/featured/

Thanks.