In this theme, the footer widget has a logo.
To change this image, please follow below steps.
1) Upload your own image ( preferred size 250x45px , transparent preferred ) by going to wp-admin/media/add-new.
2) Grab the absolute path of uploaded image eg: http://yourdomain.com/image.jpg
3) Go to Appearance -> Widgets -> Footer 1 , Find LC:info & Social widget and page the absolute URL in the place of selected text in below image.