These are not chambray pants. The color of the blues ones is a chambray color but the fabric of the pants is a lightweight denim.
'Chambray is a lightweight, cotton fabric woven with a plain weave where the warp is a colored yarn and the weft is white. This results in a fabric that's softer, lighter, and more breathable than denim, making it ideal for warmer weather garments like shirts, dresses, and blouses. The weight of linen, but has no striation.