Yeah, those are first-generation diesel locos from the 1950’s, and the pix is dated 1979.
Those are ALCO diesels, from the American Locomotive Co (ALCO) and were famous for their black smoke when accelerating… not seen in this pix. I remember as a child seeing this type going by on the local railroad, and I could always tell the ALCOs by the peculiar steel rattle the engines made… like a bad valve job on your car!