what sort of printing technique used in this quality print? Is offset lithog?

[Sunday Silence]

This is a British Library Board reproduction of Speeds Map of Scotland (1610). The print is dated 1977. When I look at it at 20x with my cheap loupe, I do not see rosettes. I do see repeat patterns in certain areas. I see checkerboards and hatching of one color in those shaded or half tone areas that you see. Presumably those boundary marks are made like that. The rest of the lines and bits of colors look continuous at this magnification, almost like stone lithography but they dont really seem to overlap with one another. I am guessing this is some sort of very fine offset lithog. but not sure. Are there other techniques used in making these sorts of fine quality prints? 


https://imgur.com/gallery/wF5PY

[erik1925]

Probably an offset kind of printing, perhaps using a high quality copy of the original 1610 map.