Back when I was a wee lad (1980s) a lot of the Ray Bradbury books had cover art by a guy whose pictures were very geometric- they would typically be conglomerations of spheres and pyramids linked together to look like dragons and things like that. One very notable thing about his art was that the surfaces were all covered in finely spaced lines. IIRC, he did the cover art for The Martian Chronicles, Something Wicked this Way Comes, and I Sing the Body Electric.
I also have a vague memory that in the movie “Wizards” he did a few backgrounds depicting large ships.
I have The Stories Of Ray Bradbury, published in 1980. This is a collection of 100 of his stories, and the cover…is sort of hard to describe. It seems to be rays of light, emitted from the title words, pulling back at an angle towards a small almost square shape. I’m not sure if that’s what you meant by geometrical, but the cover art for this particular book was done by R. D. Scudellari.
I have a copy of the Illustrated Man (circa 76) - no illustrator mentioned. (Cool art - the illustrated man sitting on a rickety stand.) A 98 Something Wicked This Way Comes from Avon Books - lame cover. And a hardcover 22X2 Stories with no cover art at all.
It’s kind of hard to tell - some of his books have been through 30 printings, with various publishers. The ships from Wizards? Wasn’t that Roger Dean?