It's quilted oak that has been dyed. It may be a common oak, but there is a chance it's some other wood that shows strong medullary ray figure like banksia or leopardwood. But based on the grain I think it's some type of American oak.
The figure you are seeing here i quilted figure that was quartersawn.
It's not showing any quilt figure which would only appear on a flatsawn face. Instead the quartersawn grain is showing the waves of the wood together with strong medullary ray figure. It's an interesting effect, that was enhanced by dark dye. It's not bog oak, in bog oak the medullary ray cells turn silver and do not remain more colored than the rest of the wood, that happens with dying though.