Not wrinkled; not having wrinkles or furrows; smooth; hence, flowing; even.

adjective. without wrinkles

adjective. not wrinkled or creased

"The mineral resource estimate is as of May 1, 2008 and was conducted using a combination of Ordinary Kriging (gold) and Inverse-Distance Weighting (silver) grade interpolations within an 'unwrinkled' 3-D block model in Gemcom software."

blue-veined  co-working  death-cold  dome-like  flyaway  

wrinkle-free