An evolutionist is one who accepts evolution as a theory or fact, just as a creationist is one who accepts creation as a theory or a fact.  Evolutionary is a simple adjective, just a creationary is a simple adjective.  A geologist who is an evolutionist promotes evolutionary geology.  A geologist who is an creationist promotes creationary geology.  There is no such thing as "neutral" geology.  All scientifically studied geology is interpreted within a paradigm.  S. J. Gould said in Time's Arrow, Time's Cycle, (paraphrased) First you determine the assumptions within which you do geology, then you go to the outcrop, not the other way around.  Either you start with naturalism's uniformitarianism / actualism or you start with creationism's catastrophism.  There is no middle ground.