Final answer:
Mark Rothko is known as the pioneer of color field painting. This style of abstract painting emerged in New York City and is closely related to Abstract Expressionism.
Step-by-step explanation:
The pioneer of color field painting is Mark Rothko. Color field painting is a style of abstract painting that emerged in New York City during the 1950s and 1960s. It is closely related to Abstract Expressionism and was characterized by large spaces of solid color divorced from specific contexts. Artists like Rothko, as well as Frank Stella, Clyfford Still, Barnett Newman, Adolph Gottlieb, and Morris Louis, are known for their use of color field techniques in their work.