Dennis Oppenheim, a pioneer...

...of earthworks, body art and Conceptual art, died at age 72 (my emphasis):

Belonging to a generation of artists who saw portable painting and sculpture as obsolete, Mr. Oppenheim started out in the realm of the esoteric, the immaterial and the chronically unsalable. But he was always a showman, not averse to the circuslike, or to courting danger. For “Rocked Circle — Fear,” a 1971 body art piece, he stood at the center of a five-foot-wide circle painted on a New York sidewalk while a friend dropped fist-size stones from three stories above, aiming for inside the circle without hitting the artist. There were no mishaps.

Mr. Oppenheim's survivors include his third wife, Amy Van Winkle Plumb.