Walter De Maria, a reclusive American sculptor whose multifaceted achievement and sly Dadaist humor helped give rise to earthworks, Conceptual Art and Minimal art, on an often monumental scale, died on Thursday in Los Angeles.
He was best known for large-scale outdoor works that often involved simple if rather extravagant ideas or gestures: a SoHo loft filled with two feet of earth, for example, or a solid brass rod two inches in diameter and one kilometer long driven into the ground in Kassel, Germany, so that only its smooth top was visible (a work consistent with an artist who once noted that “the invisible is real”).