Studio director Elizabeth Childress told The New York Times De Maria, who lived in New York, was in Los Angeles to celebrate his mother's 100th birthday. De Maria died in his sleep Thursday, she said.
De Maria's unique and challenging works included a loft in Manhattan's trendy SoHo district was filled with 2 feet of dirt, the newspaper said. Another was 1 kilometer-long (0.62 mile) brass rod driven into the ground in Germany.
He said the shiny top was left visible to demonstrate that "the invisible is real."
One of his most notable projects was "The Lightning Field" in New Mexico, which was built in 1977 and consisted of 400 steel poles planted in the ground as lightning rods. The Times said the work rarely attracted actual lightning strikes, but was striking visually at sunrise or sunset.
Funeral plans were not immediately announced.