earthworks or land art,art form developed in the late 1960s and early 70s by Robert Smithson, Robert Morris, and others, in which the artist employs the elements of nature in situ or rearranges the landscape with earthmoving equipment. The resulting work, often vast in scale, is subject to all natural changes, such as temperature variations, light and darkness, wind, and erosion. The technique was in part an attempt to counter the perception of art as an acquirable commodity. Smithson's Spiral Jetty (1970), a huge spiral of rock and salt crystal in the middle of the Great Salt Lake, Utah, is a characteristic example of the earthwork form. Because of the fluctuating water level of the lake, Spiral Jetty is not always visible. Another notable earthworks artist is Michael Heizer, whose vast City (1971–) in the Nevada desert, is probably the largest such work yet attempted. Still another monumental earthwork is James Turrell's Roden Crater, an extinct volcano near Flagstaff, Ariz., the interior of which he has transformed since the 1970s into an enormous work of art with rooms, tunnels, and openings to the sky. Among other artists working in this genre are Dennis Oppenheim, Alice Aycock, Nancy Holt, Richard Long, Walter de Maria Newton, and Helen Harrison.
