Within
the basin lies an almost perfectly flat dry lake, known as the Racetrack
Playa.
Resting on its flat dry lakebed are pebble- to boulder-sized rocks, with masses estimated at up to 320 kilograms (Sharp and Carey, 1976).
The Racetrack Basin lies within the boundary of Death Valley National
Park.
Within
the basin lies an almost perfectly flat dry lake, known as the Racetrack
Playa.
Resting on its flat dry lakebed are pebble- to boulder-sized rocks,
with masses estimated at up to 320 kilograms (Sharp and Carey, 1976).
This in itself could be explained by simple mass wasting processes,
yet the position of the rocks, often hundreds of meters from a source area,
and the presence of furrows in the clay playa surface leading toward the
rocks suggests that the rocks are moving by traction. 
Trails
created by the rocks vary in length and direction. Some trails show
gradual (curving) or abrupt (angular) changes in direction; most trails
indicate a general south/southwest to north/northeast motion (Kirk, 1952;
Sharp and Carey, 1976). Distances traveled of as much as 3.2 kilometers
are inferred by the presence of distinctive lithologies far from possible
areas of origin. Many rocks appear to break off dolomite cliffs at
the south end of the playa, and are ultimately "deposited" where the playa
meets an alluvial fan, about 2 kilometers to the north (Sharp and Carey,
1976; Messina, Stoffer and Clarke, 1997). Some trails are parallel
to others that are in close proximity and generally strike from south to
north, consistent with prevailing wind patterns, thereby suggesting wind
as the motive force.
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