Over the decade 1983--1993 the U.S. Geological Survey has measured the deformation of a 50-km-aperture trilateration network centered on Yucca Mountain, the proposed disposal site for high-level nuclear waste in the United States. The network was surveyed in 1983, 1984, and 1993. The average annual principal strain rates are 0.010¿0.020 μstrain/yr N90¿W¿24¿ and -0.009¿0.021 μstrain/yr N00¿E¿24¿, indicating no significant strain accumulation. The southeast corner of the network was disturbed on June 29, 1992, by the Little Skull Mountain earthquake (Ms=5.4), the epicenter of which is about 20 km southeast of the Yucca Mountain site. Using the seismically determined fault plane (dip 54¿S55¿E), we find that 0.580¿0.075 m of normal slip on a 5-km square rupture surface at a depth of about 8 km provides a good fit to the observed deformation in the southeast corner of the network. The inferred seismic moment is (4.4¿0.6)¿1017 N m, which compares well with the observed seismic moment of 4.1¿1017 N m.