Post-seismic mantle relaxation in the Central Nevada Seismic Belt detected by InSAR: Implication for Basin and Range dynamics
Noel Gourmelen(1) and Falk Amelung(1)
University of Miami - RSMAS,
4600 Rickenbaker Causeway,
Acceleration of deformation during the Holocene and post-seismic deformation have been the two favored mechanisms to explain the high present-day deformation rate in the Central Nevada Seismic Belt (CNSB). Discriminating between the two mechanisms is critical to understand the dynamics of the Basin and Range lithosphere. Interferometric synthetic aperture radar data (InSAR) acquired between 1992 and 2000 detect a broad area of uplift at a rate of 2-3 mm/yr in the CNSB. The observed uplift can be explained by a model of post-seismic relaxation following the 1915-1954. Deformation is caused by flow in the mantle underlying an elastic crust. The results lead to a broad agreement between geologic and geodetic strain indicators for this portion of the Basin and Range and support the simple tectonic picture in which the Central Basin and Range between the CNSB and the Wasatch fault behaves as a rigid block. The results do no support an elevated seismic potential for the CNSB.