Appendix I

We present a new empirical ground motion model for PGA, PGV, PGD and 5% damped linear elastic response spectra for periods ranging from 0.01–10 s. The model was developed as part of the PEER Next Generation Attenuation (NGA) project. We used a subset of the PEER NGA database for which we excluded recordings and earthquakes that were believed to be inappropriate for estimating free-field ground motions from shallow earthquake mainshocks in active tectonic regimes.

A tectonic boundary should be defined by changes in tectonic elements. Tectonic elements would include such parameters as structural style, stress orientations, volcanism, heat flow, seisrnicity and changes in crustal thickness. Examination of these tectonic elements for the southern Colorado Plateau suggests that the southwestern part of the physiographic plateau appears to be tectonically part of the Basin and Range province.

This paper contains ground-motion prediction equations (GMPEs) for average horizontal-component ground motions as a function of earthquake magnitude, distance from source to site, local average shear-wave velocity, and fault type.

This study presents effective probabilistic procedures for evaluating ground-motion hazard at the free-field surface of a nonlinear soil deposit located at a specific site.

The purpose of this study was to gather and analyze previously unused data that led to improved locations for the 1906 (Ms 6.2), 1910 (Ms 6.0) and 1912 (Ms 6.2) northern Arizona earthquakes. Both ground shaking intensity patterns and instrumental data were used. The objective is to provide epicenter locations accurate enough to allow planners to decide what ground acceleration levels are most appropriate for northern Arizona.

Ground-motion prediction (attenuation) models predict the probability distributions of spectral acceleration values for a specified earthquake event. In this article a large number of strong ground motions are used to empirically estimate these correlations, and nonlinear regression is used to develop approximate analytical equations for their evaluation.

The commonly used Uniform Hazard Spectrum (UHS) is shown here to be an unsuitable target for this purpose, as it conservatively implies that large-amplitude spectral values will occur at all periods within a single ground motion. An alternative, termed a Conditional Mean Spectrum (CMS), is presented here.

The Sugarloaf fault is a slightly arcuate, northwest-southeast trending fault located near the junction of Mesquite Wash and Sycamore Creek. The fault was identified by Fugro (1981), which considered the fault in itsMCE analysis for Stewart Mountain Dam because of the evidence for possible Quaternary activity along the structure.

Starting with geological data, this paper estimates the seismicity for applications in seismic risk studies. The rate at which seismic moment is released can be estimated on a fault when the slip rate is known. Then, provided all of the deformation is released seismically, by assuming the relative frequency of different sizes of earthquakes, the absolute frequency of events can be obtained.

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