Documents

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.

It is well known that the most widely used earthquake magnitude scales, ML (local magnitude), M, (surface wave magnitude), and mb (body wave magnitude), are, in principle, unbounded from above. It is equally well known that, in fact, they are so bounded, and the reasons for this are understood in terms of the operation of finite bandwidth instrumentation on the magnitude-dependent frequency characteristics of the elastic radiation excited by earthquake sources.

We mapped and characterized Quaternary site conditions using shear-wave-velocity (Vs)-profile data for basins along the Wasatch Front urban corridor to provide a basis for estimating soil response during earthquake ground shaking.

Have earthquakes strong enough to rupture the ground surface occurred on faults in central Arizona during the recent geologic past? Could such earthquakes happen in the future? If so, where are they most likely to occur? The Seismotectonics and Geophysics Section of the U.S. Bureau of Reclamation has, during the last 6 years, been working on answering these questions

Probabilistic seismic hazard analysis (PSHA) has become a fundamental tool is assessing seismic hazards and for estimating seismic design and seismic safety evaluation of ground motions. It is used on a site-specific basis for important and critical facilities and on a national scale for building codes. This report describes a project to test and verify the numerical approaches and software used in PSHA.

After more than a century of research, geologists and other scientists have increased their understanding of the tectonic processes at work in the Wasatch Front and are now beginning to answer the questions about the seismicity and tectonics of the Wasatch Front that Gilbert and others first posed Scientists, engineers, architects, urban planners, and emergency managers are not waiting for a major earthquake disaster to learn that measures must be implemented to mitigate an earthquake's effects.

A series of stream gauges is located within the upper Queen Creek, Devil’s Canyon, and Mineral Creek watersheds, located near Superior, AZ. These gauges are owned and maintained by Resolution Copper Mining (RCM). The historical stream gauge records were analyzed by JE Fuller Hydrology & Geomorphology, Inc in order provide an assessment of the quantity and quality of the surface water data. These data were also used to characterize and quantify volumetric surface water discharge characteristics in the three watersheds.

This Modeling Plan includes a description of the methods and data sets that are planned to be used in the air quality modeling analyses to estimate the Resolution Project’s air quality impacts relative to the applicable Ambient Air Quality Standards (AAQS) for criteria pollutants.

Onionweed is an aggressive invasive weed in the United States with significant infestations in Arizona and New Mexico.

Map and game species overview of Unit 24A