Documents

This technical memorandum was prepared to document results and analysis of a 60-day pumping test conducted at hydrologic test well HRES-07.

Hydrologic test wells HRES-01, HRES-02, HRES-03, HRES-04, and HRES-05 were drilled and constructed during the period February 2 to March 11, 2004. The test wells were drilled evaluate lithologic and hydrogeologic conditions within the Apache Leap Tuff, and were terminated in the uppermost part of the Whitetail Conglomerate. Final test well construction was designed to permit hydrologic testing of the Apache Leap Tuff aquifer, and to provide access for long-term monitoring of groundwater level and groundwater quality for the aquifer.

This data summary report summarizes laboratory testing procedures and test results that were completed on concentrate produced during mineral processing, feedstock material, and metallurgical testing (rougher, cleaner, and whole) tailings produced from the lock cycle float tests.

This report is an addendum to several previous reports that include detailed analysis and discussion of hydrochemical sampling results for surface water and groundwater in the Upper Queen Creek/Devils Canyon (QCDC) study area.

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.