History of Late Holocene Earthquakes at the Willow Creek Site and on the Nephi Segment, Wasatch Fault Zone, Utah


Book Description

This 43-page report presents new data from the Willow Creek site that provides well-defined and narrow bounds on the times of the three youngest earthquakes on the southern strand of the Nephi segment, Wasatch Fault zone, and refines the time of the youngest earthquake to about 200 years ago. This is the youngest surface rupture on the entire Wasatch fault zone, which occurred about a century or less before European settles arrived in Utah. Two trenches at the Willow Creek site exposed three scarp-derived colluvial wedges that are evidence of three paleoearthquakes. OxCal modeling of ages from Willow Creek indicate that paleoearthquake WC1 occurred at 0.2 ± 0.1 ka, WC2 occurred at 1.2 ± 0.1 ka, and WC3 occurred at 1.9 ± 0.6 ka. Stratigraphic constraints on the time of paleoearthquake WC4 are extremely poor, so OxCal modeling only yields a broadly constrained age of 4.7 ± 1.8 ka. Results from the Willow Creek site significantly refine the times of late Holocene earthquakes on the Southern strand of the Nephi segment, and this result, when combined with a reanalysis of the stratigraphic and chronologic information from previous investigations at North Creek and Red Canyon, yield a stronger basis of correlating individual earthquakes between all three sites.




Paleoseismic Investigation on the Salt Lake City Segment of the Wasatch Fault Zone at the South Fork Dry Creek and Dry Gulch Sites, Salt Lake County, Utah


Book Description

The South Fork Dry Creek and Dry Gulch sites lie within a few hundred meters of each other in the southeastern part of the Salt Lake Valley, and together provide the only location on the heavily urbanized Salt Lake City segment of the Wasatch fault zone where it is possible to develop a complete surface-faulting chronology for the segment since middle Holocene time (the past 6,000 years). Investigations at the two sites took place intermittently between 1985 and 1995 as permission was obtained to trench more and more of the scarps within the broad fault zone. The new information reported here on the size, timing, and especially recurrence of surface-faulting earthquakes on the Salt Lake City segment shows that the earthquake hazard presented by this segment of the Wasatch fault is greater than previously thought. Such information is vital to public officials, planners, and others making decisions regarding earthquake-hazard mitigation. 22 pages + 1 plate




The Oquirrh Fault Zone, Tooele County, Utah


Book Description

The two reports in this Special Study provide critical geologic and paleoseismic information on the Oquirrh fault zone, a Quaternary fault in eastern Tooele County, west-central Utah. The Oquirrh fault zone has long been recognized as a potential source of large earthquakes which could affect military and hazardous waste facilities, nearby towns, and populous areas of the more distant central Wasatch Front. 64 pages + 2 plates




The Wasatch Fault


Book Description

A beautifully designed and easy to understand publication discussing the geologic history of the Wasatch Fault and possible dangers it poses to anyone living nearby. This is a perfect introduction to the fault for anyone of all ages.







Consensus Preferred Recurrence-interval and Vertical Slip-rate Estimates


Book Description

This report presents the results of the Utah Quaternary Fault Parameters Working Group (hereafter referred to as the Working Group) review and evaluation of Utah’s Quaternary fault paleoseismic-trenching data. The purpose of the review was to (1) critically evaluate the accuracy and completeness of the paleoseismictrenching data, particularly regarding earthquake timing and displacement, (2) where the data permit, assign consensus, preferred recurrence-interval (RI) and vertical slip-rate (VSR) estimates with appropriate confidence limits to the faults/fault sections under review, and (3) identify critical gaps in the paleoseismic data and recommend where and what kinds of additional paleoseismic studies should be performed to ensure that Utah’s earthquake hazard is adequately documented and understood. It is important to note that, with the exception of the Great Salt Lake fault zone, the Working Group’s review was limited to faults/fault sections having paleoseismic-trenching data. Most Quaternary faults/fault sections in Utah have not been trenched, but many have RI and VSR estimates based on tectonic geomorphology or other non-trench-derived studies. Black and others compiled the RI and VSR data for Utah’s Quaternary faults, both those with and without trenches.




Paleoseismology


Book Description

Paleoseismology (the study of "ancient" earthquakes) has become an important component of seismic risk analysis, which is mandated for nuclear power plants, dams, waste repositories, and other critical structures. This book is the first in the English language to be devoted solely to paleoseismology. It summarizes the development of the field from the 1960s to the present, encompassing material that is currently widely dispersed in journal articles. The 10 chapters included in this text span the entire range of techniques currently used in paleoseismic reconstruction, and are contributed by active practitioners at the forefront of paleoseismic research. * First book solely devoted to paleoseismology * Summarizes the development of the field from the 1960's to the present * Includes a comprehensive review of the techniques currently used in paleoseismology * Emphasizes practical methods of data collection and field studies * Covers interpretation of field data based on current theory concerning fault segmentation and recurrence cycles * Contains more than 170 line drawings and 50 photographs of paleoseismic phenomena




Paleoseismic Investigation of the Northern Strand of the Nephi Segment of the Wasatch Fault Zone at Santaquin, Utah


Book Description

This CD contains a 33 page report, appendix, and plate. This study presents the results of fault-trench excavations near Santaquin, Utah, and includes discussion of (1) previous paleoseismic investigations on the Nephi segment, (2) the geology of the Santaquin trench site and excavations (3) paleoseismic results, including the timing of the most recent surface-faulting earthquake, fault displacement and slip rate, and surface-faulting earthquake recurrence and (4) implications for the segmentation of the southern Wasatch fault zone.




Treatise on Geomorphology


Book Description

The changing focus and approach of geomorphic research suggests that the time is opportune for a summary of the state of discipline. The number of peer-reviewed papers published in geomorphic journals has grown steadily for more than two decades and, more importantly, the diversity of authors with respect to geographic location and disciplinary background (geography, geology, ecology, civil engineering, computer science, geographic information science, and others) has expanded dramatically. As more good minds are drawn to geomorphology, and the breadth of the peer-reviewed literature grows, an effective summary of contemporary geomorphic knowledge becomes increasingly difficult. The fourteen volumes of this Treatise on Geomorphology will provide an important reference for users from undergraduate students looking for term paper topics, to graduate students starting a literature review for their thesis work, and professionals seeking a concise summary of a particular topic. Information on the historical development of diverse topics within geomorphology provides context for ongoing research; discussion of research strategies, equipment, and field methods, laboratory experiments, and numerical simulations reflect the multiple approaches to understanding Earth’s surfaces; and summaries of outstanding research questions highlight future challenges and suggest productive new avenues for research. Our future ability to adapt to geomorphic changes in the critical zone very much hinges upon how well landform scientists comprehend the dynamics of Earth’s diverse surfaces. This Treatise on Geomorphology provides a useful synthesis of the state of the discipline, as well as highlighting productive research directions, that Educators and students/researchers will find useful. Geomorphology has advanced greatly in the last 10 years to become a very interdisciplinary field. Undergraduate students looking for term paper topics, to graduate students starting a literature review for their thesis work, and professionals seeking a concise summary of a particular topic will find the answers they need in this broad reference work which has been designed and written to accommodate their diverse backgrounds and levels of understanding Editor-in-Chief, Prof. J. F. Shroder of the University of Nebraska at Omaha, is past president of the QG&G section of the Geological Society of America and present Trustee of the GSA Foundation, while being well respected in the geomorphology research community and having won numerous awards in the field. A host of noted international geomorphologists have contributed state-of-the-art chapters to the work. Readers can be guaranteed that every chapter in this extensive work has been critically reviewed for consistency and accuracy by the World expert Volume Editors and by the Editor-in-Chief himself No other reference work exists in the area of Geomorphology that offers the breadth and depth of information contained in this 14-volume masterpiece. From the foundations and history of geomorphology through to geomorphological innovations and computer modelling, and the past and future states of landform science, no "stone" has been left unturned!