Characteristics, Causes, and Implications of the 1998 Wasatch Front Landslides, Utah
Characteristics, Causes, and Implications of the 1998 Wasatch Front Landslides, Utah

Author: Francis X. Ashland

Publisher: Utah Geological Survey

Published: 2003

Total Pages: 55

ISBN-13: 1557916896

DOWNLOAD EBOOK

The majority of the 1998 Wasatch Front landslides were likely triggered following a cumulative rise in ground-water levels resulting from four or more successive years of above-normal precipitation. Triggering of landslide movement likely coincided with a transient ground-water-level rise associated with the spring snowmelt and contemporaneous above-normal precipitation. In most Wasatch Front areas, 1998 was the wettest as well as the last year of the precipitation period. An increase in landslide activity began in 1997, following two to four successive years of above-normal precipitation. This study examines the relation between the 1998 landslides and the 1995-98 precipitation period (1993-98 in Spanish Fork Canyon). Accordingly, this study investigates the significance of the most recent precipitation period in relation to the historical precipitation record, and compares it with the 1980-86 period. In addition, other causes of the 1998 landsliding are explored, most importantly hillside modification related to residential development. This study also examines several issues, and their implications, related to the 1998 Wasatch Front landslides including the susceptibility to reactivation of pre-existing landslides, consideration of the state of landslide activity, and the possibility of developing landslide-movement prediction tools based on an instability threshold concept. The majority of the landslides discussed occurred near urbanized areas of the Wasatch Front and consisted of either translational or rotational earth slides in pre-existing landslide areas. The discussion and conclusions are limited to these landslides and locations. The case histories presented provide new data intended to further the understanding of landslide hazards in the Wasatch Front.

Landslide Analysis and Early Warning Systems
Landslide Analysis and Early Warning Systems

Author: Benni Thiebes

Publisher: Springer Science & Business Media

Published: 2012-01-21

Total Pages: 272

ISBN-13: 3642275265

DOWNLOAD EBOOK

Recent landslide events demonstrate the need to improve landslide forecasting and early warning capabilities in order to reduce related risks and protect human lives. In this thesis, local and regional investigations were carried out to analyse landslide characteristics in the Swabian Alb region, and to develop prototypic landslide early warning systems. In the local study area, an extensive hydrological and slope movement monitoring system was installed on a seasonally reactivated landslide body located in Lichtenstein- Unterhausen. Monitoring data was analysed to assess the influence of rainfall and snow-melt on groundwater conditions, and the initiation of slope movements. The coupled hydrology-slope stability model CHASM was applied to detect areas most prone to slope failures, and to simulate slope stability using a variety of input data. Subsequently, CHASM was refined and two web-based applications were developed: a technical early warning system to constantly simulate slope stability integrating rainfall measurements, hydrological monitoring data and weather forecasts; and a decision-support system allowing for quick calculation of stability for freely selectable slope profiles. On the regional scale, available landslide inventory data were analysed for their use in evaluation of rainfall thresholds proposed in other studies. Adequate landslide events were selected and their triggering rainfall and snow-melting conditions were compared to intensity-duration and cumulative thresholds. Based on the results, a regional landslide early warning system was developed and implemented as a webbased application. Both, the local and the regional landslide early warning systems are part of a holistic and integrative early warning chain developed by the ILEWS project, and could easily be transferred to other landslide prone areas.

Characterization and Hazard Zonation of the Meadow Creek Landslide Affecting State Route 9, Part of the Coal Hill Landslide Complex, Western Kane County, Utah
Characterization and Hazard Zonation of the Meadow Creek Landslide Affecting State Route 9, Part of the Coal Hill Landslide Complex, Western Kane County, Utah

Author: Francis X. Ashland

Publisher: Utah Geological Survey

Published: 2009-11

Total Pages: 36

ISBN-13: 1557918228

DOWNLOAD EBOOK

This CD contains a 31-page report and two accompanying plates detailing the results of geologic and geophysical investigations of the Meadow Creek landslide in western Kane County, Utah, between October 2005 and June 2007. The roughly 1.7 miles wide by 1.3 miles long Meadow Creek landslide is part of the Coal Hill landslide complex just east of Zion National Park. Recurrent movement of the Meadow Creek landslide affects State Route 9, which provides the only highway access to the east entrance to Zion National Park. This report presents the results of our investigation that includes detailed mapping of landslide features and individual historical landslides within the complex; landslide geometry, including depths from geophysical testing; a road damage inventory; movement amounts and rates from survey-grade GPS monitoring; and distress- and movement-based relative hazard zonation of State Route 9 and the Meadow Creek landslide. The results of this study provide a better understanding of the landslide and its relation to highway distress and aid in assessing the feasibility of mitigation options and predicting future damage. 29 pages + 1 plate

Characteristics, Timing, and Hazard Potential of Liquefaction-induced Landsliding in the Farmington Siding Landslide Complex, Davis County, Utah
Characteristics, Timing, and Hazard Potential of Liquefaction-induced Landsliding in the Farmington Siding Landslide Complex, Davis County, Utah

Author: Michael D. Hylland

Publisher: Utah Geological Survey

Published: 1998

Total Pages: 42

ISBN-13: 1557916225

DOWNLOAD EBOOK

The Farmington Siding landslide complex is in Davis County, Utah, about 25 kilometers north of Salt Lake City. The landslide complex covers approximately 19.5 square kilometers and is one of 13 late Pleistocene/Holocene features along the Wasatch Front mapped by previous investigators as possible liquefaction-induced lateral spreads. The Farmington Siding landslide complex is in a largely rural area, but state and interstate highways, railroads, petroleum and natural-gas pipelines, and other lifelines cross the complex. Continued population growth along the Wasatch Front increases the likelihood of urban development within and adjacent to the landslide complex. Development along the Wasatch Front has proceeded with little consideration of hazards associated with liquefaction-induced landslides. Slope-failure mechanisms, extent of internal deformation, and timing of landslide events are poorly understood, and these factors must be evaluated to enable local governments to effectively plan for development and implement hazard-reduction strategies as needed. The purpose of this study is to assess the hazard associated with future liquefaction-induced landsliding within and adjacent to the Farmington Siding landslide complex by evaluating slope-failure modes and extent of internal deformation within the complex, inferring the geologic and hydrologic conditions under which landsliding occurred, determining the timing of landsliding, and evaluating the relative likelihood of various earthquake source zones to trigger liquefaction-induced landsliding. We chose the Farmington Siding landslide complex for this study because of the distinctiveness of geomorphic features on the northern part of the complex and the presence of landslide deposits that are clearly of different ages. Furthermore, because much of the area is rural, appropriate land-use planning measures can still be implemented to protect future development.

Geologic Hazards of the Magna Quadrangle, Salt Lake County, Utah
Geologic Hazards of the Magna Quadrangle, Salt Lake County, Utah

Author: Jessica J. Castleton

Publisher: Utah Geological Survey

Published: 2011-01-20

Total Pages: 78

ISBN-13: 155791849X

DOWNLOAD EBOOK

This study contains 10 1:24,000 scale GIS based geologic hazard maps that include liquafaction, surface fault rupture, flood hazard, landslides, rock-fall, indoor radon potential, collapsible soils, expanisve soils, shallow bedrock and shallow groundwater potential. Also includes a 73 page accompanying report that describes the hazards and provides background information on data sources, the nature and distribution of hazards, and possible hazard reducation measures.