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Survey Notes is an informative, non-technical magazine on noteworthy and interesting geologic topics in Utah. It is the official Utah Geological Survey newsletter and is produced three times a year. Regular columns include the Director's Perspective, Glad You Asked, GeoSights, Teacher's Corner, Energy News, Survey News, Core Center News, and New Publications. Published as Quarterly Review (1967-1975) and Survey Notes (1976- ). Articles in this issue include: 1) Director's Perspective, by Bill Keach; 2) Mapping Geologic Hazards in and Near Bryce Canyon National Park, by Tyler Knudsen; 3) Digging Up Evidence of Past Earthquakes in Salt Lake Valley, by Adam I. Hiscock, Emily J. Kleber, Michael D. Hylland, and Greg N. McDonald; 4) Groundwater and Wetland News: In-Lieu Fee Wetland Mitigation: A Boring Name For an Exciting Idea, by Becka Downard and Diane Menuz; 5) Glad You Asked: What do Landslides, Glaciers and Faults Have to Do with the Lakes on the Wasatch Plateau?, by Lance Weaver; 6) GeoSights: Springhill Geologic Park Davis County, Utah, by Mark Milligan; and 7) Energy News: Utah Returns to Being a Net Energy Importer, by Michael D. Vanden Berg.

Survey Notes is an informative, non-technical magazine on noteworthy and interesting geologic topics in Utah. It is the official Utah Geological Survey newsletter and is produced three times a year. Regular columns include the Director's Perspective, Glad You Asked, GeoSights, Teacher's Corner, Energy News, Survey News, Core Center News, and New Publications. Published as Quarterly Review (1967-1975) and Survey Notes (1976- ). Articles in this issue include: 1) Director's Perspective, by Bill Keach; 2) Mapping Geologic Hazards in and Near Bryce Canyon National Park, by Tyler Knudsen; 3) Digging Up Evidence of Past Earthquakes in Salt Lake Valley, by Adam I. Hiscock, Emily J. Kleber, Michael D. Hylland, and Greg N. McDonald; 4) Groundwater and Wetland News: In-Lieu Fee Wetland Mitigation: A Boring Name For an Exciting Idea, by Becka Downard and Diane Menuz; 5) Glad You Asked: What do Landslides, Glaciers and Faults Have to Do with the Lakes on the Wasatch Plateau?, by Lance Weaver; 6) GeoSights: Springhill Geologic Park Davis County, Utah, by Mark Milligan; and 7) Energy News: Utah Returns to Being a Net Energy Importer, by Michael D. Vanden Berg.

As the world population increasing considerably in tandem with the growing cities, economies, and businesses, there is a need for effective and efficient public transportation. One of the fastest, and most convenient public transport is subway. However, it has become a major concern to geotechnical engineers as the development and construction of subways are held underground where faults exist. Several seismic events such as the earthquakes in Taiwan in 1999, China in 2008, and Malaysia (Sabah) in 2015 caused by fault ruptures signify the importance of this study. Although many studies have been conducted on fault ruptures, most researchers only considered a free field (a field without tunnels) and on homogeneous cohesionless soil (sand). In this study, a gigantic physical model 1000 mm in height, 3000 mm in length, and 1000 mm in width was fabricated in Geotechnical Engineering laboratory, Universiti Putra Malaysia (UPM) to evaluate the influence of various soil properties on tunnels affected by both normal and reverse faults, as well as the effects of various fault angles and tunnel depths. Three different soil cohesion have been selected, cohesionless soil , 10 kPa and 20 kPa which due to the reason that cohesionless soil has been used in most of previous studies, and other studies (in soil stability), cohesion values of less than 23 kPa has been used. Three different soil friction angles have been investigated in this study, 27°, 33° and 39°. Previous studies have showed that range of soil friction angle between 28° and 39° indicated density of up to 80%. Results revealed that increasing the soil cohesion and friction angle resulted in reducing tunnel displacements by as much as 64% and 39% respectively. Investigation on the differences and similarities between normal and reverse faults revealed that reverse faults can bring approximately 60% more tunnel displacements compared to normal faults because a normal fault released less energy than a reverse fault. Ano

As the world population increasing considerably in tandem with the growing cities, economies, and businesses, there is a need for effective and efficient public transportation. One of the fastest, and most convenient public transport is subway. However, it has become a major concern to geotechnical engineers as the development and construction of subways are held underground where faults exist. Several seismic events such as the earthquakes in Taiwan in 1999, China in 2008, and Malaysia (Sabah) in 2015 caused by fault ruptures signify the importance of this study. Although many studies have been conducted on fault ruptures, most researchers only considered a free field (a field without tunnels) and on homogeneous cohesionless soil (sand). In this study, a gigantic physical model 1000 mm in height, 3000 mm in length, and 1000 mm in width was fabricated in Geotechnical Engineering laboratory, Universiti Putra Malaysia (UPM) to evaluate the influence of various soil properties on tunnels affected by both normal and reverse faults, as well as the effects of various fault angles and tunnel depths. Three different soil cohesion have been selected, cohesionless soil , 10 kPa and 20 kPa which due to the reason that cohesionless soil has been used in most of previous studies, and other studies (in soil stability), cohesion values of less than 23 kPa has been used. Three different soil friction angles have been investigated in this study, 27°, 33° and 39°. Previous studies have showed that range of soil friction angle between 28° and 39° indicated density of up to 80%. Results revealed that increasing the soil cohesion and friction angle resulted in reducing tunnel displacements by as much as 64% and 39% respectively. Investigation on the differences and similarities between normal and reverse faults revealed that reverse faults can bring approximately 60% more tunnel displacements compared to normal faults because a normal fault released less energy than a reverse fault. Ano

Survey Notes is an informative, non-technical magazine on noteworthy and interesting geologic topics in Utah. It is the official Utah Geological Survey newsletter and is produced three times a year. Regular columns include Glad You Asked, GeoSights, Teacher's Corner, Energy News, Survey News, Core Center News, and New Publications. Published as Quarterly Review (1967-1975) and Survey Notes (1976- ). Articles in this issue include: 1) The Curious Spring Creek Road Landslide, by Ben Erickson; 2) Investigating Earthquake Hazard on the Southern Wasatch Fault Zone, by Adam I. Hiscock, Greg N. McDonald, and Michael D. Hylland; 3) Core Center News: Why a Building Full of Rocks is So Important to Utah, by Michael D. Vanden Berg; 4) Glad You Asked! What are Ice Caves?, by Jim Davis; 5) New Geochronology Database — A Wealth of Dating Information for Utah Soail and Rock, by Steve D. Bowman; 6) GeoSights: Hole-in-the-Ground, Snake Valley, Millard County, Utah, by Mark Milligan; and 7) Survey News.

Survey Notes is an informative, non-technical magazine on noteworthy and interesting geologic topics in Utah. It is the official Utah Geological Survey newsletter and is produced three times a year. Regular columns include Glad You Asked, GeoSights, Teacher's Corner, Energy News, Survey News, Core Center News, and New Publications. Published as Quarterly Review (1967-1975) and Survey Notes (1976- ). Articles in this issue include: 1) The Curious Spring Creek Road Landslide, by Ben Erickson; 2) Investigating Earthquake Hazard on the Southern Wasatch Fault Zone, by Adam I. Hiscock, Greg N. McDonald, and Michael D. Hylland; 3) Core Center News: Why a Building Full of Rocks is So Important to Utah, by Michael D. Vanden Berg; 4) Glad You Asked! What are Ice Caves?, by Jim Davis; 5) New Geochronology Database — A Wealth of Dating Information for Utah Soail and Rock, by Steve D. Bowman; 6) GeoSights: Hole-in-the-Ground, Snake Valley, Millard County, Utah, by Mark Milligan; and 7) Survey News.

Predicting ground surface motions during an earthquake event is critical for many applications, such as structure design for seismic loading, determining displacement of landslide and evaluating instability of earth retaining wall. In engineering practice, one-dimensional equivalent linear (EL) method is widely used for ground response analysis. The EL method approximates the nonlinear soil ground using an equivalent linear system. Constant soil modulus and damping properties in the linear system are determined to be compatible with the strain levels. The method only considers the situation where horizontal shear wave vertically propagates though layered soil strata. This thesis modifies the EL scheme and evaluates the bias and uncertainty associated with the one-dimensional assumption. Based on the review of the EL approach, there is a need to make the soil modulus and damping properties frequency-dependent in order to enrich the soil response to high frequency components of the input motions. However, the frequency dependent equivalent linear (FDEL) method may over-amplify the ground response to high frequencies motion. Therefore, a modified FDEL method is proposed by combining the EL scheme and the FDEL scheme through a combination factor. The modified FDEL method is implemented into a well-known program SHAKE. Several cases were conducted to benchmark the accuracy of the modified FDEL method against a fully nonlinear method. The results suggested strong motions and motions with rich portion of high frequency components would be overestimated by FDEL approach. Statistically results for different NEHRP site classes suggest that a constant combination factor 0.2 is suitable for all site classes. With the availability of large number of downhole array data in KiK-net, validation of the one-dimensional equivalent linear methods is conducted. A total of 7440 ground response cases for 100 KiK-net stations under more than 1000 earthquake events were simulated by using t

Predicting ground surface motions during an earthquake event is critical for many applications, such as structure design for seismic loading, determining displacement of landslide and evaluating instability of earth retaining wall. In engineering practice, one-dimensional equivalent linear (EL) method is widely used for ground response analysis. The EL method approximates the nonlinear soil ground using an equivalent linear system. Constant soil modulus and damping properties in the linear system are determined to be compatible with the strain levels. The method only considers the situation where horizontal shear wave vertically propagates though layered soil strata. This thesis modifies the EL scheme and evaluates the bias and uncertainty associated with the one-dimensional assumption. Based on the review of the EL approach, there is a need to make the soil modulus and damping properties frequency-dependent in order to enrich the soil response to high frequency components of the input motions. However, the frequency dependent equivalent linear (FDEL) method may over-amplify the ground response to high frequencies motion. Therefore, a modified FDEL method is proposed by combining the EL scheme and the FDEL scheme through a combination factor. The modified FDEL method is implemented into a well-known program SHAKE. Several cases were conducted to benchmark the accuracy of the modified FDEL method against a fully nonlinear method. The results suggested strong motions and motions with rich portion of high frequency components would be overestimated by FDEL approach. Statistically results for different NEHRP site classes suggest that a constant combination factor 0.2 is suitable for all site classes. With the availability of large number of downhole array data in KiK-net, validation of the one-dimensional equivalent linear methods is conducted. A total of 7440 ground response cases for 100 KiK-net stations under more than 1000 earthquake events were simulated by using t

Predicting ground surface motions during an earthquake event is critical for many applications, such as structure design for seismic loading, determining displacement of landslide and evaluating instability of earth retaining wall. In engineering practice, one-dimensional equivalent linear (EL) method is widely used for ground response analysis. The EL method approximates the nonlinear soil ground using an equivalent linear system. Constant soil modulus and damping properties in the linear system are determined to be compatible with the strain levels. The method only considers the situation where horizontal shear wave vertically propagates though layered soil strata. This thesis modifies the EL scheme and evaluates the bias and uncertainty associated with the one-dimensional assumption. Based on the review of the EL approach, there is a need to make the soil modulus and damping properties frequency-dependent in order to enrich the soil response to high frequency components of the input motions. However, the frequency dependent equivalent linear (FDEL) method may over-amplify the ground response to high frequencies motion. Therefore, a modified FDEL method is proposed by combining the EL scheme and the FDEL scheme through a combination factor. The modified FDEL method is implemented into a well-known program SHAKE. Several cases were conducted to benchmark the accuracy of the modified FDEL method against a fully nonlinear method. The results suggested strong motions and motions with rich portion of high frequency components would be overestimated by FDEL approach. Statistically results for different NEHRP site classes suggest that a constant combination factor 0.2 is suitable for all site classes. With the availability of large number of downhole array data in KiK-net, validation of the one-dimensional equivalent linear methods is conducted. A total of 7440 ground response cases for 100 KiK-net stations under more than 1000 earthquake events were simulated by using t

Survey Notes is an informative, non-technical magazine on noteworthy and interesting geologic topics in Utah. It is the official Utah Geological Survey newsletter and is produced three times a year. Regular columns include Glad You Asked, GeoSights, Teacher's Corner, Energy News, Survey News and New Publications. Published as Quarterly Review (1967-1975) and Survey Notes (1976- ). 1) Improving Our Understanding of Earthquake Hazards in Utah, by Gary E. Christenson; 2) The Mapleton "Megatrench:" Deciphering 11,000 Years of Earthquake History on the Wasatch Fault near Provo by Susan Olig, Greg McDonald, Bill Black, Chris DuRoss, and Bill Lund; 3) New Guidelines for Evaluating Surface-Fault-Rupture Hazards in Utah, by Gary E. Christenson, L. Darlene Batatian, and Craig V. Nelson; 4) Energy News: Storing Carbon Dioxide Emissions Underground — New Projects; 5) GeoSights: Sand Dunes at Little SaharaRecreation Area, by Christine Wilkerson; and 6) Glad You Asked: Have meteorites or meteorite craters been found in Utah?, by William F. Case.

Survey Notes is an informative, non-technical magazine on noteworthy and interesting geologic topics in Utah. It is the official Utah Geological Survey newsletter and is produced three times a year. Regular columns include Glad You Asked, GeoSights, Teacher's Corner, Energy News, Survey News and New Publications. Published as Quarterly Review (1967-1975) and Survey Notes (1976- ). 1) Improving Our Understanding of Earthquake Hazards in Utah, by Gary E. Christenson; 2) The Mapleton "Megatrench:" Deciphering 11,000 Years of Earthquake History on the Wasatch Fault near Provo by Susan Olig, Greg McDonald, Bill Black, Chris DuRoss, and Bill Lund; 3) New Guidelines for Evaluating Surface-Fault-Rupture Hazards in Utah, by Gary E. Christenson, L. Darlene Batatian, and Craig V. Nelson; 4) Energy News: Storing Carbon Dioxide Emissions Underground — New Projects; 5) GeoSights: Sand Dunes at Little SaharaRecreation Area, by Christine Wilkerson; and 6) Glad You Asked: Have meteorites or meteorite craters been found in Utah?, by William F. Case.