Emily Morton | University of Utah (original) (raw)

Papers by Emily Morton

Bulletin of the Seismological Society of America, 2014

Abstract Dynamic earthquake triggering, the process through which stresses transmitted through th... more Abstract Dynamic earthquake triggering, the process through which stresses transmitted through the passage of seismic waves can trigger remote faults to fail, has been shown to be fairly common throughout the globe and especially in seismically active areas of high heat flow and geothermal activity. We explore the possibility of dynamic earthquake triggering around the Socorro magma body, a feature within the Rio Grande rift in New Mexico that exhibits high heat flow and heightened seismicity. Because the area fits the environment type in which triggering preferentially occurs, we examine 319 global mainshocks with M w ≥6.0 for the possibility of increased seismicity rates following the passage of the mainshock waves. We examine local event locations and origin times relative to mainshock phase arrivals for patterns distinguishing triggering mainshocks from nontriggering mainshocks. We find a small triggering response during the time period analyzed, unlike following the 2002 Denali fault earthquake (DFE). This small response corresponds to smaller peak dynamic stresses than are found in other triggering studies ( M w >7.0), at a regional to small teleseismic distance (

Geological Society of America Abstracts with Programs, 2016

Geological Society of America Abstracts with Programs

Seismological Research Letters, 2021

The Nevada Seismological Laboratory (NSL) at the University of Nevada, Reno, installed eight temp... more The Nevada Seismological Laboratory (NSL) at the University of Nevada, Reno, installed eight temporary seismic stations following the 15 May 2020 Mww 6.5 Monte Cristo Range earthquake. The mainshock and resulting aftershock sequence occurred in an unpopulated and sparsely instrumented region of the Mina deflection in the central Walker Lane, approximately 55 km west of Tonopah, Nevada. The temporary stations supplement NSL’s permanent seismic network, providing azimuthal coverage and near-field recording of the aftershock sequence beginning 1–3 days after the mainshock. We expect the deployment to remain in the field until May 2021. NSL initially attempted to acquire the Monte Cristo Range deployment data in real time via cellular telemetry; however, unreliable cellular coverage forced NSL to convert to microwave telemetry within the first week of the sequence to achieve continuous real-time acquisition. Through 31 August 2020, the temporary deployment has captured near-field record...

On 15 May 2020 an MWW 6.5 earthquake occurred beneath the Monte Cristo Range in the Mina Deflecti... more On 15 May 2020 an MWW 6.5 earthquake occurred beneath the Monte Cristo Range in the Mina Deflection region of western Nevada. Rapid deployment of eight temporary seismic stations enables detailed analysis of its productive and slowly decaying aftershock sequence (p=0.8) which included ~18,000 autodetected events in 3.5 months. Double-difference, waveform-based relative relocation of 16,714 earthquakes reveals a complex network of faults, many of which cross the inferred 35-km long east-northeast-striking, left-lateral mainshock rupture. Seismicity aligns with left-lateral, right-lateral, and normal mechanism moment tensors of 128 of the largest earthquakes. The mainshock occurred near the middle of the aftershock zone at the intersection of two distinct zones of seismicity. In the western section, numerous subparallel, shallow, northRevised Manuscript Submitted to Seismological Research Letters 2 northeast-striking faults form a broad flower-structure-like fault mesh that coalesces ...

Seismological Research Letters

Seismological Research Letters, 2015

The Journal of the Acoustical Society of America, 2013

ABSTRACT In May 2013 we performed a series of seventy explosion tests, varying the mass, shape, a... more ABSTRACT In May 2013 we performed a series of seventy explosion tests, varying the mass, shape, and height of the explosives. Shots were comprised of 11.6 kg, 4.9 kg, and 1.7 kg cylinders and 14.9 kg spheres, all of Comp-B. Explosive heights varied between 4, 2, 1, and 1/2 m above the surface, at the surface, and buried 1 m below the surface. Explosives above the surface were suspended by rope between two concrete pillars. In addition, ground surfaces were altered between dry sand, chicken wire, and concrete blocks. We monitored the explosions on 13 acoustic stations. Four temporary stations were deployed surrounding the shot site at less than 1 km distance. Eight additional stations were at distances of 1 to less than 9 km, and one at ~23 km from the shot site, 4 of which were temporary stations, and 5 are part of the Los Alamos Seismo-acoustic Network. We report on a detailed analysis of signal differences related to explosive and meteorological variations. The large quantity of data from repeating shots enables us to formally characterize the relative importance of source and path variations.

Bulletin of the Seismological Society of America, 2014

Abstract Dynamic earthquake triggering, the process through which stresses transmitted through th... more Abstract Dynamic earthquake triggering, the process through which stresses transmitted through the passage of seismic waves can trigger remote faults to fail, has been shown to be fairly common throughout the globe and especially in seismically active areas of high heat flow and geothermal activity. We explore the possibility of dynamic earthquake triggering around the Socorro magma body, a feature within the Rio Grande rift in New Mexico that exhibits high heat flow and heightened seismicity. Because the area fits the environment type in which triggering preferentially occurs, we examine 319 global mainshocks with M w ≥6.0 for the possibility of increased seismicity rates following the passage of the mainshock waves. We examine local event locations and origin times relative to mainshock phase arrivals for patterns distinguishing triggering mainshocks from nontriggering mainshocks. We find a small triggering response during the time period analyzed, unlike following the 2002 Denali fault earthquake (DFE). This small response corresponds to smaller peak dynamic stresses than are found in other triggering studies ( M w >7.0), at a regional to small teleseismic distance (

Geological Society of America Abstracts with Programs, 2016

Geological Society of America Abstracts with Programs

Seismological Research Letters, 2021

The Nevada Seismological Laboratory (NSL) at the University of Nevada, Reno, installed eight temp... more The Nevada Seismological Laboratory (NSL) at the University of Nevada, Reno, installed eight temporary seismic stations following the 15 May 2020 Mww 6.5 Monte Cristo Range earthquake. The mainshock and resulting aftershock sequence occurred in an unpopulated and sparsely instrumented region of the Mina deflection in the central Walker Lane, approximately 55 km west of Tonopah, Nevada. The temporary stations supplement NSL’s permanent seismic network, providing azimuthal coverage and near-field recording of the aftershock sequence beginning 1–3 days after the mainshock. We expect the deployment to remain in the field until May 2021. NSL initially attempted to acquire the Monte Cristo Range deployment data in real time via cellular telemetry; however, unreliable cellular coverage forced NSL to convert to microwave telemetry within the first week of the sequence to achieve continuous real-time acquisition. Through 31 August 2020, the temporary deployment has captured near-field record...

On 15 May 2020 an MWW 6.5 earthquake occurred beneath the Monte Cristo Range in the Mina Deflecti... more On 15 May 2020 an MWW 6.5 earthquake occurred beneath the Monte Cristo Range in the Mina Deflection region of western Nevada. Rapid deployment of eight temporary seismic stations enables detailed analysis of its productive and slowly decaying aftershock sequence (p=0.8) which included ~18,000 autodetected events in 3.5 months. Double-difference, waveform-based relative relocation of 16,714 earthquakes reveals a complex network of faults, many of which cross the inferred 35-km long east-northeast-striking, left-lateral mainshock rupture. Seismicity aligns with left-lateral, right-lateral, and normal mechanism moment tensors of 128 of the largest earthquakes. The mainshock occurred near the middle of the aftershock zone at the intersection of two distinct zones of seismicity. In the western section, numerous subparallel, shallow, northRevised Manuscript Submitted to Seismological Research Letters 2 northeast-striking faults form a broad flower-structure-like fault mesh that coalesces ...

Seismological Research Letters

Seismological Research Letters, 2015

The Journal of the Acoustical Society of America, 2013

ABSTRACT In May 2013 we performed a series of seventy explosion tests, varying the mass, shape, a... more ABSTRACT In May 2013 we performed a series of seventy explosion tests, varying the mass, shape, and height of the explosives. Shots were comprised of 11.6 kg, 4.9 kg, and 1.7 kg cylinders and 14.9 kg spheres, all of Comp-B. Explosive heights varied between 4, 2, 1, and 1/2 m above the surface, at the surface, and buried 1 m below the surface. Explosives above the surface were suspended by rope between two concrete pillars. In addition, ground surfaces were altered between dry sand, chicken wire, and concrete blocks. We monitored the explosions on 13 acoustic stations. Four temporary stations were deployed surrounding the shot site at less than 1 km distance. Eight additional stations were at distances of 1 to less than 9 km, and one at ~23 km from the shot site, 4 of which were temporary stations, and 5 are part of the Los Alamos Seismo-acoustic Network. We report on a detailed analysis of signal differences related to explosive and meteorological variations. The large quantity of data from repeating shots enables us to formally characterize the relative importance of source and path variations.