Presentation Type
Poster Presentation
Category
STEM (science, technology, engineering, mathematics)
Abstract/Artist Statement
Regional seismic stations are distributed sparsely throughout Montana. The thin dispersion of stations inhibits the evaluation of aftershock evolutions following a larger earthquake, as well as hinders the ability to record low magnitude events. To account for these limitations, a dense concentration of seismic stations from the University of Montana, Montana Bureau of Mines and Geology, and the USGS were specifically deployed around the area of the 2017 Lincoln, MT earthquake. With a magnitude of 5.8, this event was one of the largest earthquakes in Montana’s history. In years following the mainshock, a sequence of aftershocks have occurred along adjacent faults subparallel to the mainshock. I hypothesize that many of these events went unnoticed, because their magnitudes were too low for distant seismic stations to detect them. The absence of these events in current catalogs may lead to misinterpretations or incomplete interpretations of the fault mechanics, geometry, and behavior of active faults in west-central Montana, as well as conceal evidence of re-activated faults, or faults not mapped due to a lack of surficial evidence.
To accomplish this objective, the continuous seismic data that was collected by these stations will be processed through a software called QuakeMigrate (QM). QM will siphon through the recorded events, determine which events are likely to be real earthquakes, based on a series of user specified parameters, and output the approximate epicenter, depth, magnitude, and degree of uncertainty for each event. Further analysis of this data will provide input for determining the spatial and temporal patterns of aftershocks, the type of deformation associated with each event, and provide evidence that supports or refutes the current understanding of the underlying mechanics in west-central Montana.
Mentor Name
Hilary R. Martens
Microseismic Mapping of the Aftershock Sequences Following the Magnitude 5.8 Lincoln, MT Earthquake
UC North Ballroom
Regional seismic stations are distributed sparsely throughout Montana. The thin dispersion of stations inhibits the evaluation of aftershock evolutions following a larger earthquake, as well as hinders the ability to record low magnitude events. To account for these limitations, a dense concentration of seismic stations from the University of Montana, Montana Bureau of Mines and Geology, and the USGS were specifically deployed around the area of the 2017 Lincoln, MT earthquake. With a magnitude of 5.8, this event was one of the largest earthquakes in Montana’s history. In years following the mainshock, a sequence of aftershocks have occurred along adjacent faults subparallel to the mainshock. I hypothesize that many of these events went unnoticed, because their magnitudes were too low for distant seismic stations to detect them. The absence of these events in current catalogs may lead to misinterpretations or incomplete interpretations of the fault mechanics, geometry, and behavior of active faults in west-central Montana, as well as conceal evidence of re-activated faults, or faults not mapped due to a lack of surficial evidence.
To accomplish this objective, the continuous seismic data that was collected by these stations will be processed through a software called QuakeMigrate (QM). QM will siphon through the recorded events, determine which events are likely to be real earthquakes, based on a series of user specified parameters, and output the approximate epicenter, depth, magnitude, and degree of uncertainty for each event. Further analysis of this data will provide input for determining the spatial and temporal patterns of aftershocks, the type of deformation associated with each event, and provide evidence that supports or refutes the current understanding of the underlying mechanics in west-central Montana.