Submission Type
Poster
Start Date
4-26-2021
Abstract
Pine Valley Mountain in the southwestern corner of Utah is the site of a laccolith, the cooled remnants of an inflating magma chamber in between two layers of pre-existing rock. Magma chamber inflation can cause a dome like uplift in the D10 overlying rock units leading to oversteepening of the slope, triggering landslides and volcanic eruptions, like the Mt. St. Helens eruption in 1980. Through paleomagnetic analysis we can determine the timescale over which the emplacement occurred by observing how much wander the Earth’s magnetic pole experienced as the sheets of magma were emplaced and cooled. If results show a small amount of wander in the Earth’s magnetic pole, that will indicate a very rapid (in the context of geologic time) emplacement which could result in a catastrophic landslide-triggered volcanic eruption. If the magnetic pole experiences a large amount of wander, that suggests a slower rate of emplacement and contradict a landslide-triggered eruption event.
Recommended Citation
Polizzi, Emily, "058— Thermal demagnetization constraints on the rate of emplacement of the Pine Valley Mountain Laccolith, Utah" (2021). GREAT Day Posters. 35.
https://knightscholar.geneseo.edu/great-day-symposium/great-day-2021/posters-2021/35
058— Thermal demagnetization constraints on the rate of emplacement of the Pine Valley Mountain Laccolith, Utah
Pine Valley Mountain in the southwestern corner of Utah is the site of a laccolith, the cooled remnants of an inflating magma chamber in between two layers of pre-existing rock. Magma chamber inflation can cause a dome like uplift in the D10 overlying rock units leading to oversteepening of the slope, triggering landslides and volcanic eruptions, like the Mt. St. Helens eruption in 1980. Through paleomagnetic analysis we can determine the timescale over which the emplacement occurred by observing how much wander the Earth’s magnetic pole experienced as the sheets of magma were emplaced and cooled. If results show a small amount of wander in the Earth’s magnetic pole, that will indicate a very rapid (in the context of geologic time) emplacement which could result in a catastrophic landslide-triggered volcanic eruption. If the magnetic pole experiences a large amount of wander, that suggests a slower rate of emplacement and contradict a landslide-triggered eruption event.
Comments
Sponsored by Scott Giorgis. This project was made possible by the assistance of David Hacker from Kent State University. David Hacker kindly helped us plan our field season 2018 and helped us understand the geology of the area. Field work was conducted by Rebecca Richards, Tim Williams, and Scott Giorgis with logistical assistance from Gary, Susan, and David Giorgis. Discussions with Eric Horseman (Eastern Carolina University) improved our understanding the process of laccolith emplacement. The thermal demagnetization oven used in this study was donated by the University of Florida with the assistance of Joseph Meert. Stephen Tulowiecki aided in the creation of maps for figures. This research was funded by the donors to the Geology Fund of the Geneseo Foundation. Scott Giorgis was the advisor for this honors thesis.