Postgraduate Student Presentations - Convener: Alex Nichols
Amy Dreyer, Reuben Chubb and Takashi Murachi
University of Canterbury
Time & Place
Thu, 21 Oct 2021 16:00:00 NZDT in ER 263
Join us on Zoom: https://canterbury.zoom.us/j/4408336887
Educational Role-playing Simulation For Volcanic Crisis At Taupō Volcano.
Amy Dreyer (Geology BSc Hons, GEOL470, candidate)
Educational role-playing simulations have proved successful in enhancing the learning of natural hazards. Participants improve transferable skills such as communication, teamwork, decision making, and problem solving whilst also learning content knowledge on volcanoes. The role-playing game is designed with the learning outcomes of understanding silicic volcanism, understanding associated probabilities of eruption, and understanding the role of Iwi within crisis management. The simulation discussed here is situated at Taupō Caldera, a silicic volcano that has produced destructive explosive eruptions and undergone extensive periods of volcanic unrest without eruption. Any future eruption, or even period of sustained and/or severe volcanic unrest, could have considerable societal impacts locally and across New Zealand.
This research project has produced two simplified scenarios in line with ECLIPSE framework scenarios for Taupō Volcano (Campbell 2020), based on historic behavior of Taupō volcano, analogous global silicic eruptions, and an expert elicitation exercise (Scott 2021). One scenario describes volcanic unrest leading to an eruption, and the other presents a scenario of volcanic unrest leading to emplacement of magma without eruption. Volcanic unrest activity includes increased seismicity, low frequency earthquakes, and migration of earthquake hypocenters, ground deformation, increased geothermal activity, hydrothermal eruptions, and development of new fumaroles. The eruption sequence includes dome formation followed by a Plinian phreatomagmatic eruption.
The educational role-playing simulation is designed for, but not limited to, students entering the industry. Participants are divided into groups and assigned roles that reflect a simplified version of New Zealand’s key stakeholder team structures: Geonet, Civil Defense Emergency Management, and Iwi (Campbell 2020). The game runs for 5 hours and simulated data reporting on the behavior of the volcano and the community is streamed to participants. The participants work together with the goal of successfully monitoring and managing the volcanic crisis.
Campbell G. 2020. Hazard and Impact Scenario Development for Silicic Volcanoes in New Zealand [MSc thesis, University of Canterbury]. UC Research Repository. http://dx.doi.org/10.26021/7590
Scott E. 2021. Development of a Bayesian Event Tree for Short-term Eruption Onset Forecasting at Taupō Volcano [Unpublished MSc thesis, University of Canterbury].
Structural Analysis of The Humps Fault and Surrounding Bedrock Geology, Waiau, North Canterbury
Reuben Chubb (Geology BSc Hons, GEOL470, candidate)
Surface rupturing displacements from the 7.8 Kaikoura Earthquake were traceable for 36km along The Humps Fault. Limited detailed geological mapping had been conducted for The Humps Fault and its surrounding bedrock. The primary objectives of this report were to 1) describe the geometries and relative timing relationships between The Humps Fault and eastern edge of the Emu Plains (EEEP) structures 2) determine whether the Kaikoura Earthquake rupture pattern was typical for the area. These objectives were achieved by creating a comprehensive bedrock map and series of cross-sections for the area where The Humps Fault intersects EEEP structures.
The Humps Fault crosses the Emu Plains striking at ~90° and dipping steeply to the south (Humps West), it changes orientation after the intersection with the Mt Highfield Fault, striking ~60° and dipping steeply to the northwest (Humps East). There are two prominent structural folds associated with the Mt Highfield Fault, the Mt Highfield Anticline and Chaffey Syncline. The Humps Fault West is expressed through three parallel surface strands with a cumulative bedrock offset (CBO) across the fault zone of 4100m 1000m. All three segments demonstrate right lateral movement and dissect the Mt Highfield structures.
Average single event displacements (SED) from 2016 increase from 1.1m on the Humps West to 2.6m on the Humps East. Strain from the abutting Mt Highfield Fault is being partitioned onto The Humps Fault causing an increase in displacement. East of the intersection the Humps strands are accommodating a component of shortening which is expressed by its change in orientation. North Canterbury Domain faults that ruptured in 2016 follow a power-law relationship where SED = 0.041 CBO 0.47. The relationship suggests that the 2016 Earthquake can be interpreted as consistent with the long-term deformation history where faults that have produced large CBO also have larger SED.
Magnetic Gradiometer Measurements of Disturbed Braided River Sediments at Oxford Cemetery, North Canterbury
Takashi Murachi (Professional and Community Engagement Internship, PACE495 candidate)
The geologically young Canterbury Plains are one of unique sediment linked to braided rivers among the selected countries, Canada, Italy, USA (Alaska). It is essential to study the historical and social background factors that are associated with land use change by natural disasters and human activities for survey set-up. The first recorded grave at Oxford Cemetery is from the 9th of October 1874 and the historical records of the cemetery are significant in determining the anomaly object size, type of burial in a way of spatial resolution, line spaces setting and feature object. The Magnetic Gradiometer has never been used at a fluvial sedimentary site. Working with Southern Geophysical Ltd. (SGL), they have confirmed the effectiveness of both GPR and Magnetic Gradiometer at a site consisting of sand, a homogeneous subsurface, in New Zealand and obtained a GPR result at Oxford Cemetery. SGL has been seeking whether a Magnetic Gradiometer can effectively detect a disturbed area of magnetic soils in a complex sedimentary subsurface from braided river remains to determine the location of unmarked graves at Oxford Cemetery. The aim of the project is to evaluate the usefulness of a high-resolution magnetic fluxgate gradiometer, called Grad601-2 in a fluvial braided river sedimentary environment. Then, by comparison of the Magnetic Gradiometer and a previously completed Ground Penetrating Radar (GPR) survey by a local geophysics company, Southern Geophysical Ltd., at Oxford Cemetery, determine whether a Magnetic Gradiometer is a useful instrument for determining the location of unmarked graves.