Previously Funded Projects
QRC members lead and participate in a wide range of disciplinary and interdisciplinary research projects from the study of past earth climates and glaciations to shifts in the geographic distributions and evolution of vegetation and faunal communities, to the evolution and dispersals of the genus Homo and the increasing scales of human modification of earth environments through the Holocene. QRC provides a venue for meeting and collaborating with scholars across Quaternary disciplines. We are also fortunate to be able to provide seed funding and small grants for member research projects. We are especially happy to support grad student and junior scholar research activities, much of which leads to larger, external funding from agencies like the National Science Foundation.
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The Risk of Tsunamis to Coastal Groundwater Resources in Northern Cascadia: Reconstructing the Extent of the 1964 Alaska Tsunami Using Geologic Evidence to Determine the Potential Threat of Future Marine Inundation to Groundwater Resources in Western Vancouver Island, Canada
Abstract: The effects of tsunamis are not isolated to the destructive force of the wave alone. This is apparent in the interactions between the saline seawater of a tsunami and freshwater stored in groundwater-bearing geologic formations known as aquifers. Research suggests that tsunami-related salinization may yield groundwater undrinkable for 4 to 15 years following a tsunami. Key variables of uncertainty are tsunami inundation height, rainfall recharge rate, and the speed at which water can pass through site-specific geologic material. Thus, studying this problem is interdisciplinary and requires methodologies from both the coastal hazards and hydrogeological disciplines. In North America, the area with the highest tsunami risk is the Cascadia Subduction Zone (CSZ) – an area of tectonism from northern California to southern British Columbia. The most recent tsunami and subsequent tsunami deposit in the CSZ (a thin < 5 cm layer of sand contained within marsh sediments) is from the 1964 Alaska earthquake/tsunami which caused damage to the coastal communities of Port Alberni, Ucluelet, and Tofino, BC. I will develop a methodology seeking to answer two questions: (1) can grain size distributions of the 1964 tsunami deposit be used to reconstruct the 1964 tsunami wave height and from this data, can a map of the geographic extent of the tsunami be generated? 2. Based on (1) and considering variations in precipitation and aquifer materials, what is the vulnerability of regional groundwater to future tsunamis? I will generate a groundwater vulnerability map for the region. This will be the first map of its kind created in Canada and provide not only vital information for communities in the region seeking to protect their water supply but also act as a blueprint for future studies.Report: pending
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Reconstructing 500 years of relative sea level change in the northern section of Cascadia using a foraminiferal-Bayesian transfer function at Port Alberni, British Columbia, Canada
Abstract: The Cascadia coastline, spanning southern British Columbia to northern California, is prone to some of the greatest megathrust earthquakes (magnitude 8-9) and subsequent tsunamis. Throughout the Holocene, these earthquakes produce patterns of vertical land motion that’s recorded in salt marsh stratigraphy as relative sea-level (RSL) change caused by uplift or subsidence. Given the lack of great earthquakes since 1700 C.E., geological investigation remains the only way to assess reoccurrence intervals and intensities. Proxies including microfossils (i.e., foraminifera) have been used as a reconnaissance tool for obtaining changes in RSL because their assemblages vary strongly to tidal elevation. By using tidally sensitive foraminifera, we can capture an earthquakes full cycle (preseismic and postseismic signals) and quantify coseismic subsidence estimates. Therefore, RSL reconstructions shed light into the magnitude and habit of great Cascadia subduction zone (CSZ) earthquakes. Despite the wealth of successful geologic records documenting coseismic subsidence estimates in Cascadia, most studies have taken place in the U.S., with major knowledge gaps existing in the northern section of the CSZ in British Columbia. The aim of my research is to reconstruct the sea level history over the last ~500 years at Port Alberni, British Columbia. Resolving whether coseismic subsidence occurred at Port Alberni will allow current rupture models to be better constrained. To better understand estimation and variability of past earthquake in the northern section, I will apply a foraminiferal Bayesian transfer function (B-TF) and incorporate prior information to resolve the ongoing debate if Port Alberni subsided during the 1700 C.E. Cascadia earthquake. 48 surface sediment samples were collected at the Port Alberni salt marsh along three transects representing key elevation changes within the marsh spanning from upland to subtidal zones. Surface sediment samples will be used for micropaleontological analysis and loss-on-ignition. Three 1.5 m sediment cores were retrieved from the marsh, will be used to access the microfossil record, and establish a chronology (137Cs, 210Pb and 14C). A B-TF will be used to relate the surface foraminifera assemblages and their elevations, to their fossil assemblage, creating the first high-resolution sea level history reconstruction at Port Alberni.
It is anticipated that the results will determine better understanding of plate boundary processes whether Cascadia produces full trench or multi-segment ruptures. We can additionally prepare coastal communities into resilient ones’, by equipping them with risk assessment plans, evacuation strategies, and inundation and coastal erosion maps.
Report: pending