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.
Dating Puget Landslides and Sediment Deposits
On the western Whidbey Island shoreline, there is a 3 km-long ancient landslide complex with evidence of episodic mass wasting. The bluff morphology within the ancient landslide complex is that of hummocky terrain buttressing 10 – 20 m-high scarps, and outside of the greater landslide complex there are oversteepened bluffs with only one example of a deep-seated landslide. There are lithologic contacts creating geologic conditions favorable to different hillslope processes based on the underlying sedimentology, for example: dry ravel of gravel and sand, skin slides of loose soil on till, deep-seated landslides rotating over failure planes of clay, etc. In order to locate and classify landslide geohazards, it is necessary to conduct detailed mapping of the substrata. However, correlation of units is difficult without quantitative age control on the units, furthermore there is little quantitative age constraint on the history of landsliding on western Whidbey Island. For this study, we will report on the results of C-14 (and potentially OSL) dates gathered, and apply their contribution to previous dating work in the area. The results will add context to the glacial and landslide history in the region, which subsequently facilitates the detailed mapping of the stratigraphy. Detailed mapping of the stratigraphy will help us locate landslide-prone regions.
Holocene history of neotectonics, earthquakes, tsunamis, volcanism, paleoclimate and people on Kamchatka – visit of Vera Ponomareva
This grant funded the travel of Vera Ponomareva, Senior Researcher, Institute of Volcanology and Seismology, to visit colleagues at UW and QRC, particularly Jody Bourgeois. Vera and Jody have been working together, primarily on Kamchatka, since 1999 (representative references below), with their most recent collaboration focused on the mid-Holocene history of people and processes in the region near Ust’ Kamchatsk (central-east Kamchatka). In 2010, we excavated a peat near Krutoberegovo (the end of the road on Kamchatka!), which recorded the full Holocene record. With excavation and coring, we sampled 7 m of peat for pollen studies (Florin Pendea, Lakehead University, Ontario) and tephra stratigraphy (Vera Ponomareva), with reference to coastal sections recording earthquakes and tsunamis (Jody Bourgeois and students), and to archaeological sites recording mid- to late Holocene occupation (University of Buffalo group). The purpose of Dr. Ponomareva’s visit in 2015 is to work more fully on the tephra record from this peat and related sites. Jody will benefit from Vera’s expertise in reconstructing the history of various sites she and her students have worked on. Vera will present at least one QRC talk on her tephra work, later in the spring.
Rates and mechanisms of bedrock incision and strath terrace formation in a forested catchment, West Fork Teanaway River, Cascade Range, Washington
Rivers incise bedrock, setting the tempo for landscape development, through periods of incision and incisional hiatuses. While many theoretical and experimental efforts have sought to understand the controls on bedrock incision and the evolution of bedrock channel shape, questions regarding the processes and controls on vertical and lateral bedrock erosion are informed by relatively few direct field measurements. To better understand rates, controls, and mechanisms of lateral and vertical bedrock incision by rivers, we measured bedrock bed and bank incision and mapped and radiocarbon-dated strath terraces in the West Fork Teanaway River. The West Fork drains 102 km2 of the tectonically quiescent southeastern North Cascade Range of Washington, and, in its lower 3 river kilometers, is rapidly incising its bed and creating strath terraces.
Land use, erosion, and sediment storage over the last two millennia in a mountainous catchment in southwest Sichuan Province
The requested funding will partially support 2015 field work and AMS dates for a field study of land use, soil erosion, and sediment budgets in the upper Baiwu Valley, a small, forested watershed in a mountainous, ethnic minority area of southwest Sichuan Province, China. The project builds on ethnographic and forest ecology research in the area by Steven Harrell (UW Anthropology) and Thomas Hinckley (UW SEFS). The study has three broad objectives: (1) To unravel the environmental history of the watershed and its human occupants—how changing patterns of land use, soil erosion, and fluvial processes have interacted through time. (2) To investigate the sustainability of soil under traditional swidden systems (practiced in the basin from about 1750 to 1950 by members of the Nuosu ethnic group, also the watershed’s current inhabitants) and, more broadly, traditional local knowledge. (3) To characterize the role of sediment storage in a small Yangtze River headwaters basin, over the last two millennia, in modulating the link between natural and anthropogenic erosion and downstream sedimentation. The project consists of field mapping and surveying valley fill; using OSL, 137Cs, 210Pb, and 14C to age valley sediments; mapping soil-profile truncation to assess the extent and intensity of erosion; and using ethnographic data and satellite imagery to understand historical land use practices and patterns.
The Future of the Past: Capturing a 5000 year record of Human‐>Environmental variability on the North Coast of Alaska
QRC funds provide travel support to take a small group of UW graduate students to Barrow, Alaska in July 2016 to participate in a rescue excavation of the Walakpa archaeological site. This project will support the strategic sampling of a repository of archaeological and environmental information spanning the past 3500‐5000 years at a location of critical importance for understanding the cultural change and movements of Arctic people through late Holocene. The work will preserve vital data and give UW students potential future research projects. The site is full of well‐preserved organic artifacts (marine and land hunting implements, boat and sled parts, food processing and clothes making tools, clothing, baskets, toys, jewelry), house foundations, and burials that the Inupiat community of Barrow wants moved to safer ground. The site includes paleo-environmental data on changes in marine and terrestrial ecology, sea ice history and polar climate from the mid to late Holocene, but the site is highly vulnerable to erosion and may not last another warm winter. The site has the potential to reveal new insights about the development of Arctic maritime adaptations, human responses to climate changes, the causes of both the pre-Dorset and Thule (ancestral Inuit) migrations from Alaska across the Eastern High Arctic (ca 2200 B.C. and 1200 A.D., respectively).
For the QRC and UW, this rescue operation presents a unique opportunity to further the Arctic legacy that was initiated by QRC founders Linc Washburn, Steve Porter, and others and that manifests today in the QRC engagement in the Future of Ice Initiative. Perhaps most importantly, the chance to introduce a new generation of students to the Arctic at a site that will generate significant research opportunities is especially valuable when Arctic researchers are few and the Arctic is losing archaeological sites at an unprecedented rate.
A Trace Element Laboratory for Environmental Science
Instrumentation for a state of the art mass spectrometry facility at the University of Washington for the analysis of trace elements in natural materials: to track animal migration, uncover the geological and biological processes that shape our planet, reconstruct past climate, and trace contaminants in the environment.
Cascadia subduction zone tsunamis and land-level change in Puget Sound, Washington
My research seeks to determine where Cascadia tsunamis been recorded in Puget Sound tidal marshes; and what environmental changes, if any, occurred in these tidal marshes in response to coseismic and/or postseismic deformation from great earthquakes on the Cascadia Subduction Zone.
The extent that Cascadia earthquakes and tsunamis affect Puget Sound is relatively unknown. I will use diatom paleoecology and sedimentology to study two types of evidence. First, I will identify tsunami deposits preserved in Puget Sound tidal marshes. Second, I will determine whether or not Puget Sound tidal marshes record land-level change that coincided with, or shortly followed, great Cascadia earthquakes.
Evaluation of paleoflood evidence, Matanuska Valley, Alaska
There are two interpretations of the surficial geological evidence in the lower reaches of the Matanuska River in Alaska: the last significant event was the retreat of the Matanuska Glacier (“glacier only” model) or the retreat was followed by a megaflood that reshaped the landscape (“flood” model). The purpose of this proposal is to resolve this conflict.
We intend to (1) map geomorphic features in the contentious areas of the Matanuska and Knik valleys with newly available high-resolution LiDAR DEMs; (2) to conduct fieldwork to assess stratigraphy and lithology of geomorphic features; (3) to model hydrologic processes of various flood flows down the Matanuska Valley.
We will test the following 3 hypotheses: (1) the discrepancy between the “glacier only” and “flood” models can be resolved if the Knik Glacier readvanced over the previously flooded Matanuska lowlands, leaving the glacial features in the path of the earlier Atna flood, or (2) some areas of glacial ice survived the Atna flood, shielding glacial landforms from erosion by the floodwaters; and (3) the glacier dam at Tahneta Pass was destroyed nearly instantaneously. H3 is an interesting problem reaching well beyond the Atna floods (cf. Batbaatar and Gillespie, 2015) and we intend to test it by quantifying discrepancies between flood depths inferred from geological evidence and from hydrologic modeling.
This proposal will build on work previously published in Quaternary Research. The existence of Glacial Lake Atna has been recognized for well over a century (Schrader, 1900), but other than our previous paper, no reports have discussed in detail the lake’s relation to four large adjacent drainages (Matanuska, Susitna, Tanana/Yukon, and Copper rivers) or the modes in which this very large ice impounded lake drained. The project area is one we know very well, and by Alaska standards is highly accessible and has many sites with existing exposures (e.g., gravel pits, road cuts)—so our ability to accomplish necessary field tasks is greatly enhanced.
Preserving the Past Together: A Seminar in Cultural and Environmental Heritage Management
This year long seminar will bring together archaeologists at the University of Washington with a diverse group of heritage professionals outside of academia. Seminar participants will discuss the current challenges and future possibilities for developing inclusive approaches to heritage management that integrate the needs of multiple stewards and stakeholders within the Pacific Northwest. Organized as a series of public lectures with discussion panels, workshops and a capstone conference, the seminar will include participants and representatives from tribal governments, local, federal, and state institutions and agencies, and professionals employed within private cultural resource management (CRM) firms. Our objectives are to build new networks of knowledge sharing among these diverse stewards and stakeholders that will result in a series of pilot community-based partnerships that address critical needs associated with preserving and protecting history and heritage within our region. From these dialogues and projects we will create an archive of best practices and guidelines for community-based approaches to archaeological practice and heritage management.
The University of Washington is uniquely positioned to host and facilitate this dialogue. Combined with the campus’ ongoing commitment to strengthening its relationship with local tribal nations and campus initiatives designed to retain and train Native American and other indigenous descendent students, UW faculty in Anthropology, History, and AIS are currently engaged in a number of community-based heritage partnerships with tribal nations in Washington and Oregon. This seminar will draw upon these strengths, using them to provide national leadership in this critical aspect of heritage management and archaeological practice.
Assisted Migration and the Future of Great Basin pikas (Ochotona princeps)
Since the end of the Pleistocene, warming climates have seen acceptable habitat for pikas (Ochotona princeps) move upslope by approximately 785 m in the Great Basin. As a result, the future of these iconic mammals in arid western North America is a matter of great concern to conservation biologists. Given that an attempt to place pikas on the federally endangered list failed, it seems extremely likely that these animals will now be the focus of proposals for what has come to be known as “Assisted Migration”—the purposeful movement of animals across space to establish new, and hopefully successful, populations of those animals. The work to be conducted under this grant brings together three individuals to address issues related to pika assisted migration. Those individuals are myself, with expertise in the history of small mammals in arid western North America, including pikas, and two of the world’s experts on these animals, Dr. Constance Millar (USFS Research Scientist) and Dr. Andrew Smith (Professor, Arizona State University). The work will: 1) include an examination of current occupied pika habitats in the western Great Basin, and, 2) begin the process of producing a position paper dealing with pika assisted migration for a major biological/conservation biological journal.
Bernard used QRC funds to support the presentation of the data to an audience that includes the most active groups studying mountain permafrost in diverse sites worldwide, including the Himalaya. Presenting these rich results to an informed, international audience will help us obtain external funding to sustain the collective research by my group and UW colleagues in the Himalaya. Bernard submitted an abstract titled “The diverse important roles of permafrost and periglacial processes in shaping the highest mountains on earth (ABS794)” to the 7th Canadian Permafrost Conference. The abstract was accepted and with the support of the QRC, Bernard was able to attend the conference as the NSF funds that fueled this work.
Constraining past Antarctic Ice Sheet thickness using cosmogenic 14C in bedrock
During the last glaciation, a grounded ice sheet filled the Ross Sea of Antarctica, where the Ross Ice Shelf exists today. This ice sheet began to thin around 13 kyr BP, and the transition from grounded to floating ice retreated inland towards its present position. We have mapped and dated glacial deposits alongside Darwin and Hatherton Glaciers, which record this thinning. Our new exposure ages suggest that the ice sheet remained grounded here until <3 kyr BP, which changes our understanding past ice flow in this region. Unfortunately, there was no clear limit of deposition at the mouth of Darwin Glacier, so we were not able to determine the thickness of the ice sheet at this location. We therefore will use cosmogenic 14C in a bedrock elevation transect from the mouth of Darwin Glacier, adjacent to the former Ross Sea Ice Sheet, in order to constrain the ice thickness during the last deglaciation. Due to the short half-life of this isotope, the concentration of 14C in rock reaches saturation within 30 kyr. Burial by ice would shield the rock from cosmic rays, shutting down the production of 14C. Even just a few thousand years of past ice cover will drastically reduce the concentration. Thus, if a given rock is saturated with respect to 14C, it could not have been covered by ice for any considerable amount of time in the last 30 kyr. If a rock contains less than the saturation concentration of 14C, then this suggests it was buried by ice during the last glaciation. Therefore, the respective elevations of the highest unsaturated sample and the lowest saturated sample will constrain the former ice sheet surface. We will use these data along with our chronology from nearby glacial deposits as constraints on a numerical ice-flow model in order to investigate the time at which the ice sheet began to thin at the mouth of Darwin Glacier.
Acquisition of compound-specific isotope ratio mass spectrometry capabilities in support of environmental science research
These funds will contribute to the acquisition of instrumentation to perform stable isotope analyses of individual chemical compounds from a wide variety of environmental samples. Compound-specific isotope analysis (CSIA) of carbon and nitrogen is the state-of-the-art across multiple disciplines within environmental science including ecology, biogeochemistry, oceanography, and global change. These capabilities are not currently available to environmental science researchers at the University of Washington (UW). Project PIs are Gordon Holtgrieve (SAFS), Julian Sachs (Ocean) and Paul Quay (Ocean). Project participants span six Schools and Departments within two Colleges (College of the Environment or College of Engineering), providing the critical mass, interest, and grant activity to establish environmentally related CSIA analyses on the UW campus. Adding CSIA to the existing suite of isotope measurement techniques and expertise at the UW will advance existing research programs and create new avenues for environmental research.
Paleoenvironmental constraints from paleosol-loess sequences: evaluating clumped (∆47) isotopic records in biogenic and pedogenic carbonate
The goal of the proposed work is to advance understanding of how the geochemistry of biogenic and pedogenic (formed in soil) carbonates record surface environmental temperatures and soil water compositions relevant to the interpretation of proxy records in Quaternary loess-paleosol sequences and cultural layers. Reconstructing Quaternary paleoenvironments is important for a broad range of paleoclimate, geology, biology, anthropology and archaeology studies. To this end, the geochemistry of carbonate minerals formed at and near the Earth surface can provide quantitative environmental constraints including the δ18O values of water, δ13C-based information about vegetation, and most recently, estimates of Earth-surface temperatures from clumped isotope (∆47) thermometry. Early efforts to develop clumped isotope thermometry in modern-Holocene soils raise many questions about how to interpret not only ∆47 temperatures but also conventional δ18O and δ13C values in soil and loess carbonates. Specific issues include seasonal bias in carbonate growth and vital effects in biogenic carbonate. We must address these issues in order to understand and exploit these valuable archives of environmental information preserved in paleosols and cultural layers.
The project will benefit Quaternary research by refining and developing new methods for reconstructing terrestrial Quaternary climate change from loess-paleosol sequences and environmental context from cultural layers, and benefit the intellectual life of the QRC through enhanced international visibility and exchange, support of facilities and research that benefit QRC members, and training of future Quaternary scientists.
High latitude terrestrial climate and ecology during peak greenhouse warming
This project supports field and laboratory work to enable an interdisciplinary investigation of gradients in temperature, hydrologic conditions, and vegetation across North American mid- to high-latitudes during the early Eocene global warming event (~52–50 Ma). The primary goal of this project is to advance the understanding of carbon cycling, climate dynamics, and terrestrial ecological responses to high atmospheric pCO2. By improving high latitude proxy records of climate and ecology in the deep past, this work can improve our understanding of climate feedbacks and their biological impacts during the glacial-interglacial cycles of the Quaternary as well as potential future climate states involving extremely warm or “greenhouse” conditions. This is particularly crucial as the planet has begun exhibiting unexpectedly rapid rates of change recently that may be related to high-latitude climate conditions and feedbacks.
Glaciers in Central Asia present an excellent opportunity to test glacier sensitivity to various climate settings. During the global last glacial maximum, around 20,000 years ago, glaciers in southern Siberia and Altay mountains hosted large glacier-dams to originate some of the largest outburst floods on Earth. Central Mongolia shows a similar pattern of glacier advances, in addition to slightly bigger glaciers ~30,000 years ago. In contrast, Bataa discovered that hyper-arid Gobi glaciated during the warmest period of the early-middle Holocene, with no evidence of glaciations during the coldest of the last ice age. In that condition sunlight provides sufficient energy to evaporate the ice from these precipitation-starved glaciers. This phenomenon was first observed in dry parts of the Kyrgyz Tien Shan, and now similar ‘peculiarity’ in the high roofs of Tibet have been discovered. This project aimed to constrain the chronology of glaciers in key locations, and compile a map of paleo-glaciers with different sensitivities.
Preserving human-environment relationships: Nineteenth Century food practices on the Grand Ronde Reservation
For millennia, the subsistence strategies and settlement patterns of western Oregon Native communities relied on interconnected biotic, aquatic, and social systems. Euro-American settlement in the region during the nineteenth century strained these links. Introduced diseases led to declines in the Native population while Euro-American crops and livestock and the cessation of Native landscape management altered regional ecology. In the 1850s, removal of over 30 western Oregon bands and tribes to the Grand Ronde Reservation segregated Native groups from long-important resources and ecosystems. The reservation community also grappled with numerous government attempts to terminate pre-reservation lifeways. Historical and ethnographic research suggests that despite these challenges, those at Grand Ronde continued to harvest traditional foods on the reservation and further afield. This work provides few specifics, however, on reservation diet composition, including the relative consumption of Euro-American and traditional foods. Furthermore, little archaeological research has focused on nineteenth century Native communities, at Grand Ronde and throughout the Pacific Northwest. The lack of material evidence from this period limits our understanding of the ecological, political, and social changes occurring in the region and the ways Native communities responded to them. In collaboration with the Confederated Tribes of Grand Ronde Tribal Historic Preservation Office and the Field Methods in Indigenous Archaeology field school, this project uses archaeological survey and excavation to investigate a nineteenth century reservation settlement. Fieldwork will concentrate on identification of cultural deposits containing remains of consumed plants and animals. Zooarchaeological and macrobotanical analysis will identify reservation food taxa and differences in food preparation and consumption across the site. These data will provide insight into reservation daily life, the shifting ecological and economic systems of nineteenth century western Oregon, and the strategies employed by Native groups to maintain connections to their cultural landscapes.
Frequency of Long Runout Landslides near Oso, WA and the Implications for Landscape Evolution and Natural Hazards
Slope failures like the Oso Landslide are extremely mobile and therefore pose significant risk to communities. Although it has been suggested that this slide exhibits an atypically low height: length ratio, analysis of LiDAR bare-earth imagery of the North Fork Stillaguamish (NFS) river valley near the Oso landslide suggests there are over a dozen local landslide deposits, many with strikingly similar long runout behavior. My research goal is to better understand the relationship between fluvial and mass wasting processes that drive short-term hillslope failures and longer-term landscape evolution along the NFS river valley. I aim to develop a conceptual model for this complex geomorphic system of river incision and large landslides in weakly consolidated glacial sediment. Specifically, this model will describe the following: an accurate landslide recurrence interval, including how patterns in landslide frequency have changed since the Last Glacial Maximum (critical for assessing hazard), how river erosion drives slope instability, what effects landslide events have on river channel location, whether historic seismic events relate to landslide triggering, and what the cumulative landscape response is through time. I aim to answer these questions through a combination of field mapping, GIS analysis, and radiometric carbon dating from organic debris within and directly overlying landslide deposits.
Climate Change and the Historical Record: Engaging Area Studies in the Large Research University
In this project, Peter explored climate change in the historical record and the ethics of international research by bringing together five sets of UW actors: faculty and graduate students in Southeast Asian and Latin American area studies, the UW Science Studies Network (SSNet), the Ida B. Wells School for Social Justice (IBW), the Burke Museum, and other scholars from climate sciences and policy studies outside the College of Arts and Sciences. Their aim is to broaden the audience for traditional area studies; open up a conversation on ethics in international scientific collaboration; and explore new possibilities for intellectual engagement between the natural sciences and area studies. Project activities will include a series of lunchtime workshops we are calling collaborators; a set of public lectures at the Burke Museum; the creation of new course materials; and an applied experiment in research collaboration involving faculty and graduate students from Archaeology and Oceanography that will take place in Seram, Indonesia. We have chosen a focus on the Pacific Rim emphasizing Southeast Asia, Oceania, and Latin America and concentrating on the work of scholars of Indonesia and the Philippines, the Marshall Islands, Peru, Mexico, and Canada.
C14 dating of mangrove peat cores from Seram and Ujir Islands, Indonesia
We are requesting $2,000 to obtain radiocarbon dating of mangrove peat cores collected on a recent field trip by Peter Lape to Eastern Indonesia (Seram and Ujir Islands). This collaborative fieldwork was supported by grants to Lape from National Geographic and Mellon, with matching funds of $2000 from the QRC. These funds supported fieldwork but only minimal post fieldwork analyses. The mangrove cores were collected for analysis by the Sachs lab for paleorainfall signatures. This data will be useful for both archaeological and paleoclimate research. It will allow Lape to better understand agricultural conditions for people living in Eastern Indonesia, a central question of his archaeological research. It will allow Sachs to better understand how local rainfall in Eastern Indonesia, a crucial region in the western Pacific that is influenced by monsoon systems, is linked to regional and global scale climate fluctuations.
UArctic Student Forum and Congress 2016, St. Petersburg, Russia
As part of the Future of Ice (FOI) Initiative, the University of Washington, Seattle (UW) is one of the few universities in the U.S. that are part of the University of the Arctic (UArctic), a coalition of institutions of higher education which aim to raise awareness of Arctic issues and promote Arctic-related opportunities, which among many others include internships, conferences and youth programs, to anyone around the world who has an active interests in the Arctic. In 2014 I was appointed part of the inaugural group of UArctic Student Ambassadors and represented both the UW and the U.S. The first event I attended as a UArctic Student Ambassador was in January last year when I went to Norway for the Arctic Frontiers Conference. During the conference, the student ambassadors had multiple opportunities to share their opinions on various Arctic issues as well as have special windows to chat with various luminaries in the Arctic world.
The goals I have in mind for attending the UArctic Student Forum and Congress 2016 is to gain valuable experience through a highly unique opportunity to both take the lead to and learn what it means to voice your opinions about key Arctic issues. Whether it be a scientific, humanities or social perspective(s), the growing/learning experience will be universal. As mentioned above, attendance at such conferences also serve as a major networking opportunity for me, which when considering my future goals of immersing myself in the fields of Glaciology, will definitely prove valuable to me wherever I go in life.
Large wood debris and logjam dynamics during and after the Elwha River Restoration project
Woody debris is a primary control on river morphodynamics, affecting sediment transport, streambed morphology, fluid flow and physical habitat. Dam removals have become an increasingly used tool in river management for restoring ecosystem function and natural river processes. The Elwha River Restoration project dam removals are a unique opportunity to investigate the effects of increased wood and sediment supply on woody debris dynamics and streambed morphology. Developing a quantitative understanding of how wood interacts with water and sediment to influence geomorphology and aquatic habitat remains a key challenge for river management, environmental engineering, ecology and geoscience in forested regions. Despite advances in the understanding of wood in rivers, fundamental questions remain about wood mobility, logjam dynamics and geomorphology, and their response to changes in wood, water and sediment supply. This research investigates the effects of the Elwha River Restoration project dam removals on woody debris dynamics and streambed morphology.
Radiometric Dating of Lake Sediment Cores from the South Pacific Convergence Zone for Late Holocene Paleoclimatology
The South Pacific Convergence Zone (SPCZ) is the Southern Hemisphere’s most prominent rain feature, however a full understanding of its structure and behavior is lacking, predictions of how it might respond to future warming are uncertain, and few studies have addressed its behavior in the past. Tropical atmospheric circulation is a major driver of Earth’s climate yet little is known about the extent of natural variability during the late Holocene including the Medieval Warm Period (MWP) (950-1250 AD) and the Little Ice Age (LIA) (1400-1800 AD). Organic geochemistry is a promising tool for improving our understanding of the SPCZ. To determine past variations we use hydrogen isotope ratios (2H/1H) of specific lipids from lake sediments collected in 4 target regions of the SPCZ with different average modern rainfall rates (including the Solomon Islands, Vanuatu, Wallis, and Fiji). Lipid 2H/1H measurements can reveal past change because environmental water 2H/1H is linked to fluxes of water though the hydrologic cycle and lipid 2H/1H is almost perfectly correlated with source water 2H/1H. Since growth rate, growth stage, salinity, and irradiance can influence lipid 2H/1H fractionation, duplicate records from unique freshwater lakes in each distinct region of the SPCZ will be developed. However, it is crucial to continue to develop age models for these sediment cores in order to properly interpret the climate records we generate. The objective of this project is to improve preliminary age models of several sediment cores from the SPCZ region. Completely dating (with 6-10 14C and 6-10 210Pb samples for a profile) cores that currently have sound preliminary age models is our priority. Developing age models for currently undated cores will be pursued as needed from the most promising sites to ensure duplicate records from each target region are completed. Generating records from 2 unique lakes from each of the 4 regions is the best way to ensure our interpretation of the climate signal is not influenced by local parameters (i.e. growth and light). Due to high accumulation rates in many of the SPCZ lake sites, age models based solely on 14C dates are not appropriate for many our cores, which have a significant amount of sediment that accumulated after 1900 AD. Therefore, in addition to using 14C dates, sediment chronologies will be augmented by modeling the decay profiles of unsupported lead-210 (210Pb) in the upper ~20-100 cm of sediment. Typically lipid 2H/1H analysis can yield qualitative information about wetter versus drier periods. Once strong age models are obtained and compound specific 2H/1H measurements are complete, this project will result in the 1st quantitative late Holocene hydroclimate reconstructions from this understudied region of the maritime tropics. In order to generate quantitative records of rainfall rates in the SPCZ region we have analyzed surface sediment samples from 18 lakes in 13 locations and found that the isotopic composition of the biomarker dinosterol is well correlated with modern rainfall rate. Generating records from multiple distinct sites in and around the SPCZ will allow us to characterize how this major precipitation feature changed in the past.
Climate and Culture in the Tropical Pacific during the mid-late Holocene
In the tropics paleoclimate records are discontinuous and sparse. Furthermore they are developed from diverse archives with a wide range of specialized methods such as deep sea sediment foraminifera isotope records (Koutavas and Joanides, 2012; Koutavas et al., 2006; Rustic et al., 2015), coral isotope records (DeLong et al., 2012; Linsley et al., 2006), coral elemental composition (Thompson et al., 2015), speleothem isotope records (Maupin et al., 2014; Partin et al., 2013), and lake sediment algal lipid isotope records (Atwood and Sachs, 2014; Nelson, 2013; Sachs et al., 2009; Smittenberg et al., 2011) to name a few. This presents a challenge when applying paleoclimate data to archaeological situations and trying to interpret evidence of human migration and settlement (e.g. Allen, 2014; Anderson et al., 2006; Goodwin et al., 2014) and fortifications (Field and Lape, 2010) etc. One way to address this challenge is to foster interdisciplinary cooperative efforts between archaeologists and paleoenvironmental specialists (Lape, 2007). To support this effort and discuss key climate factors that influenced tropical Pacific human culture during the mid-late Holocene we propose to host Dr. Melinda N. Allen and Dr. Michael N. Evans.
Dr. Allen is currently an anthropologist at the University of Auckland. She completed her undergraduate work at the University of Arizona and received a Master’s degree from the University of Hawai’i, Manoa. Melinda completed her Ph.D. at the University of Washington in 1992 which examined subsistence and landscape change in the Cook Islands and was a Research Anthropologist at the Bernice Pauahi Bishop Museum in Honolulu (Hawai’i) for five years before joining the University of Auckland’s Department of Anthropology in 1996.
Dr. Evans is currently a paleoclimatologist at the University of Maryland. He was an undergraduate in Environmental Science and Policy at Harvard and completed his Ph.D. in Earth and Environmental Sciences at Columbia University in 1999 followed by Postdoctoral work at LDEO and Harvard. He was a Professor at the Laboratory of Tree-Ring Research at the University of Arizona before moving to the University of Maryland Department of Geology and Earth System Science Interdisciplinary Center in 2008.
Investigating Holocene Ceramics in Peninsular Thailand
We will collect data from archaeological ceramics excavated by a UW archaeology field school from the Khao Toh Chong rockshelter site in Peninsula Thailand to learn about the ‘missing middle’ Holocene period in mainland Southeast Asia. These data will be relevant to understanding the transition from hunting and gathering to a reliance on domesticated resources in Southeast Asia. This is a hotly contested subject, with Higham (2002) claiming a ‘walk in’ scenario of foreign migrants bringing agriculture in from the north, and White (1995) countering that the process of domestication occurred without outside influence.
Termite geoarchaelogy at Madjedbebe, Northern Australia
Madjedbebe (Northern Territory, Australia) is an important location for understanding human evolution. We recently presented new ages of 65 ka for human occupation at Madjedbebe (Clarkson, et al. 2017). These new ages have significance for the arrival humans in Australia, the dispersal of modern humans out of Africa, and the subsequent interactions of modern humans with Neanderthals and Denisovans. However, many factors can influence the relationship between the archaeological material and the dated samples. This project is a geoarchaeological study to improve our understanding of archaeological site formation processes at this important site. We will use three-dimensional shape and size statistics to study the larger size fraction of the sedimentary deposit – cobbles – to test previously posited hypotheses about the role of termites in formation of the deposit at Madjedbebe.
Investigating Vegetation Changes in Northern Australia in the Late Pleistocene – Holocene
Madjebebe in Northern Australia is one of the oldest archaeological sites in Australia, with evidence for human occupation at 50-60 ka (Roberts et. al. 1990a). Because of the age of this site, Madjebebe has the potential to provide insight into the dispersal of modern homo sapiens out of Africa along the southern arc through Southeast Asia.
The samples will be prepared for carbon isotope analysis in the UW Geoarchaeology laboratory as described in Biedenbender et. al. 2004. The organic biomolecule analysis will follow the protocol described in Reber and Evershed (2004) and will be conducted with the assistance of Dr Seungki Kwak, who recently completed his PhD research using the organic geochemistry facilities in the UW School of Oceanography.
Quantifying bed material abrasion to help predict the response of rivers to pulses of sediment supply
Deglaciating alpine catchments represent ideal natural experiments, with large recurring pulses of sediment contributed to the fluvial network from isolated, identifiable source regions. These sediment pulses substantially alter channel morphology on decadal timescales. Taking advantage of this fact, I am working to model the response of basins with varying lithologies to pulses of glaciogenic sediment. I am doing so by combining glaciohydrologic and river channel morphodynamic models, initiated and driven by morphologic data gathered from remote sensing observations, and tested with field measurements of river bed material grain size and lithology.
Key hypothesis: Where glaciers carve especially friable bedrock (such as the headwaters of the Suiattle River), sediment supply perturbations due to deglaciation will transit downstream with the magnitude of morphologic effects decreasing dramatically with distance from the source due to bedload abrasion.
Distal and ultra-distal tephra layers as a dating tool in various fields of the Quaternary studies with special focus on Kamchatka and Kuril Islands
Dated and geochemically fingerprinted tephra layers serve as excellent marker horizons which directly link disparate depositional successions. These layers can be used for dating paleoclimate changes, paleoseismic events and archaeological horizons as well as for compiling a record of hazardous volcanic eruptions. In the frames of this project we are planning to work on two papers. The first one will focus on the Holocene tephrochronological framework for a geodynamically active Kamchatsky Peninsula in Eastern Kamchatka (NW Pacific), where tephra layers permit deciphering of the complicated history of environmental change and natural hazards. The second paper will complement the first one focusing on the Late Glacial-Holocene environmental change in the same area (with Dr. Pendea, Lakehead University, Toronto, Canada). The work will be carried out together with Professor Joanne (Jody) Bourgeois. In addition, I will give a talk on the use of tephrochronology for the Quaternary studies in western Beringia, and hopefully will have a chance to interact with the ESS and QRC students.
River incision driven by changes to woody debris and sediment retention
The proposed project uses field observations, dating, and numerical dating to investigate the short- and long-term effect of sediment retention on river incision and landscape evolution. River incision is thought to be controlled by the balance of sediment supply and transport capacity, with the largest changes in incision rates occurring at glacial-interglacial transitions (e.g., Hancock and Anderson, 2002; Turowski et al., 2007; 2008; Yanites and Tucker, 2010). However, the current framework only considers the transport of sediment and does not take into account any impediments to transport – such as large woody debris (LWD) jams and rockfall – that retain sediment on the riverbed. During enhanced sediment retention, bedrock is protected from erosion by a thick sediment cover (Sklar and Dietrich, 2001); reduced retention will have the opposite impact and promote incision. Such an effect has been noted in streams containing LWD wherein bedrock streams are converted to alluvial by the added retention (Montgomery et al., 1996; Massong and Montgomery, 2000; Faustini and Jones, 2003). Although the conversion of bed-cover has been noted, it is unclear how sediment retention will affect river incision rates. Can a sudden decrease in sediment retention result in significant incision? If so, is the effect of varying retention strong enough to leave a morphologic signature over the Quaternary? We are particularly interested in sediment retention’s impact on strath terrace formation. Strath, or bedrock, terraces are often used to infer Quaternary rates of tectonic deformation (e.g. Personius, 1993; Merritts et al., 1994; Lave and Avouac, 2001); if sediment retention can affect incision rates, then we need to consider changes to sediment retention before making inferences regarding tectonic strain.
An examination of the style and extent of Quaternary deformation in Haida Gwaii driven by subduction initiation
The goal of this project is to determine the effect tectonics has on landscape evolution in the Haida Gwaii archipelago of coastal British Columbia. The 150+ islands of Haida Gwaii are unusual in the context of northwestern America for their proximity to the active transpressive margin between the Pacific and North American plates, elevations in excess of 1 km, as well as their distance from mainland British Columbia. This isolation separated Haida Gwaii from the Cordilleran ice sheet during the last ice age, provided biological refugia (Lacourse et al. 2005) and promoted early human habitation in the Americas (Erlandson et al. 2008). We seek to test the hypothesis that the mountainous topography of Haida Gwaii is geologically young and the product of a nascent subduction zone which initiated 4-6 Mya (Hyndman 2015). We will employ low-temperature thermochronometry as well as examine an extensive lidar dataset for fault scarps to constrain the timing and magnitude of denudation and deformation in Haida Gwaii. Trends in thermochronometry ages will be used to determine the impact subduction initiation has had on the Haida Gwaii landscape. This project will introduce neo-tectonics research to a setting of interest for the QRC, invites an exciting collaboration between the University of Washington, Geologic Survey of Canada, and the Haida Nation, as well as seeds future work on the tectonic and geomorphic evolution of Haida Gwaii.
Bathymetry and hydrography of proglacial Brandywine Lake, British Columbia
Mountains are high-energy environments characterized by instability and variability. Since the end of the Little Ice Age (LIA) about 100 years ago, climate has warmed, causing extensive loss of snow and ice in mountains throughout the world. Downwasting and retreat of glaciers has destabilized alpine geomorphic systems and accelerated some catastrophic natural processes, including outburst floods from moraine- and glacier-dammed lakes.
There has been a recent proliferation of research on ice-ocean interactions especially after the influence of ocean heat and circulation on subaqueous melt of floating ice shelves was recognized. The current research will utilize a new suite of cutting edge instruments including a portable, shallow-water multibeam sonar to collect some of the first high resolution bathymetric measurements in a proglacial lake. These data will contribute to our understanding of how glacial lakes evolve as the glaciers feeding them retreat.
Reconstruction of Holocene temperatures from Greenland lake sediment cores using a novel method: Clumped Isotopes
This project investigates the Northern Hemisphere arctic temperatures during the Holocene. Previous research on lake sediments from Braya Sø and Limnaea Sø found abrupt, large shifts in the carbon isotopes (δ18O and δ13C) over the past ~8,000 years, thought to be driven by changes in evaporation and precipitation [Anderson and Leng, 2004]. Recent research using alkenones from Braya Sø has shown significant (~2-5˚C) temperature variations in West Greenland during similar time periods [D’Andrea et al., 2011]. Both of these paleothermometers depend on changes in the lakes, through changes either in the δ18O composition or in the biological alkenones in response to fluctuating water temperatures. It remains to be determined how much of the reconstructed temperature changes are directly in response to a temperature shift, rather than hydrologic changes. To address this issue, this project uses clumped isotopes to (1) determine if the temperature of lake carbonate formation corresponds to the alkenone data; (2) determine if the purported temperature excursions during the Holocene reflect actual temperature changes; and (3) correct previously published δ18Owater values for temperature dependent fractionation using the actual lake temperatures determined here. The advantage of using clumped isotope measurement is that they give a direct measurement of lake temperature; the amount of clumping during carbonate formation is dependent solely on the temperature.
Constraining material properties and age of Mima Mounds
The Mima Mounds near Olympia, Washington are the archetype for similar appearing mounds around the world. This project seeks to better constraining the time for the formation of the mounding, as well as documenting the nature of the organic matter in the A horizon. An estimate of the time since the mounds have formed will be determined using cosmogenic Be-10. The exposure age of clasts in the center of a mound (shielded by 2+ m of A horizon material) will be compared to the exposure age of clasts from the inter-mound area at depth of a few decimeters. The exposure age will also help determine if the mounds are in a stable positions or if they are dynamically being rebuilt. The dark organic horizons are believed to be from black carbon that formed in the Mima Prairie as it was burned to facilitate the agricultural practices of the Native Americans for growing Camus species, a starch-rich plant that they actively harvested. The black carbon content will be estimated by chemical oxidation followed by Nuclear Magnetic Resonance to measure the aromatic content. To provide additional characterization, the organic matter in particular mounds that are dated by Be-10 and analyzed for black carbon, will be dated by C-14. The data will be interpreted in the context of the prevailing hypothesis of mound formation being formed by gophers. The Mima Mounds will be featured as an excursion for the Geological Society of America conference to be held in Seattle in October 2017, as well as presented in a talk at the memorial session for Steve Porter.
Permafrost distribution in High Mountain Andes
As the Earth experiences climate change, an area that is particularly vulnerable is that underlain by permafrost[2, 3] since thawing affects ecosystems, infrastructure, shoreline stability, and, critically, the water supply for millions of people depending on runoff from the high mountains of Asia and South America. Changes in permafrost are expected to be most extensive in the margins of continuous permafrost and areas of discontinuous permafrost as the mean annual temperature warms above the freezing point of water. Delineating changes in permafrost is challenging and much has been done by land-based observations. These types of observations are labor-intensive and expensive, so it is impractical to monitor changes in permafrost over large regions. The remote-sensed observations are most effective to monitor regional-scale changes in permafrost distribution. This proposal to QRC is to provide proof of concept in mapping and modeling ice-rich permafrost (IRP) in the high mountain area of the Andes. Our proposed work plan includes working with remotely sensed images, using land-based climate data, collecting ground-validation data in the field for the extent of IRP, and determining the active layer depth, and skin temperature by installing logging systems at 4 sites in the Barrancas Blancas regions of Chile.
Workshop: International Phytolith Taxonomy Committee
Plant silica (phytoliths) is an increasingly common tool for answering archaeological, palaeoenvironmental, evolutionary, taxonomic, and climatic questions, often within a multidisciplinary framework. Owing to the diverse fields in which phytolith analysis is applied, the establishment of a universally accepted nomenclature and classification system of phytoliths has lagged behind. This lack of a universal system substantially hinders communication among researchers and inter-study comparisons. An effort to standardize the naming of phytoliths was made by the International Committee for Phytolith Nomenclature (“ICPN 1.0”) in 2005, but suffers from major shortcomings. In addition, a formal way to describe and classify phytolith taxonomic units (‘morphotypes’) is still missing.
In 2015, the ICPT formed, with the purpose of updating and revising the ICPN 1.0, creating a formal procedure/format for phytolith description, and a classification system. The ICPT consists of archaeologists, Quaternary paleoecologists, botanists, and deep-time paleobotanists, representing a cross section of phytolith scientists. After four workshops we have a rough draft of the first publication (‘ICPN 2.0’); however, a fifth workshop is needed to finalize several important aspects and plan out the next steps.
Could the West Antarctic Ice Sheet have Collapsed in the Previous Interglacial Warm Period? A Modeling Assessment based on Stable Isotopes in the Deep Ice from Siple Dome
The Quaternary period is characterized by growth and decay of large ice sheets. Because its bed is far below sea level, the West Antarctic Ice Sheet (WAIS) is vulnerable to the Marine Ice-sheet instability. Octopus populations in the Ross and Weddell seas, but now isolated by WAIS, and marine diatoms recovered from beneath the WAIS indicate that the WAIS was not present at some unknown time in the Quaternary. Stable isotopes of water in the bottom 8 meters of the 1-km-deep Siple Dome ice core imply that the basal ice, which dates from Marine Isotope Stage 5e (130-90 ka) or older, originated at a much higher and colder location than Siple Dome. Prof. Richard Alley at Penn State has suggested that the WAIS collapsed to form a floating ice shelf at some time during Marine Isotope Stage 5e, bringing ice from an unknown high inland location such as the Whitmore Mountains, out into the Ross Embayment, where, as floating a few hundred meters thick, it then grounded on a submarine shoal to form the modern Siple Dome. Subsequent flow in Siple Dome has subsequently reduced its thickness to the current 8 meters.
In this project, ESS undergraduate student, Izzati Ahamad Fouzi, will extend her research on this question by exploring a much wider range of proposed scenarios in order to establish limits on the climate and ice-flow histories that are compatible with the ice-core data. She will also prepare a manuscript for publication on the work. The proposed end result of the project will be a manuscript with Ms Ahamad Fouzi as lead author, to be submitted to a peer-reviewed scientific journal such as Quaternary Research, Journal of Glaciology, or The Cryosphere.