Friis Hills Drilling Project: An International Collaboration to Examine the Miocene Transition in Antarctica

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Scientific drilling in Antarctica allows scientists to gather detailed information about past periods of global climate variability. Previous drilling projects that targeted marine sediments have shown that Antarctica experienced a major cooling event about 15 million years ago. Previous studies of surface sediments in the Friis Hills, located in the Dry Valleys of Antarctica, suggested that this transition at 15 million years ago shifted Antarctica from a vegetated to a glaciated environment. This project is targeting terrestrial drilling sites in the Friis Hills to collect cores of ancient and well-preserved lake sediment that can be compared to the marine sediment cores and surface deposits. Volcanic ash layers from the core and surface deposits can be dated and correlated to constrain the timing of climate transition in Antarctica. The combined data set of the marine and lake sediment cores will give scientists a more complete picture of past climate events as they compare environmental data across a broad onshore-offshore transect for the Antarctic continent. The US investigators supported by this RAPID (Rapid Response Research) project will join a research team from New Zealand and Italy to conduct the drilling and collect multiple lake sediment cores. This novel dataset will provide the oldest continuous sedimentary record in the terrestrial Antarctic and thus help to answer long-standing questions of biogeography including: (1) When did the Neogene tundra biota become extinct? (2) Was the climate change that caused the biotic turnover unidirectional and permanent; or, did short-lived, warmer-climatic conditions that supported tundra, return to the Dry Valleys after the mid-Miocene? (3) Were any possible warmer conditions regional or continental in their extent? (4) How closely linked are the records for Neogene climate evolution and Neogene landscape evolution in the western Dry Valleys region? The U.S. participants in this project are responsible for the following objectives: (1) establish chronology of the Friis Hills core by 40Ar/39Ar dating of crystals from ash layers found in the core, (2) correlate the published outcrop record from surface sediments to the forthcoming Friis Hills core stratigraphy, and (3) characterize the microclimate of Friis Hills for future ice sheet and climate modeling initiatives. The project benefits an early career researcher and provides training for a graduate student. Dissemination of results and products will be via peer-reviewed publications and conference abstracts and will be highlighted in the novel AntarcticKids program at Worcester State University, MA, aimed at attracting K-8 school students to science.