Hannah Chorley

Hannah Chorley

Contact

Phone: 04 463 5233 x 8619
Email: Hannah.Chorley@vuw.ac.nz
Office: CO523

Qualifications

BSc Coventry University (2015); MSc University of Bristol (2016)
PhD Candidate in Paleoclimatology

PhD thesis

Title

Environmental and Climatic Reconstruction of the Friis Hills, Transantarctic Mountains during the Early to mid-Miocene.

Supervisor

Project objectives and description

This project aims to contribute to developing an understanding of Early to Mid-Miocene East Antarctic Ice Sheet variability. This will be achieved through the sequence stratigraphy and facies analysis of the Friis Hills Drilling Project (FHDP) drill cores and subsequent localised and continental scale ice sheet modelling to reconstruct these conditions and better understand the dynamic nature of the East Antarctic Ice Sheet (EAIS) during the Miocene.

The Friis Hills Drilling Project drill cores, collected during the austral summer season of 2016/17, offer direct evidence of EAIS variability in the TAM during the warmer-than present Miocene. Detailed sequence stratigraphy and facies analysis will be supported by physical property, XRF data, CT scans, and grain size analysis. So far, ten sedimentary facies have been identified, representing regular oscillations in a depositional setting along a continuum from subglacial to ice distal lacustrine environments. These terrestrial constraints will also provide comparison to other records of similar age such as those from ANDRILL-2A and newly recovered records from IODP Expedition 374. Uncertainty in uplift rates in the TAM since the Miocene complicates paleoclimatic interpretation, with inferred uplift rates of up to 100 m my-1 (Fitzgerald 1992) placing the Friis Hills, with an average modern-day elevation of 1325m, considerably closer to sea level. Furthermore, previous work by Lewis and Ashworth (2016) indicates a shift in the direction of flow of the EAIS over time, with FHDP deposits predating the downcutting of the Pearse and Taylor Valleys. A variety of ice sheet model experiments will be designed to investigate the influence of a range of different topographies on the development of ice over the Friis Hills, using data from the Friis Hills and other records as constraints on glacial and climate conditions