A5029853741- Geology and Paleoclimatology Research
- Cryospheric studies and observations
- Paleontology and Stratigraphy of Fossils
- Polar Research and Ecology
- Geochemistry and Elemental Analysis
- Geological and Geochemical Analysis
- Pleistocene-Era Hominins and Archaeology
- Methane Hydrates and Related Phenomena
- Winter Sports Injuries and Performance
- Isotope Analysis in Ecology
- Landslides and related hazards
- Climate change and permafrost
- Geochemistry and Geologic Mapping
- Forensic and Genetic Research
- Forensic Anthropology and Bioarchaeology Studies
- Marine Biology and Ecology Research
- Evolution and Paleontology Studies
- Marine and coastal plant biology
- Geological formations and processes
- Marine and environmental studies
- Arctic and Antarctic ice dynamics
Imperial College London
2021-2025
Durham University
2017
Abstract Oscillations in ice sheet extent during early and middle Miocene are intermittently preserved the sedimentary record from Antarctic continental shelf, with widespread erosion occurring major advances, open marine deposition times of retreat. Data seismic reflection surveys drill sites Deep Sea Drilling Project Leg 28 International Ocean Discovery Program Expedition 374, located across present-day shelf central Ross (Antarctica), indicate presence expanded to sections. These include...
Abstract. Ice sheet models should be able to accurately simulate palaeo ice sheets have confidence in their projections of future polar mass loss and resulting global sea level rise. This requires accurate reconstructions the extent flow patterns using real-world data. Such can achieved by tracing detrital components offshore sedimentary records back source areas on land. For Antarctica, however, sediment provenance data model results not been directly linked, despite complementary...
Recent work demonstrates that the Skytrain ice core, retrieved from Weddell Sea Embayment in West Antarctica, can inform us about (in-)stability of Ronne-Filcher Ice Shelf and Antarctic Sheet past warm periods. Here we switch our focus to Last Glacial period at describe “Calcium Conundrum”, which may be linked sheet dynamics. The calcium record diverges those other cores across several distinct time intervals. The increased Ca is not accompanied by a...
Abstract Beneath Antarctica’s ice sheets, a little-observed network of liquid water connects vast landscapes and contributes to the motion overriding ice. When this subglacial reaches ocean cavity beneath shelves, it mixes with seawater, amplifying melt in places forming deep channels base Here we present observations from hot-water-drilled borehole documenting entering at grounding zone Kamb Ice Stream Ross Shelf. Our show that has removed approximately third thickness, yet measurements...
Abstract Provenance records from sediments deposited offshore of the West Antarctic Ice Sheet (WAIS) can help identify past major ice retreat, thus constraining ice‐sheet models projecting future sea‐level rise. Interpretations such are, however, hampered by obscuring Antarctica's geology. Here, we explore central subglacial geology using basal debris within Byrd core, drilled to bed in 1968. Sand grain microtextures and a high kaolinite content (∼38–42%) reveal consists predominantly eroded...
The warmer-than-present interglacial periods of the late Pleistocene provide closest palaeo analogues to inform predictions Antarctic ice sheet mass loss over coming decades and centuries. However, response Antarctica’s sheets environmental conditions during these remains poorly constrained, resulting in significant uncertainties model future sea-level rise. Here, sediment provenance analyses (Nd Sr isotope compositions, detrital zircon U-Pb dates heavy mineral counts) reveal...
Marine δ 18 O data reveal astronomical forcing of the climate and cryosphere during Miocene, when atmospheric P co 2 was on par with emissions scenarios over next century. This inspired hypotheses for how Milankovitch cycles, ice-ocean interactions, greenhouse gases influence ice volume. Mass balance controls marine terrestrial sheets differ, proxy collected far from Antarctica provide valuable but limited insight into regional processes. We evaluate clast abundance Antarctic sedimentary...
Abstract Large-scale geological structures have controlled the long-term development of bed and thus flow West Antarctic Ice Sheet (WAIS). However, complete ice cover has obscured age exact positions faults boundaries beneath Thwaites Glacier Pine Island Glacier, two major WAIS outlets in Amundsen Sea sector. Here, we characterize only rock outcrop between these glaciers, which was exposed by retreat slow-flowing coastal early 2010s to form new Sif Island. The island comprises granite,...
Abstract Pliocene global temperatures periodically exceeded modern levels, offering insights into ice sheet sensitivity to warm climates. Ice-proximal geologic records from this period provide crucial but limited glimpses of Antarctic Ice Sheet behavior. We use an model driven by climate snapshots simulate transient glacial cyclicity 4.5 2.6 Ma, providing spatial and temporal context for records. By evaluating simulations against a comprehensive synthesis data, we translate the intermittent...
Abstract. Ice sheet models must be able to accurately simulate palaeo ice sheets have confidence in their projections of future polar mass loss and resulting global sea-level rise, particularly over longer timescales. This requires accurate reconstructions the extent flow patterns using real-world data. Such can achieved by tracing detrital components offshore sedimentary records back source areas on land. For Antarctica, however, sediment provenance data model results not been directly...
Despite a major effort to constrain peak sea level during the mid-Pliocene warm period, uncertainties remain large. This interval is of interest because analogous CO2 concentration present day and potential retreat large portion Antarctic Ice Sheet. The usefulness this period ice sheet model physics limited by these on level. Here we discuss efforts produce new record amplitude change from interglacial glacial periods early mid-Pliocene, which have lower than We combine with climate...
A number of studies have defined a boundary in the Amundsen Sea embayment between an inner continental shelf, which contains areas where crystalline bedrock is at or near seabed, and shelf further offshore, underlain by sedimentary strata that increase overall thickness oceanward. Other shown much Pine Island Bay covered drape sandy mud averaging about 1 m thickness, interpreted as having been deposited from meltwater plumes during mid-late Holocene. Much thicker sediments to be present...
Drill cores from the Antarctic continental shelf are essential for directly constraining changes in past Ice Sheet extent. Here, we provide a sedimentary facies analysis of drill International Ocean Discovery Program (IODP) Site U1521 Ross Sea, which reveals unique, detailed snapshot evolution between ca. 18 Ma and 13 Ma. We identify distinct depositional packages, each contains successions that reflective baseline shifts presence or absence marine-terminating ice sheets on outermost Sea...
<p>Tracing the provenance of Antarctic sediments yields unique insights into form and flow past ice sheets. However, sediment studies are typically limited to qualitative interpretations by uncertainties regarding subglacial geology, glacial erosion, transport both subglacially beyond sheet margin. Here, we forward model marine geochemical data, in particular neodymium isotope ratios. Numerical ice-sheet modelling predicts spatial pattern erosion rates for a given...
Abstract. Ice sheet models must be able to accurately simulate palaeo ice sheets have confidence in their predictions of future Antarctic mass loss and resulting global sea-level rise, particularly over longer timescales. This requires accurate reconstructions the extent flow patterns using real-world data. Such can achieved by tracing detrital components offshore sedimentary records back source areas on land. However, sediment provenance data model results not been directly linked, despite...