Determining bioturbation rates and ocean productivity through geochemical paleo-proxies
Presentation Type
Abstract
Faculty Advisor
Sandra Passchier
Access Type
Event
Start Date
25-4-2025 12:00 PM
End Date
25-4-2025 1:00 PM
Description
The Greenland Ice Sheet (GrIS) has demonstrated sensitivity to climate warming and a poorly constrained response to major climate shifts. The International Ocean Discovery Program (IODP) pilots drilling expeditions to help understand past climates and paleoenvironments by extracting long cores from sedimentary layers overlying the crust that represent different intervals in geologic time. IODP Expedition 400 addresses the GrIS retreat by drilling more than 90 cores in a transect across Greenland’s Northwestern coast along Baffin Bay, spanning the last 30-50 million years. We can understand how these cores correlate to the paleoenvironment of GrIS fluctuations using different forcing mechanisms. This study focuses on reconstructing paleo-productivity in Baffin Bay using geochemical paleo-proxies. The cores from Site 1608A, specifically during the Pliocene period (5.3 million years ago) exhibit trace fossils of small worm burrows throughout the core sample, a phenomenon known as bioturbation. This could be due to a myriad of paleoenvironmental factors. Excess elemental concentrations could reflect phytoplankton productivity in the water column, potentially indicating increased nutrient availability during warm intervals within the cooling Pliocene. The Arctic water column remains understudied, and understanding these variations is crucial for future oceanic warming responses. Fluctuating trace element concentrations, specifically barium, are used to detect changes in surface productivity during periods of enhanced bioturbation. This study will contribute to the scientific understanding of ocean-atmosphere interaction in support of mitigation efforts in future warming scenarios.
Determining bioturbation rates and ocean productivity through geochemical paleo-proxies
The Greenland Ice Sheet (GrIS) has demonstrated sensitivity to climate warming and a poorly constrained response to major climate shifts. The International Ocean Discovery Program (IODP) pilots drilling expeditions to help understand past climates and paleoenvironments by extracting long cores from sedimentary layers overlying the crust that represent different intervals in geologic time. IODP Expedition 400 addresses the GrIS retreat by drilling more than 90 cores in a transect across Greenland’s Northwestern coast along Baffin Bay, spanning the last 30-50 million years. We can understand how these cores correlate to the paleoenvironment of GrIS fluctuations using different forcing mechanisms. This study focuses on reconstructing paleo-productivity in Baffin Bay using geochemical paleo-proxies. The cores from Site 1608A, specifically during the Pliocene period (5.3 million years ago) exhibit trace fossils of small worm burrows throughout the core sample, a phenomenon known as bioturbation. This could be due to a myriad of paleoenvironmental factors. Excess elemental concentrations could reflect phytoplankton productivity in the water column, potentially indicating increased nutrient availability during warm intervals within the cooling Pliocene. The Arctic water column remains understudied, and understanding these variations is crucial for future oceanic warming responses. Fluctuating trace element concentrations, specifically barium, are used to detect changes in surface productivity during periods of enhanced bioturbation. This study will contribute to the scientific understanding of ocean-atmosphere interaction in support of mitigation efforts in future warming scenarios.
Comments
Poster presentation at the 2025 Student Research Symposium.