Lateral Variations in Sediment Provenance and Grain Size along the Baffin Island Slope
Baffin Bay is a 689,000 km2 basin linking the Arctic and the North Atlantic oceans. Nearby ice sheets and their ice streams are responsible for eroding, transporting, and depositing sediment of various size fractions on the sea floor. For over thirty years, geologists have known of the presence of...
Main Author: | |
---|---|
Format: | Text |
Language: | unknown |
Published: |
CU Scholar
2016
|
Subjects: | |
Online Access: | https://scholar.colorado.edu/honr_theses/1107 https://scholar.colorado.edu/cgi/viewcontent.cgi?article=2346&context=honr_theses |
Summary: | Baffin Bay is a 689,000 km2 basin linking the Arctic and the North Atlantic oceans. Nearby ice sheets and their ice streams are responsible for eroding, transporting, and depositing sediment of various size fractions on the sea floor. For over thirty years, geologists have known of the presence of detrital carbonate-rich (DC-) facies in the Baffin Bay Quaternary sediment sequence. It has been demonstrated that the distribution of marine carbonate facies, carbonate sources on land, and carbonate on the floors of the large Canadian Arctic Channels can reveal a relationship between land and sea records. This thesis aims to examine whether there are relationships between grain size and mineralogy in, as well as the sediment provenance of, two cores collected from Baffin Bay (HU2013029-067PC and HU2013029-077PC and TWC) based on the measurement of a number of sediment proxies used to evaluate erosion, transport and deposition. Namely, quantitative x-ray diffraction, particle size analysis, mass magnetic susceptibility, and ice-rafted debris counts are used. Surprisingly, radiocarbon dates from 067 indicate a high rate of sediment accumulation (~1.5 m/ky) during the Holocene, whereas dates on 077 indicate much slower rates of accumulation and extend back >14.35 cal ka BP. Initial results indicate that the two cores have differing provenances: sediment in core 067 is influence by meltwater from Pond Inlet, and core 077 may be influenced by the carbonate-rich material in Foxe Basin. Core 077 may also show evidence of DC-events which correlate to the master chronology of DC events in Baffin Bay. |
---|