Alluvial, eolian and lacustrine sedimentology of a Paleoproterozoic half-graben, Baker Lake Basin, Nunavut, Canada |
| |
Authors: | Thomas Hadlari Robert H Rainbird J Allan Donaldson |
| |
Institution: | aDepartment of Earth Sciences, Carleton University, Ottawa, Ontario, Canada K1S 5B6 bGeological Survey of Canada, 601 Booth St., Ottawa, Ont., Canada K1A 0E8 |
| |
Abstract: | The northeast-trending Baker Lake sub-basin was a volcanically active, half-graben during deposition of ca. 1.85–1.76 Ga Baker Lake Group. Drainage was oriented along transverse and axial directions with flow to playa lake and deeper perennial lacustrine depocentres. Basin marginal, streamflow-dominated alluvial fans were concentrated along the southern margin, and provided sediment from Archean crystalline basement rocks. These fed transverse gravel- and sand-bed braided streams. Alluvial dynamics were characterized by channel aggradation and abandonment. Abandoned channel belts were sites of floodplain and eolian deposition. Basin axial braided streams fed northeast and southwest to a depocentre near Christopher Island, where eolian, playa and lacustrine environments were intimately linked. Felsic minette flows were initially erupted from localized centres; contemporaneous sedimentary deposits typically contain minor volcaniclastic components that increase in abundance basinward. Voluminous and widespread younger minette flows prograded outward from volcanic centres contributing significant additional basin-infill. |
| |
Keywords: | Alluvial fan Braided stream Floodplain Eolian Lacustrine Half-graben |
本文献已被 ScienceDirect 等数据库收录! |
|