Quaternary history, palaeo-geography and sedimentology of the Humber River Basin and adjacent areas

• Main Author: Batterson, Martin J. (Martin Jonathan)
• Format: Thesis
• Language: English
• Published: Memorial University of Newfoundland 1998
• Subjects: Deer Lake; Glacial Lake; South Brook; Newfoundland
• Online Access: https://research.library.mun.ca/6646/; https://research.library.mun.ca/6646/1/MartinJonathanBatterson2.pdf; https://research.library.mun.ca/6646/3/MartinJonathanBatterson2.pdf

The Humber River basin in western Newfoundland was completely glaciated during the Quaternary. Glacial erosional features show an early southward ice flow from a source north of the basin that covered the coastal margins in the western part of the basin, including the Harrys River valley. Subsequent regional ice flow was southwestward to northwestward from a dispersal centre on The Topsails. South to southwestward flowing ice from the Long Range Mountains occupied the upper Humber River valley. This flow was confluent with ice from The Topsails flowing northwestward towards Bonne Bay. -- Ice retreated from the inner coast about 13 ka. During retreat, ice occupying the Deer Lake Valley dammed a proglacial lake in the adjacent Grand Lake basin to an elevation up to 85 m above present lake levels, as interpreted from strandlines on the west side and deltas on the east. This lake, named glacial Lake Howley, drained through its western end into the Harrys River valley via a well-defined channel. Drainage followed the modem Harrys River valley, reaching the sea in northern St. George's Bay. The lake was lowered by exposure of the South Brook valley outlet, and finally drained catastrophically through a spillway at Junction Brook. -- Marine incursion accompanied glacial retreat in the Deer Lake valley. Marine limit at the coast was 60 m asl, based on the elevation of a delta in the Hughes Brook valley. Inland deltas found at the head of Deer Lake and fine-grained sediment exposed within the Deer Lake valley show inundation below 45 m modem elevation. Dated marine macro-fossils in the Humber Arm and lower Humber River valley, indicate the deltas at the head of Deer Lake formed about 12.5 ka.