Comments on "Assessing the ages of the Moorhead and Emerson phases of glacial Lake Agassiz and their temporal connection to the Younger Dryas cold reversal" by Joseph M. Young, Alberto V. Reyes, and Duane G. Froese. (15th March 2021)

• Record Type: Journal Article
• Authors: Teller, James T.
• Is Part Of: Quaternary science reviews. Volume 256(2021)
• Publication Date: 2021-03-15
• Subjects: Geology, Stratigraphic -- Quaternary -- Periodicals; Stratigraphie -- Quaternaire -- Périodiques; 551.79
• DOI: 10.1016/j.quascirev.2021.106836
• Languages: English
• ISSNs: 0277-3791

Abstract

Abstract: The paucity of radiocarbon ages in Lake Agassiz sediments between 12.9 and 12.4 ka probably reflects conditions in the lake that were unsuitable for the growth and accumulation of datable vegetation, not a delay in the time when the level of the lake declined. Thus, it does not seem appropriate to reject an apparent coincidence of the time of a major drop of the lake to the Moorhead low-water phase with the start of the Younger Dryas at 12.9 ka. Furthermore, the so-called Emerson phase of Lake Agassiz that followed the Moorhead phase was not a prolonged period of lake stability, only a brief time when the lake reached its maximum transgressive limit, stranding the Campbell beach before receding; dates older than ∼10.6 ka reflect sediments deposited during, or reworked from, the Moorhead low-water phase.