Geoarchaeological characterisation of a Younger Dryas site in the Alpine uplands: Cornafessa rock shelter (Italy)

Meltwater routing and the Younger Dryas.

The Younger Dryas--the last major cold episode on Earth--is generally considered to have been triggered by a meltwater flood into the North Atlantic. The prevailing hypothesis, proposed by Broecker et al. [1989 Nature 341:318-321] more than two decades ago, suggests that an abrupt rerouting of Lake Agassiz overflow through the Great Lakes and St. Lawrence Valley inhibited deep water formation i...

Inconsistent impact hypotheses for the Younger Dryas.

Israde-Alcántara et al. (1) presented evidence from Lake Cuitzeo sediments and argued that it supports the Younger Dryas (YD) impact hypothesis of Firestone et al. (2) for a major extraterrestrial impact event “involving multiple airburst(s) and/or ground impact(s) at 12.9 ka.” Firestone et al. (2) did not specify the details of the impact but proposed that it had “continentwide effects” and wa...

A Blind Test of the Younger Dryas Impact Hypothesis

The Younger Dryas Impact Hypothesis (YDIH) states that North America was devastated by some sort of extraterrestrial event ~12,800 calendar years before present. Two fundamental questions persist in the debate over the YDIH: Can the results of analyses for purported impact indicators be reproduced? And are the indicators unique to the lower YD boundary (YDB), i.e., ~12.8k cal yrs BP? A test rep...

Speculations on a schematic theory of the Younger Dryas

The possible implications of a change in deep ocean mixing generated by the abrupt coverage of continental shelves during deglaciation is explored schematically. A simple Cartesian continental shelf/deep ocean tidal model is used to mimic the behavior of tidal dissipation at a variety of frequencies relative to a basin-near-resonance. The actual estimated sea level curve is then used to calcula...

Geology. Was the Younger Dryas triggered by a flood?