Submission + - Study finds evidence for ancient icebergs off Miami (sciencemag.org)
sciencehabit writes: As the last ice age waned and climate warmed, immense lakes of glacial meltwater that accumulated behind natural ice dams occasionally burst forth from the mouth of Canada’s Hudson Bay and the Gulf of St. Lawrence. When those iceberg-laden outburst floods—some of them carrying more than 1 million cubic meters of water per second and lasting several months—reached the open sea, they took a right turn and flowed south along the coast as far as the Florida Keys, a new study suggests. The torrent-driven icebergs, some of them hundreds of meters thick, plowed troughs in the sea floor all along the continental shelf . Sea levels have risen more than 100 meters since most of these troughs were formed, which has helped preserve them from surface waves that could roil and smooth seafloor sediments. Some of the iceberg scours off Miami Beach, probably created by icebergs the size of those setting sail from Greenland today, lie less than 12 kilometers offshore.
