Researchers ID unique geological 'sombrero' uplift in South America (Ruh-Roh!)

http://phys.org ^ | 10-11-12 | Provided by University of California - San Diego

[BenLurkin]

Nuts...and I was thinking of moving to Chili....

[gleeaikin]

There was one anomaly in the article. The writer says nothing of this magnitude has occurred in human history. Actually, he should have said historical times, because the great Toba Megavolcano, which left a caldera 18 by 65 miles was about 73,000 years ago, definitely after homo sapiens had developed, causing a sharp reduction in available genetic material. Some scientists suggest that humans were reduced to no more than 5 or 10 thousand individuals by multiple years of “nuclear winter”.

[SunkenCiv]

There’s no way to know about any reduction or ‘bottleneck’, that’s merest speculation. A volcano is a pimple on the planet’s derriere’ compared with a bolide. (nyah nyah) ;’)

[SunkenCiv]

I could live on their baby back ribs.

[fso301]

You’re thinking of the Muslim Triangle where Argentina, Brazil and Paraguay join. It’s 2/3 of the way across the continent to the east of this giant diaper.

Thanks.

[gleeaikin]

A boloid can do much more harm if big enough. The Chesapeake meteor of 34 million years ago left a crater about 60 miles in diameter and resulted in a number of extinctions. However, Toba left a crater 18 miles by 65 miles, and that is a rather large carbuncle not just a pimple. The “speculation” is based on some detailed DNA analysis not just speculation, although I have also heard that it may have been something at least 125,000 years ago that caused the “bottleneck”.

[SunkenCiv]

It’s speculation because there’s no actual data, just estimates as to the rate of change from a hypothetical beginning point — so there is no real data of any bottleneck, either 70K or 125K years ago.