4 ms·
The formation of the great lakes was an eye-blink ago on the scale of this map. They are only about four times as old as the great pyramid (woah)
by jbattle 7y ago
The formation of the great lakes was an eye-blink ago on the scale of this map. They are only about four times as old as the great pyramid (woah)
- mncharity 7y agoThe maps are hand-painted representations of the various ages. On the earlier maps, there was a lot of care, but also unavoidably a lot of handwaving. For the 0 Ma map, I don't know if Scotese had a particular time in mind? It looks like modern coastlines, which means an interglacial period. A 100 ky average would be more glacial - the Boston coast would stick out more. I suspect he simply used the current coast. The absence of the Great Lakes, suggests it's not the current interglacial. A duration-weighted average of say the last 1 My of 10-ish interglacials might fade the Lakes to invisibility. So perhaps it's an eye blink of averaged interglacials, or a recent but previous interglacial, or a map rule like "don't include transient features", or a consistency of approach (eg, disregarding flavors of data unavailable for earlier maps, except for the coastline), or ... ?