Nunavut's Mysterious Ancient Life Could Return by 2100 as Arctic Warms

[xchrom]

http://www.sciencedaily.com/releases/2012/09/120921082807.htm

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View from the study site at the beginning of the fieldwork in the end of June 2010. (Credit: Alexandre Guertin-Pasquier)

ScienceDaily (Sep. 21, 2012) — Global climate change means that recently discovered ancient forests in Canada's extreme north could one day return, according to Alexandre Guertin-Pasquier of the University of Montreal's Department of Geography, who is presenting his findings at the Canadian Paleontology Conference in Toronto today.

According to the data model, climate conditions on Bylot Island will be able to support the kinds of trees we find in the fossilized forest that currently exist there, such as willow, pine and spruce. I've also found evidence of a possible growth of oak and hickory near the study site during this period," Guertin-Pasquier said. "Although it would of course take time for a whole forest to regrow, the findings show that our grandchildren should be able to plant a tree and watch it grow."

The fossilized forest found on Bylot Island in Nunavut is between 2.6 and 3 million years old according to estimations based on the presence of extinct species and on paleomagnetic analyses. Paleomagentic analysis involves looking at how Earth's magnetic field has affected the magnetic sediment in rocks -- like a compass, they turn to follow the magnetic poles. Scientists can use this information to date rocks as the history of the movement of the magnetic poles is relatively well known.

[Nihil]

1. Umm ... really?

> Paleomagentic analysis involves looking at how Earth's magnetic field has affected
> the magnetic sediment in rocks -- like a compass, they turn to follow the magnetic poles.

Not when I was being taught it: it involves igneous (primarily volcanic) rock and there
is no "sediment" involved. When the rock solidifies, it provides an indication of the
predominant magnetic field at that time & place (and hence can be used to provide a
measure of locational & temporal information) but once erosion strikes the igneous
rock, that location information is rendered useless (because the particles have been
moved from their original orientation) and so cannot be used to derive any date
information from a paleomagnetic basis.

Let's hope that the rest of the article is more accurate ...

[Canuckistanian]

3. Detrital remanent magnetization (DRM)

Detrital remanent magnetization

In a completely different process, magnetic grains in sediments may align with the magnetic field during or soon after deposition; this is known as detrital remanent magnetization (DRM). If the magnetization is acquired as the grains are deposited, the result is a depositional detrital remanent magnetization (dDRM); if it is acquired soon after deposition, it is a post-depositional detrital remanent magnetization (pDRM).[6]

http://en.wikipedia.org/wiki/Paleomagnetism

[Nihil]

4. Interesting ...

I checked back and dDRM *was* mentioned back then - only in passing - as an effect that was
noted but "not significantly useful for paleomagnetic purposes". Technology (and the science
in general) has undoubtably advanced since then.

Thanks for the update!

[friendly_iconoclast]

2. I've heard about the ancient forest before. Here's a pic:

[NickB79]

5. Oaks and hickory in the Arctic Circle. Amazing

I guess by then my grandchildren will be planting palm trees here in Minnesota.