Reinhard Pienitz CEN/Geography Ulaval [email protected] The Pingualuit Crater Lake Project Sonja Hausmann CEN/Geography Ulaval sonja.hausmann@cen. ulaval.ca The Pingualuit Crater is located in the northernmost part of the Ungava Peninsula in northern Quebec.

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Transcript Reinhard Pienitz CEN/Geography Ulaval [email protected] The Pingualuit Crater Lake Project Sonja Hausmann CEN/Geography Ulaval sonja.hausmann@cen. ulaval.ca The Pingualuit Crater is located in the northernmost part of the Ungava Peninsula in northern Quebec.

Reinhard
Pienitz
CEN/Geography Ulaval
[email protected]
The Pingualuit Crater Lake Project
Sonja
Hausmann
CEN/Geography Ulaval
sonja.hausmann@cen.
ulaval.ca
The Pingualuit Crater is located in the
northernmost part of the Ungava
Peninsula in northern Quebec (61o17' N,
73o41' W; Nunavik). The crater is the
result of a meteorite which originated in
the orbits between Jupiter and Mars and
entered Earth’s atmosphere ca. 1.3
million years ago as determined by
Ar/Ar dating of the impactites collected
at the site (Grieve et al. 1989). It is a
nearly perfectly circular depression
about 400 m deep and 3.4 km in
diameter, hosting a lake presently 267
meters deep with no surface connection
to other surrounding water bodies
(Bouchard 1989).
Warwick
Vincent
CEN/Biology Ulaval
[email protected]
Martin
Lavoie
CEN/Geography Ulaval
[email protected]
CORING
May 2007
267 m
The sediment infill promises to yield an
uninterrupted, 1.3 million year arctic
paleoclimate record of several interglacials. Until now, only 15 cm of about
130 m have been recovered with an
Eckman binge by Michel Bouchard.
Due to its unique morphometry (shape,
depth) it is possible that the lake bottom
escaped glacial erosion (Bouchard
1989). Lake Vostok in Antarctica
possibly presents a modern analogue
situation.
Michel Bouchard
Centre des Technologies de
l’Environnement de Tunis
(CITET)
Dept. of Civil Engineering
École Polytechnique
Université de Montréal
[email protected]
Isabelle
Larocque
[email protected]
IRNS/ETE
Pingualuit
• potentially continuous continental
1.3 Ma old climate record
• the basin is fed through direct precipitation only and
therefore is a vast rainwater collector
• without surficial in and outflow
• permafrost down to at least 500 m depth
• the catchment area corresponds to the lake surface
• only the top 15 cm have been investigated they are
rich in pollen, diatoms and chironomids
• ultra-oligotrophic water, 1% light in 87 m
• 275 m deep
Guillaume
St. Onge
GEOTOP/ISMER
[email protected]
Veli-Pekka
Salonen
University of Helsinki
[email protected]
Impact crater
El'gygytgyn
Projected
Treeline
2090
Earth's climate is changing rapidly. These climate changes are being experienced particularly
intensively in the Arctic. Arctic average temperature has risen at almost twice the rate as the
rest of the world in the past few decades (ACIA 2004). These observations have led to public
concern about the potential collapse of infra-structures that depend on permafrost stability,
such as foundations of buildings, roads, pipelines and airport runways.
Present
Treeline
Impact crater
Pingualuit
Richard
Niederreiter
[email protected]
Under the Hadley 3 scenario, the growing season at the Pingualuit Crater lake site will
increase by 30 days between now and 2070-2090 (ACIA 2004). As a consequence, the tree
line is predicted to move 400 km north. In order to test/validate these predictions of future
climate, we need reliable long-term data of past climate change.