To his undergraduate students in chemistry, Assistant Professor Yves Gélinas
is probably just another new young face in the Department of Chemistry
and Biochemistry. What they dont know is that Gélinas is
starting his academic career with a bang: an article in the Oct. 5 issue
of the prestigious journal Science.
Gélinas, whose main interest is in marine organic geochemistry
(MOG), modestly suggested that Science publishes papers about topics
that are newsy, and that his research fits the bill because
it is related to a current hot topic, the global carbon cycle. Nevertheless,
he added, it settles a 20-year-old debate among petroleum scientists.
Transformation of organic
Gélinas, who just arrived at Concordia, wrote this article as a
postdoctoral fellow at the University of Washington in Seattle. There,
his advisor was John I. Hedges, a man Gélinas considers a genius.
In his research, Hedges uses various techniques to study marine organic
Collaborating also with Jeffrey A. Baldock, a Canadian scientist living
in Adelaide, Australia, Gélinas looked at factors affecting the
transformation of organic matter to petroleum in ocean sediments.
He explained that some of the organic matter produced at the ocean surface
eventually settles on the bottom. Most of it decomposes, giving off carbon
dioxide in the process, but a small amount is preserved in sediments.
Over thousands of years, as more and more sediment builds up, the organic
matter reaches a depth where high temperature and pressure transform it
into petroleum. Gélinas was interested in the decomposition of
freshly deposited organic matter, and in the effect oxygen has on this
process. Some organic matter is only degraded when oxygen is present,
and it is this type of organic matter that is the precursor of petroleum.
In 1980, a model was introduced that tried to explain the conditions
that were necessary for petroleum to form in sediments at the bottom of
the ocean, he explained. That model stated that you had to
have conditions with no oxygen for the formation of petroleum.
Someone else challenged that model in the mid-80s with a different
idea. Since then, people have assumed that the first model was right,
but there was no demonstration to prove it, Gélinas said.
We think we have a good answer confirming the first hypothesis that
will settle this debate once and for all.
The study looked at core samples of sediments Hedges had collected from
oceans around the world. Gélinas also spent a month off the coast
of Mexico, collecting additional samples. During my years in Seattle,
I developed a method to remove the minerals from these sediments so you
can concentrate the organic matter. We then tested these samples with
NMR spectroscopy, a tool used to probe their molecular structure.
What is most important to him about this line of research is the wealth
of information contained in marine sediments.
When you take a core sample of sediment from the bottom of the ocean,
you have an exquisitely detailed record of the history of life on Earth.
A Quebecer, Gélinas did his undergraduate and graduate work at
UQAM, followed by a year at University of Massachusetts in Amherst, and
three and a half years in Seattle.
Now he is happy to be back in Montreal, and excited about the prospect
of continuing his research interests in marine organic geochemistry with
colleagues at Concordia, McGill and UQAM. In a few years, he will also
teach a graduate-level course in aquatic chemistry at Concordia.