Stable isotope exchange studies and their application to geological problems

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1) The use of stable isotopes to solve geological and environmental problems is now routine world wide, particularly at Canadian universities. The proportion of isotopes vary in the common elements that make up minerals, waters, gases and living matter. Geological and biological processes imprint particular isotope ratios. Practical applications follow for isotopic compositions are often effective tags. I have shown that even though natural gases in oil fields of W. Canada are similar in chemical make up, the gases have characteristic carbon isotope signatures that effectively identifies their source. The isotopic fingerprint of leaking gases is now used as a powerful tool to find the specific source-depth of gas leaking from oil and gas wells. Past success has been on conventional oil and gas wells of W. Canada but the advent of the shale gas boom has brought drilling to New Brunswick, Quebec and Ontario. We suggested that prolific commercial shale gases have a unique isotope fingerprint as a result of being generated in a closed system. We will test that suggestion on shale gases from all parts of N. America. This will not only be important for exploration and development of shale gas but also will serve as a template to identify the source of gases in groundwater. The public's fear of groundwater contamination by resource wells is well documented in the daily news. Deep shale gases may enter shallow groundwater not only from drilling and fracking but also along natural faults. I will initiate a search for natural gas seeps in regions targeted for shale gas development to test if groundwater is already impacted by natural shale gas leakage prior to any drilling. 2) I have combined organic isotope geochemistry, paleoclimatology and palaeoentomology to study amber and tree resins. We have already shown that Baltic amber does not come from pine nor Araucaria trees but rather from extinct relatives of the Japanese umbrella tree. We have also seen a profound isotope shift in resins from trees infected with Mt. pine beetles. Now I will analyze ambers that entomb insects to unravel the ecology of the amber forests. Ambers and resins can be found over a long geological record and we are analyzing them as proxies for climate change.