Sunday, February 26, 2017

Join us for dinner, socializing and a thought-provoking presentation at the Current River Community Centre.

The TBFN Annual Dinner Meeting will be held at the Current Recreation Community Centre on Sunday, February 26, 2017. Symposium 4:30 pm,  Supper 5:45pm. There will be a cash bar. Tickets will be $30.00 each and available at the November and January general meetings and on the TBFN website (online membership form) through PayPal.

Note - Tickets will not be available at the door. They must be purchased in advance.

The last day for purchasing tickets is Sunday, 19 February

Contact information for the dinner is Susan Robinson, email hitchcroft(at)shaw(dot)ca or phone 344-1739.

This year's guest speaker is Dr. Phil Fralick, Lakehead University, Department of Geology.

His topic is: 

Evolution of Earth’s Atmosphere from 1,500 to 3,000 Million Years Ago:  Evidence from Rocks in Northwestern Ontario

In the past people mostly took the Earth’s atmosphere for granted, that is until about forty years ago when papers speculating about the possibility of man-made global warming began to appear. Over the ensuing decades the fragility of our atmosphere has become apparent. In this talk we’ll go back in time to the early Earth and explore how the atmosphere we have today developed. In particular, the evolution of photosynthesis caused a cascade of changes to the atmosphere and ocean that stabilized Earth’s climate, after first causing the Planet to freeze for a few million years, and allowed multicellular life to evolve. Much of the research into these changes has been conducted in northwestern Ontario and this talk will discuss how the Precambrian rocks of the area have added significantly to the story of how the early atmosphere-ocean-biosphere system evolved.

We’ll examine evidence for the first traces of photosynthesis in shallow water limestones from the Red Lake and Atikokan areas, investigate rocks from north of Lake Huron that show how a major increase in oxygen to about one percent of the atmosphere at 2,400 million years ago eradicated atmospheric methane and caused Earth’s temperature to crash, evaluate evidence in the Gunflint Formation underlying Thunder Bay that major submarine volcanism at 1,900 million years ago caused the ocean to become anoxic, and look at evidence from the red rocks in the Nipigon area that indicate the atmospheric oxygen level had risen to 4 percent by 1,500 million years ago.