Bill Addison and Greg Brumpton are the first joint recipients of the Goldich Medal of the Institute on Lake Superior Geology. It is my privilege and pleasure to make this presentation in recognition of their remarkable contributions to the geology of the Lake Superior region. Bill and Greg worked as an inseparable team for more than a decade in the search for, and eventual discovery of the Sudbury impact layer, a bed containing material ejected from the crater near Sudbury, Ontario by the giant impact event at 1850 Ma. Their discovery and resulting publications constitute a fundamental contribution to the geology of the region and have ignited a renewed interest by many colleagues in studies of the classic geology of the iron ranges of the region where extensions of their original discoveries have since been documented.
Before further discussing their scientific contributions I would like to present some biographical information on each of our medalists. Unlike so many of our career-long members, Bill and Greg appeared on our scene with a bang within the past decade, as mature, fully-formed researchers with something truly important to tell us. In assembling this biographical sketch it became apparent that virtually no one in the geologic community knew much of their pre-impact existence and they were truly international men of mystery to all of us. Even Google failed to provide enlightenment. “William D. Addison”, for instance, yields 18,800 hits suggesting that Bill clearly has multiple personae. So I was forced to go directly to the source and ask Bill and Greg themselves to give some pertinent information. Here are their abridged autobiographies.
Bill Addison was born at an undisclosed location on April 27, 1939. His lifelong fascination and love of nature was instilled at an early age by his parents through many outdoor activities and their encouragement to not only enjoy nature but understand what he was experiencing in the outdoors. Bill’s formal education was at the University of Toronto where he received a B.Sc. in forestry in 1963 and M.Sc. in fish physiology in 1966. Bill married his wife, Wendy, in 1966 and promptly treated her to a long honeymoon wilderness adventure in a remote corner of the Northwest Territories. Bill’s early career was with the Ontario Department of Lands and Forests as a walleye research biologist. In 1970 he began his 28 year career as a science teacher as Westgate High School in Thunder Bay.
Greg Brumpton was born in Windsor, Ontario on July 16, 1941. His family’s business in horticulture lead to an interest in agriculture and biology and Greg received his undergraduate degree in agriculture from the Ontario Agricultural College in Guelph, Ontario. He then studied at the University of Wisconsin-Madison, where he received his M.S. degree in entomology in 1966. Greg became a high school teacher in Windsor, Ontario in 1966 and married his wife, Carol Ann, in 1968. In 1970 Greg and Carol Ann moved to Thunder Bay and Greg continued his science teaching career at Westgate High School, arriving coincident with Bill Addison, thus beginning their lifelong collegial partnership. Greg, like Bill, retired in 1998 and the two soon took up their hobby of revolutionizing our understanding of the Paleoproterozoic history of the Lake Superior region.
The discovery by Bill and Greg of the ejecta-bearing bed produced by the Sudbury impact, documented in their Geology paper in 2005, was a revelation to many of us with long experience in the geology of the Lake Superior region, as well as to the broader community of impact geologists. But it was a quiet labor of dedication and perseverance by our two medalists that spanned more than a decade of frustrations and false leads before their ultimate success and their sudden appearance in our midst with their remarkable discovery. Greg became interested in the topic of impact-induced mass extinctions in the 1980’s and by 1991 had recognized that, in the Thunder Bay area, the highly fossiliferous Gunflint Formation was overlain by the nonfossiliferous Rove Formation and that the Gunflint/Rove boundary might be the same age as the Sudbury impact. He proposed therefore to examine that boundary for signs of ejecta and a possible mass extinction event. The hunt proved more difficult than it might have seemed because of sparse exposures and few drill holes to provide samples from the critical horizon. But perseverance ultimately paid off with discoveries of ejecta both in outcrop and drill cores.
You may have noticed that I have not mentioned the word “geology” anywhere in Bill’s and Greg’s professional training or experience. This is not an oversight. These two remarkable gentlemen are entirely self taught in our field of research. Their curiosity and intellectual enthusiasm have brought them to a level of geologic knowledge such that even close colleagues might not realize this lack of formal training were it not for their modesty in frequently pointing out this “flaw” in their backgrounds. I believe that never in the history of ILSG have two self-taught individuals had such a profound impact on understanding the geologic history of the Lake Superior region or stimulated as much new research as our two medalists have done.
It was my honor to have nominated Bill Addison and Greg Brumpton for the 2010 Goldich Medal. But I also would like to acknowledge the strong support of that nomination provided by Klaus Schulz and Laurel Woodruff of the USGS, Phil Fralick of Lakehead University, John Klasner of Marquette, Michigan, Jorma Kalliokoski of Houghton, Michigan, David Kring of the Lunar and Planetary Institute in Houston, Texas, and Bevan French, of NASA (retired) and scientist emeritus at the Smithsonian Institution Museum of Natural History in Washington, DC. On behalf of these supporters, and with great personal pleasure, I congratulate William D. Addison and Gregory R. Brumpton as recipients of the Goldich Medal of the Institute on Lake Superior Geology.
William F. Cannon
2010 ILSG Goldich Acceptance
Like many of you here we are both naturalists, which is to say we are both fascinated by the story of Earth and the story of how life evolved and interacts on Earth. We count ourselves fortunate to have lived through the development of plate tectonics, surely the most exciting period in the science of geology. Well we remember the late 1960s and the1970s when it seemed every second or third issue of Scientific American announced some new development in the Theory of Plate Tectonics. Geological processes started to make sense to us laymen. At this time catastrophism also reentered the geological lexicon under the impetus of Preston Cloud, Kenneth Hsu and culminating with Walter Alvarez et al proposing in 1980 that the Cretaceous-Paleogene extinction was caused by a meteorite impact, creating one of the great geological ruckuses of all time. Not to be left out of all this two paleontologists, Niles Eldridge and Stephen Jay Gould added the concept of Punctuated Equilibrium to evolutionary theory. Basically they said that evolution was a slow process in which numbers of species lost is in rough equilibrium with new ones gained until a catastrophe such as an asteroid impact occurs whence the equilibrium is punctuated—they might better have said blown to smithereens. Then, using the survivors, evolution takes off at incredible speed creating new genera and thousands of species in a geological instant before settling into a new equilibrium.
This sets the stage for our Sudbury ejecta discovery.
In 1991 Greg had put the foregoing knowledge and more together when he said to me something like, ‘The Gunflint Formation is fossil rich and the overlying Rove Formation lacks fossils. Do you suppose that we could be looking at an extinction caused by the Sudbury impact?’ I was cool to the idea because the Gunflint and Rove ages then available were significantly older than the 1850 Ma accurately dated Sudbury impact but after thinking about it for a while I came around to Greg’s proposal and we started searching. As biologists, we felt that any Sudbury ejecta would be at the Rove-Gunflint boundary. Thus, we searched for the boundary first and only secondarily for ejecta. We subsequently learned that various impact geologists had searched for ejecta evidence in both the Rove and Gunflint Formations wherever they outcropped without concentrating their search for the boundary. That may explain why we succeeded and they did not.
We went out together and we also searched separately. We walked stream beds and climbed the hills, always looking for the Gunflint-Rove contact. Time and again we came home skunked, tails between our legs. We would think it out all over again and a few months to perhaps a year later we would try searching another area. Then Greg remembered that a green, iridium-rich clay layer was the marker horizon for the Cretaceous-Paleogene contact and he remembered that a green layer existed in the lower Rove Formation at Oliver Creek. We dashed out there and sure enough there was a 20 cm thick poorly consolidated green layer in the black Rove shale. We sent a sample in for iridium analyses and it came back at 1.9 ppb, a level similar to those found at the K-Pg contact. We thought we’d found it.
You also need to know that Greg is a bit introverted, at least until he gets on a telephone. One day he cold-called Wayne Goodfellow at the Geological Survey of Canada and requested some help. I would never have had the nerve to do that. Anyway, Wayne agreed to look at our green stuff. In 1993 he advised that our green layer was likely a felsic volcanic tuff. By now we had found three more similar green layers all of which argued strongly against an impact origin. Soon after, Greg cold-called Alan Hildebrand at University of Calgary and discussed the green layer. Alan advised that it was too thin to be the Sudbury ejecta. Thus Wayne and Alan become the first geologists we wish to thank for keeping us on the rails. Nonetheless, we were at an impasse. All the outcrops we had examined were negative.
In 1999 Greg took a local geology course from Mark Smyk. From Mark, Greg learned of a drill core in the Ontario Ministry of Northern Development and Mines drill core library that had something mighty strange at what looked like the Rove-Gunflint boundary. Most of the core at the contact had been destroyed in the drilling process but some accretionary lapilli had survived amongst chunks of fractured drill bit. Metro Chaschuk donated this core, MC89, to the Ministry and he has since given us full access to all his cores. We owe Metro, another non-geologist, a huge debt of thanks.
Having now seen part of the contact, we asked Mark Smyk if OMNDM had any other cores that penetrated the Rove-Gunflint contact. Yes! A Falconbridge core, PR98-1, not only penetrated it, but the core was complete across the contact. Mark was intrigued by our wildcat idea and he turned the pertinent core boxes over to us. Now what?
We knew we had to find the definitive signature of an impact, namely planar deformation features (PDFs) in quartz grains but we had no real idea how to do this. Greg knew Steve Kissin, who was then, and is now again, Chairman of the Lakehead University (LU) Geology Department. We biologists explained our crazy idea and Steve, to his great credit, listened and did not dismiss us. He told us we had to find PDFs and we told him we had no idea how to do that. Steve volunteered to make us thin sections and about six weeks later he presented them to us, sat us down at the finest microscope we had ever used, complete with film camera on top, and told us to get to work after brief instruction on a geological mic. We could see quizzical glances from department members as they wondered just what Steve had let loose in the department but a few months later we had keys to the place and were told to use whatever facilities we needed. There was a small problem in that we didn’t know what we needed but we got to work anyway. We pestered everyone from students to professors in the department with questions. We shall be forever grateful to Steve for taking us in and to Phil Fralick, Pete Hollings, Roger Mitchell, Andrew Conly, Mary Louise Hill and many students for warming to our ideas and for helping educate us, and to Lakehead University, Department of Geology for giving us the run of the place. That is generosity and cooperation writ hugely.
We found our first PDFs in the first week at the microscope and once we knew what to look for we kept finding them along with microtektites, spherules and other features common to but not exclusive to impacts. Things were looking good but we needed thin sections from other drill holes to show the aerial extent of the debrisites. Thus we met Anne Hammond, LU’s preparator of fine thin sections and an Anne-of-many-trades. She set to work and proceeded to provide us with a steady stream of thin sections over the next few years. We would be nowhere without her and it is a pleasure to announce that Anne has just received LU’s employee of the year award, in small part because of the thin sections she prepared for us. The award could not have gone to a nicer or more deserving person.
When we started our work we both were searching the LU library for everything on impacts. Without us ever discussing it, Greg gradually took over keeping up with literature, a task he retains to this day.
We attended our first ILSG meeting in Thunder Bay in 2000. We had never experienced a professional organization like it. Instead of competitiveness we found collegiality, instead of cold shoulders we found warm people who soon were friends and we found people who seemed to relish answering the most basic questions. We felt so comfortable that we verbally announced what we thought we had found at that meeting. You ILSG members are absolutely unique in our experience and we thank you from the bottom of our hearts for helping us in so many ways. Bruce Simonson was the dinner speaker at ILSG 2000 and he introduced everyone to a variety of impact ejecta features, notably spherules. This was an immense help to us.
Also at ILSG 2000, Jon North presented his work on nickel-bearing deposits just north of Pigeon River in Ontario and concluded by offering his drill cores to anyone interested in them. We contacted him immediately and sure enough core BP99-2 had ejecta and was complete through the contact. Like the other two cores, accretionary lapilli were the key characteristic feature. Now we knew that all we had to do was to look for accretionary lapilli to identify the impact debrisites. Little did we know that we were about to get a real world geological education.
We identified PDFs from cores PR98-1 and BP99-2 so now we had impact debrisites covering several hundred square kilometres which still says nothing about it being Sudbury ejecta. We needed to show it covering a much larger area. At ILSG 2003 in Iron Mountain we asked Dick Ojakangas if he knew of any Minnesota outcrops showing the Virginia-Biwabik contact and he did not. However, he had heard of three new BHP drill cores which had been acquired by the Minnesota Department of Natural Resources drill core library at Hibbing. Dick being the wonderful warm person that he is, not only offered to introduce us to Rick Ruhanen at Hibbing, but Dick drove us there to see the cores that Rick had already laid out for us. We stood there dumbfounded; there were no accretionary lapilli and therefore no ejecta. We searched the appropriate core boxes in vain. Finally Dick said “this zone here looks a little different”. It was and it turned out to contain ejecta once we had thin sections made from samples provided by Rick. Again we were rescued by real geologists. We have since learned that more of the debrisites are missing accretionary lapilli than contain them. Some things are only learned the hard way, with expert help.
We greenhorns now had quite a body of evidence supporting an impact origin for the debrisites, however we were very unsure of our interpretations. We had a chance to meet John Spray, University of New Brunswick, in Sudbury in August, 2003. He looked at our evidence and assured us that we indeed had ejecta, just when we needed that encouragement the most.
However, to really pin our find on the Sudbury impact we knew we had to constrain its age to either side of the 1850 Ma Sudbury impact. We were able to find a ready supply of zircons in those green Rove tuffs just six metres above the top of the debrisites. Phil Fralick asked Don Davis of the Jack Satterly Geochronology Lab at University of Toronto if he could do a date for us and Don agreed to work on it when he had a chance between his regular contracts. When we hadn’t heard from Don in a year we assumed he didn’t have the time. Assumptions can be dangerous. Meanwhile Steve had met Daniela Vallini at the 2002 GAC-MAC meeting in Saskatoon, Saskatchewan. She was working with Bill Cannon on xenotime dating in the iron formations south of Lake Superior. Steve suggested e-mailing her to see if she would be interested in dating some of our samples. She replied with an enthusiastic yes, so we shipped her zircons from the same core location as Don’s. Months later, and within days of each other, both Don and Daniela sent back dates that overlapped within the limits of error. Fortunately both were forgiving of our assumption and agreed to co-publish the results with us. Thus we had the rare privilege of having dates for the tuff immediately above the ejecta-bearing debrisites confirmed by two differing methods by two very respectable labs. Daniela later agreed to date zircons from tuffs in a similar position in the Virginia Formation. All three sets of dates came in around 1832 Ma with overlapping errors, somewhat younger than the Sudbury impact, just as they should have above a Sudbury ejecta-bearing layer. Earlier Phil Fralick, Don Davis and Steve Kissin had got a date of 1878 Ma for a tuff in the Gunflint Formation. Thus, the ejecta were deposited between tuffs with dates older and younger than the Sudbury impact.
The other thing you need to know is that Greg is not a quitter and he literally leaves no stone unturned. While I worked on our discovery paper Greg was spending time wandering the bush and now that he knew what to look for he began turning up small ejecta-bearing outcrops. In fact, Greg found most of the outcrops that we now know of in the Thunder Bay area.
I can not close without thanking my family, especially Carol Ann, my wife. Her encouragement and patience over the decades has been a wonderful gift. Our sons Grant and Aaron have cheerfully listened to my frequent pronouncements on our findings. The support from all of them has kept me going.
As we look back we have learned that, in the words of A. C. Grayling, “Science is the outcome of being prepared to live without certainty… It embraces doubts and loose ends.” We hope that we have tied up one small Lake Superior geology loose end. So many more still need tying.
Thus, we accept this award on behalf of all of you who have helped us. We would never have gotten here without you. It is as much yours as it is ours. Thank you!