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Home / Science / Professor Emeritus Samuel Bowring, a pioneering geologist and geochronologist, dies at the age of 65

Professor Emeritus Samuel Bowring, a pioneering geologist and geochronologist, dies at the age of 65



Professor Emeritus Samuel A. Bowring, a longtime MIT professor of geology, died on July 17 at the age of 65.

Bowring was recognized for his exceptional field geologist and innovation in uranium-lead isotope geochronology. Achieve unprecedented analytical precision and accuracy in calibrating the geological dataset and reconstructing the co-evolution of life and solid earth.

No data, no quotas

A popular aphorism: "No data, no quotas". appeared in many talks and conversations by Bowring – that is, to fully understand the past events contained in the rock record, one has to understand their timing. One of his earliest major contributions that changed the geologist's knowledge of Earth's early development was his work in the 1

980s at the Acasta Gneiss Complex, a rock formation in northwestern Canada that represses the date of the oldest known rocks 4, 03 billion years. The granite samples he collected from an outcrop on an island in the remote Acasta Basin proved to be rare remnants of the earliest earth crust.

"What matters more to the Acasta gneiss complex than its 4.03 billion year old age is its character that Sam recognized and documented," said Paul Hoffman, emeritus professor of geology at Harvard University Sturgis Hooper and longtime Bowring employee friend. Hoffman explains that the Acasta rock, coupled with Bowring's endorsement, has fundamentally changed the geologists' understanding of continental formation. Prior to Bowring's work, the prevailing view was that continents had grown steadily over geological time. However, with these ancient gneiss samples, Bowring has been able to characterize a complex history that precedes its crystallization, pointing instead to a process of progressive "recycling" of the crust – where rock near the surface of the earth is transmitted through the mechanisms of plate tectonics the convection currents of the mantle are subsumed and transformed. Hoffman said, "Sam's fascination for the creation and maintenance of the Continental Crust has never left him, be it on Great Bear Lake, the Grand Canyon or the High Cascades in Washington State."

Beyond the Investigation of Physical Processes Forming In the lithosphere, Bowring also sought to understand those who form the biosphere. His work on pre-Cambrian / Cambrian sediment layers determined the timing and speed of the key biological event known as the Cambrian explosion, which began almost 540 million years ago. He was able to show that the Early Cambrian period, which saw the most dramatic explosion of evolutionary activity and animal diversity – including the first appearance of chordates, brachiopods, and arthropods – lasted no more than 10 to 50 million years, as anticipated. but lasted only 5 to 6 million years.

Long-time friend and colleague Tim Grove, the Robert R. Shrock Professor of Earth and Planetary Sciences at MIT, wrote about the achievement in a quote for the American Geophysical Union when Bowring was honored with the Walter H. Bucher Medal in 2016: "Sam has shown that in this short period of time, more Phyla have emerged than ever before existed on Earth. This is a truly profound and amazing new discovery of how life on Earth has evolved. "

Bowring also determined the timing and duration of what became known as" the great dying ": the largest of the earth's five great mass extinctions. This was the end of the Permian period and the elimination of over 96% of the marine species and about 70% of the species on land. The rocks collected by Bowring and employees from sites across China across the Permanent-Triassic border showed that the ecological collapse was taking place at breakneck speed – in less than 30,000 years, at a rate many times faster than previous estimates was – and without warning in geological terms.

A world expert in uranium-lead isotope dating, Bowring began to see in 2002 what he later described as the "double-edged sword of high-precision geochronology". in addition to the resolution and the quantitative stratigraphic analyzes, many new techniques developed. He recognized that without calibration and intercalibration of the methods for dating radioisotopes and quantitative chronostratigraphy, their accuracy and ability as individual tools to understand depth-of-time were compromised. In response, he and his colleague Doug Erwin conceived the EARTHTIME initiative, a community-based initiative to promote inter-disciplinary collaboration and eliminate bias between laboratories and techniques. Bowring's refusal to "check our ego at the door" reflected his unwavering goal to take the accuracy of geochronology to a new level, and helped the initiative to reach consensus and develop best practices and protocols. EARTHTIME continues to lead international workshops that go beyond calibration and standardization to address the broader geoscientific community and seeks to understand the rock record in ever more refined and differentiated ways.

"When the Art of Geochronology Is the Rendering of Data In its geological context, Sam is our Michelangelo," said MIT's former department head for Earth, Atmospheric and Planetary Sciences (EAPS) and close friends and colleague Tom Jordan about Bowring , "He has always insisted that it is just as important to know who you are with and why, how to set the date yourself. that the precision of absolute dating is strongest when samples can be precisely placed in sections. "

Bowring's interest in using tracer isotopes to study terrestrial systems has also spread to her usefulness in tracking environmental contaminants. In his laboratory, methods have been developed to not only detect naturally occurring sources and to determine natural regional baselines, but also to document variations that correlate with anthropogenic inputs related to urbanization and industrialization.

A dedicated teacher and mentor

Bowring joined the faculty of EAPS at MIT in 1991, where he not only promoted the careers of more than two dozen postgraduates and postdocs, but also developed his professional commitment to promoting the Basic training proved. Bowring was a freshman adviser to undergraduate and freshman students for over 20 years and was named a Margaret MacVicar Faculty Fellow in 2006 by the Institute's program. The institute pays tribute to exemplary and sustainable contributions to teaching and training of students at MIT. In 2007, he received the MIT Everett Moore Baker Memorial Award for outstanding achievements in basic education. He was also instrumental in shaping the curriculum and was a member of the MIT Curriculum Committee from 2007-2010. He was also Chairman of the EAPS. He studied Geology and Geochemistry from 1999 to 2002 and was Chairman of the EAPS Research Training Group until 2015. As a field geologist, he was keen to lure students to out-of-school locations and conduct annual trips to the US Field, which was scheduled in the department's calendar – from West Massachusetts to Yellowstone to the Las Vegas desert.

"Sam has been an exceptional case of an effective and dedicated pedagogue for undergraduate courses that has gone far beyond EAPS and our students," recalls Grove. "He has received more undergraduate education over the past 25 years than any other member of our department, and was deeply committed to the importance of basic student education in this area – giving students hands-on experience and using real geology to inspire and teach them basics. "

Bowring also played a key role in the leadership of Terrascope, a first-year learning community that was launched in 2002 by EAPS and the Department of Civil and Environmental Engineering. Bowring became Deputy Program Director Director from 2008 to 2015 in 2006. The nationally recognized program, which has been the subject of several academic papers and has become one of MIT's largest first-year communities, challenges students with diverse research interests to address complex, global issues to tackle sustainability. Climate and the Earth system in a series of team-oriented, student-driven classes. In 2013, Bowring and his co-authors described the innovative curriculum by saying, "Our focus is on using a multidisciplinary approach to show that understanding earth science is important to students' outlook, whether they know it or not. We believe that it is our responsibility to teach as many disciples as possible about the Earth system, and in our experience, Terrascope students have a greatly expanded awareness of the effects of the earth and man on it. "

Born in Portsmouth, New Hampshire. On September 27, 1953, Bowring grew up in Durham, New Hampshire, where he later attended the University of New Hampshire. After graduating in geology in 1976, he studied at the New Mexico Institute of Mining and Technology, where he graduated in 1980.

Bowring had an early opportunity at the University of Kansas to collaborate with supervisor Randall Van Schmus on a project in the Northwest Territories of Canada (NWT) where he was introduced to Hoffman for the first time. This laid the foundation for the PhD and continuing his studies in the NWT's Proterozozoic Wopmay, after he joined the faculty in 1984 at Washington University in St. Louis (WU). As Assistant Professor at WU, Bowring and Ian Williams of the Australian National University analyzed the region's Acasta gneiss.

In addition, the Emeritus Robert R. Schrock – Professor of Geology Bowring was named a member of the National Academy of Sciences and the American Academy for Advancement of Science appointed the American Geophysical Union and was nominated by the organization with both the Norman L. Bowen Award also awarded the Walter H. Bucher Medal. He was also a member of the Geochemical Society and the Geological Society of America.

His wife, Kristine M. (Fox) Bowring, two stepdaughters, Kelley Kintner and Sara Henrick, as well as he survived his siblings James Bowring, Joseph Bowring and Margaret Ann Bowring-Price. At the request of the family, no formal services are provided.


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