Gerta Keller

Gerta Keller
Born 7 March 1945
Schaan, Liechtenstein
Alma mater San Francisco State University (B.S., 1973)
Stanford University (Ph.D., 1978)

Gerta Keller (born 1945) is a paleontologist who contests the Chicxulub crater as the location of the meteorite impact, postulated as the cause of the Cretaceous–Tertiary extinction event 65 million years ago by the Alvarez hypothesis. Keller is currently a professor of Geosciences at Princeton University.[1]

Contents

Biography

Early life and education

Keller was raised in Switzerland on a dairy farm, the sixth of 12 children. She grew up in poverty; the unheated room in which she shared a bed with her sister who grew icicles inside the room during the winter. In the one-room schoolhouse where she was educated, boys were given training in math and science while girls were taught cooking and cleaning, the skills they would need to be proper housewives. Her hunger for knowledge led her to read the textbooks assigned to her elder siblings, and she would prepare summaries of the material for her brothers and sisters.[2]

She attended a vocational school starting at age 14 and learned sewing. There she organized a protest against rules that required female students to wear skirts, as she rode her bicycle three miles each way to school and wanted to be able to protect herself from the cold. The female students won the right to wear pants from then on.[2]

After receiving her vocational certificate at age 17, she went to work for Pierre Cardin, where she was paid the equivalent of 25 cents per hour to sew luxury gowns that would sell for as much as $1,000 for which she was paid $12. She traveled around the world, learning English and working in England, followed by travel to North Africa, Spain and Australia. She survived being shot in a bank robbery in Australia in 1965, despite awakening in a hospital intensive care unit to find a priest asking her to confess, telling her that she was going to die.[2]

After ending up in San Francisco in 1968, Keller was "freaked out" by the shots and tear gas launched at student protests; she chose to focus on education and took a high school equivalency exam. She received her undergraduate degree at San Francisco State University and received a doctorate in geology and paleontology from Stanford University in 1978.[2]

Paleontology

After earning her doctorate, Keller worked for the United States Geological Survey and Stanford.[2] She came to Princeton University in 1984 and after a few years started studying the K–T boundary, the geological signature of the Cretaceous-Tertiary extinction event.[3] Keller's research has led her to conclude that the Chicxulub impact played a major role in the demise of the dinosaurs, but that the mass extinction did not occur until 300,000 years later as the result of a second meteor impact whose impact site is unknown but may lie at the bottom of what is now the Indian Ocean (Shiva crater).[2][4] Keller's analysis of the sedimentary evidence led her to conclude that the K-T boundary layer had been laid down over a 300,000-year period, stating that "I'm sure the day after, they had a headache," but that "we vastly overestimate the damage to the environment and to life that this Chicxulub impact had" in killing off the dinosaurs.[5]

The main evidence for the Alvarez hypothesis that a single impact resulted in the Cretaceous–Tertiary extinction event that killed the dinosaurs has come from the presence around the world of shocked quartz granules, glass spherules and tektites embedded in a layer of clay with extremely high levels of iridium, all signs of an asteroid impact. Keller's research found layers where the glass spherules and the iridium clay are found separated by as much as 8 feet (2.4 m) of sandstone and other material. Supporters of the Alvarez theory believe that the sandstone is the result of a massive tsunami that sandwiched the sand from the massive waves triggered by the impact between the shocked quartz layer and the iridium clay. Keller's analysis of the strata between the spherules and iridium clay contain signs that the material was laid down over as much as 300,000 years based on signs of plankton, worms and weathering found on the intervening material.[6]

Selected publications

References

  1. ^ Staff. "Princeton Paleontologist Produces Evidence For New Theory On Dinosaur Extinction", Science Daily, September 26, 2003. Accessed June 11, 2009.
  2. ^ a b c d e f Hedges, Chris. "PUBLIC LIVES; Where Dinosaurs Roamed, She Throws Stones", The New York Times, December 17, 2003. Accessed June 11, 2009.
  3. ^ Schultz, Steven. "Dinosaur dust-up: Princeton paleontologist produces evidence for new theory on extinction", Princeton Weekly Bulletin, September 22, 2003. Accessed June 11, 2009.
  4. ^ Chatterjee, Sankar; Mehrotra, Naresh M.. "The Significance of the Contemporaneous Shiva Impact Structure and Deccan Volcanism at the KT Boundary". 2009 Portland GSA Annual Meeting (18–21 October 2009). pp. 50–9. http://gsa.confex.com/gsa/2009AM/finalprogram/abstract_160197.htm. 
  5. ^ Velasquez-Manoff, Moises. "Did Asteroids Really Do in the Dinosaurs?: Scientists Challenge the Story of How the Dinosaurs' 160-Million-Year Reign Came to an End", ABC News, May 24, 2009. Accessed June 11, 2009.
  6. ^ Lovett, Richard A. "'Dinosaur Killer' Asteroid Only One Part of New Quadruple-Whammy Theory", National Geographic, October 30, 2006. Accessed June 16, 2009.

External links