Who first proposed that the dinosaurs were dealt a death blow from space?
it's for my homework due tomorrow and i really don't know this answer.
you may think it's the Alvarez's but they were the second ones to figure it out, not the first.
- HoratioLv 71 decade agoFavorite Answer
The following people are possible candidates
- In 1891, geologist Grove Karl Gilbert theorized that the large crater near Flagstaff Arizona was caused by either a meteor or gas explosion (but no mention of dinosaur extinction)
- In 1905, geologist Daniel Barringer supposedly confirmed that the Arizona crater had to be the result of a meteor and nothing else (but no mention of dinosaur extinction).
- In 1960, astrogeologist Dr. Eugene Shoemaker conclusively proved that the Arizona crater was created by a meteor impact. And although he proved how meteor impacts can cause sudden geologic changes, there is no direct mention of dinosaur extinction.
- In 1980, physicist Luis Alvarez, his son, geologist Walter Alvarez, and nuclear chemists Frank Asaro and Helen V. Michael from the University of California, Berkeley discovered unusually high concentrations of iridium in a specific layer of rock strata in the Earth's crust. Iridium is an element that is rare on Earth but relatively abundant in many meteorites. From the amount and distribution of iridium present in the 65 million year old "iridium layer", the Alvarez team later estimated that an asteroid of 10–14 kilometers must have collided with the earth. This led to the creation of the asteroid-impact theory which tried explain the extinction of the dinosaurs.
What source of yours claims the Alvarez's were not the first?Source(s): http://en.wikipedia.org/wiki/Impact_event http://en.wikipedia.org/wiki/Daniel_Barringer_(geo... http://en.wikipedia.org/wiki/Eugene_Shoemaker