EOSC 114 Chapter Notes - Chapter 32-34: Tektite, Extinction Event, Oort Cloud
27 Aug 2017
School
Department
Course
Professor
Document Summary
A huge portion of our time is not available in the rock record. Mass extinction which there is a ceasing of existence of a wide range of species from a wide range of environment and locations: must be short and sudden. Even though there was a huge devastation on the earth, there was still a huge percentage of species that survived (rodents and small animals) Clay is a type of rock that has very fine components. At k-pg. boundaries, there is huge spike of iridium and influx of material from outer space same time period as dinosaur extinction: biggest single source of iridium on earth"s surface: comets and meteors. Evidence of a large impact: ferns spores are activated by fires e. g. forest fire. Any spike in the fern spores tells us that it has just been through forest fires: soot could be burnt organic matters. Because of wind and water erosion, much of these craters get covered up.
