{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

09 GEOS 1004 - GEOS 1004 SPOTILA Lecture 8 Geologic...

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
GEOS 1004, SPOTILA Lecture 8, 9/22/09 Geologic principles II: the rock record and geologic time *One of the most important contributions of geoscience has been discovering the age and history of the earth. It is as important as the discovery that the sun is the center of the solar system, or that the universe extends far beyond the solar system. Age of Earth = 4.6 billion years (4.6 Byr = 4.6 Ga = 4,600,000,000 = 4.6x10 9 yrs) *What is this based on? Dated by a meteorite geologic timescale = -variable resolution, eons, eras, periods, epochs -resolution decreases back in time (more divisions towards the present) WHY? -terminology is based on original timescale which was relative WHY? Relative geologic time Sequence of events based on the record preserved in the rocks; not ages in years. Rules to establish a sequence: 1) superposition -stack of sedimentary layers -oldest on the bottom, youngest on top -what is another word for the layers? 1b) fossils 2) Original horizontality = sedimentary layers were deposited nearly flat (if warped, tilted, cut, this
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern