Documents about Oxygen Isotope

  • 2 Pages

    geol1020hw4

    Colorado, GEOL 1020

    Excerpt: ... Homework #4, Geol 1020, Spring 2008 1. Which of the following is NOT geologic evidence for glaciation and/or climate change in the Pleistocene? A. oxygen isotope s in marine shells B. unsorted and unlayerd conglomerates (tills) C. pollen in lake sediments D. abundance of gasses in ice cores E. all of the above are evidence for glaciation and/or climate change solar 2. Fill in the blank with one word - The earth's climate is an engine driven by _ energy. 3. Why does the oxygen isotopic ratio of seawater change in a glacial period relative to a non-glacial period? A. the 16O isotope of oxygen selectively concentrates in the oceans when glacial ice sheets are growing B. the 18O isotope of oxygen selectively concentrates in the oceans when glacial ice sheets are growing C. the 18O isotope of oxygen selectively concentrates in ice when glacial ice sheets are growing C. the 18O isotope of oxygen selectively concentrates in ice when glacial ice sheets are melting 4. When geologists work with the is ...

  • 2 Pages

    geo hw 4

    Colorado, GEOL 1020

    Excerpt: ... Homework #4, Geol 1020, Spring 2008 1. Which of the following is NOT geologic evidence for glaciation and/or climate change in the Pleistocene? A. oxygen isotope s in marine shells B. unsorted and unlayerd conglomerates (tills) C. pollen in lake sediments D. abundance of gasses in ice cores E. all of the above are evidence for glaciation and/or climate change 2. Fill in the blank with one word - The earth's climate is an engine driven by _SOLAR_ energy. 3. Why does the oxygen isotopic ratio of seawater change in a glacial period relative to a non-glacial period? A. the 16O isotope of oxygen selectively concentrates in the oceans when glacial ice sheets are growing B. the 18O isotope of oxygen selectively concentrates in the oceans when glacial ice sheets are growing C. the 18O isotope of oxygen selectively concentrates in ice when glacial ice sheets are growing C. the 18O isotope of oxygen selectively concentrates in ice when glacial ice sheets are melting 4. When geologists work with the isotope ...

  • 1 Pages

    GEO302C-L28

    University of Texas, GEO 302C

    Excerpt: ... GEO302C 03/31/08 Lecture 28: Millennial Changes: Delta 18O in Ice Sheets Homework Definitions Dates Important People 1. Climate change at different time scales a. Tectonic: longest scale- hundreds of millions of years b. Orbital: tens to hundreds of thousands of years- cycles c. Millennial: thousands of years- oscillations 2. Oscillations recorded in Greenland Ice Cores a. Delta18O and dust help to date ice b. Early studies in 1970 c. Lots of dust mean climate was windier and more polluted d. Underlying trend of graduate glacial- interglacial changes 3. Millennial Oscillations a. Younger Dryas- during the last deglaciation i. 1500 yrs long ii. Abrupt beginnings and endings (about 10 yrs) b. Millennial Oscillations during glacial period vs. interglacial i. Very wide spacing and amplitude ii. Average spacing: 1500 yrs iii. Called Dansgaard-Oeschger cycles 4. Oxygen isotope ratios in Ice and Ocean Cores a. Ocean Cores i. D18O signals 2 influences: Temp. Change and Ice volume b. Ice cores i. D18O signals refl ...