How many ice ages do scientist estimate have occurred during the last billion years?
3
5*************************************
6
7
How often do scientists say that recent cycles of advancing and retreating ice sheets occur?
approximately every 100,000 years*******
approximately every 50,000 years
approximately every 10,000 years
approximately every 1,000 years
Which is faster: the advance or the retreat of an ice sheet?
The advance of an ice sheet is faster
The retreat of an ice sheet is faster*********************************
Which of the following is NOT considered geologic evidence of past ice ages?
Glacial till and erratics
Loess
Ice shelves****************************
rock striations
Which of the following is NOT believed to be a cause of ice ages?
Changes in the orbit of the earth around the sun*****************************
Changes in the positions of the continents
Changes in volcanic
Variations in the energy output of the sun
Answers:
1.B
2.A
3.B
4.C
5.A
Thank You.
1.B
2.A
3.B
4.C
5.A
6.D
7.True
8.True
9.True
10.False
1. B - 5
2. A - approximately every 100,000 years
3. B - The retreat of an ice sheet is faster.
4. C - ice shelves
5. A - Changes in the orbit of the Earth around the Sun
6. D - Steppe
7. A - True
8. A - True
9. A - True
10. B - False