The continental Redbeds of soil in South AFRICA was aged by 1.9 billion years indicate that the atmospheric Oxygen at that time was that of the modern level A- 15 perecent B- 30 percent C- 70 percent D- 25 percent
Question
The continental Redbeds of soil in South AFRICA was aged by 1.9 billion years indicate that the atmospheric Oxygen at that time was that of the modern level A- 15 perecent B- 30 percent C- 70 percent D- 25 percent
Solution
The answer is B- 30 percent. The red beds are sedimentary rocks, which were formed in the presence of oxygen. The presence of red beds dating back 1.9 billion years suggests that the level of oxygen in the atmosphere at that time was close to current levels. Current atmospheric oxygen levels are about 21%, but in this context, the closest answer is 30%.
Similar Questions
The Atmospheric Oxygen at 1.9 billion years ago, was percent that of the modern level. A- 10% B- 15% C- 70% D- 50%
What type of terrestrial sediments began to form as atmospheric oxygen level rose late in the Proterozoic? A- Black shale B- Oolitic limestone C- Chert D- Redbeds of soil
Chose the correct statement(s)(a) A very thin envelope of gases that surrounded the earth at the time of its formation.(b) About 600 billion years ago plants and animals were formed on the Earth.(c) The two probable sources of oxygen in the atmosphere are photodissociation of watermolecule and evapotranspiration.(d) The evidence of oxygen in the ocean is noted between 2.5 and 3.0 billion years ago.(a) and (b)(b) and (c)(c) and (d)(a) and (d)
How did Earth's atmosphere become oxygen-rich?A.Biological activityB.Volcanic outgassingC.Ozone depletionD.Tectonic movementSUBMITarrow_backPREVIOUS
When the Earth was first formed there was no oxygen in the atmosphere.Explain how the atmosphere changed so that today it is 21% oxygen and only 0.04% carbon dioxide.
Upgrade your grade with Knowee
Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.