How have scientists used isotopic analysis to determine the rise of atmospheric CO2 is mostly from the burning of fossil fuels?
A) Since 14C is an unstable isotope, scientists have dated the atmospheric carbon to the period since the Industrial Revolution.
B) Both coal and oil contain a high proportion of 14C. By analyzing, 14C/12C ratios, scientists have been able to determine the source based on this fact.
C) The low proportions of 13C and 14C within atmospheric CO2 indicates the source is fossil carbon.
D) 14C concentrations are much higher in urban areas than in rural areas, indicating fossil fuels must have a higher 14C/12C ratio than carbon from other sources.
C
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Which of the following describes the Maunder Minimum?
A. It occurred during the Little Ice Age. B. There were many sunspots. C. It caused a significant change in the eccentricity of Earth's orbit. D. It has been studied by analysis of ice cores in Antarctica.
A gneiss containing kyanite and sillimanite most likely formed from a metamorphosed
A) limestone. B) mafic igneous rock. C) coal. D) shale.
Hot springs and geysers release hot water to the Earth's surface. This water may have been heated by residing which location?
a. Very deep in the crust b. The proximity of a magma chamber c. Near a mountain river d. All of the above e. Both a and b
What combination of factors was responsible for the disaster west of Yellowstone National Park on August 17, 1959?
A) Rock falls filled a lake with debris until the water overtopped the dam and eroded through the concrete. B) Water migrating along foliation layers in the metamorphic rock destabilized a dam, which collapsed and flooded the valley. C) A severe earthquake triggered a slide that blocked a river and flooded a campground. D) Drainage from the reservoir generated a lahar, which destroyed small towns downstream.