What are index minerals, and what are they used for? Give an example of minerals that would be
found in a low-grade, intermediate, and high-grade metamorphosed shale. What will be an ideal response?
Index minerals are minerals that are known to form only within specific temperature and pressure
ranges. Their presence allows geologists to establish the metamorphic grade of a rock because the
highest-grade mineral indicates the temperature and pressure the rock was at for some time. Low-grade
minerals include chlorite, muscovite, and biotite; intermediate include muscovite, biotite, garnet,
staurolite, and kyanite; and sillimanite indicates high grade
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The banning of TV set and computer disposal in landfills by 35 states in the U.S. is expected to
a. cause interstate smuggling of e-waste b. be regulated by the federal government c. be voted down by consumers during the next general election d. set the stage for an emerging highly profitable e-recycling industry e. none of these answers
Which of the following correctly describes satellites?
A) They are DNA molecules in which long nucleotide sequences are repeated a few times. B) They are DNA molecules in which long nucleotide sequences are repeated many times. C) They are DNA molecules in which short nucleotide sequences are repeated a few times. D) They are DNA molecules in which short nucleotide sequences are repeated many times.
Which form of chemical weathering specifically affects the iron contained in ferromagnesian, rock-forming, silicate minerals?
What will be an ideal response?
The urban heat island steepens the environmental lapse rate, creating unstable conditions by
A) greatly heating the ground surface with less heating further up in the atmosphere. B) greatly heating the ground surface and greatly heating the atmosphere further up. C) greatly cooling the ground surface with great heating further up in the atmosphere. D) greatly cooling the ground surface and greatly heating the atmosphere further up.