In the Last Few Years Improvements in Technology Have Allowed

question 6

Multiple Choice

In the last few years improvements in technology have allowed geologists to date single grains of some minerals in rocks.A geologist separates 5 grains of the mineral zircon,which can be dated by the Uranium-lead method,and the crystal retains parent and daughter through weathering,erosion,and deposition.Thus,dating each mineral grain only gives the age of the source rock that was eroded,to produce that sand,from which the zircon grain is derived.The 5 grains yield ages of 160,110,2020,66,and 162 million years.What do these ages tell you about the age of the sedimentary strata?

• A)They are Precambrian rocks,older than 2020 million years.
• B)They are between 160 and 162 million years.
• C)They are younger than 66 million years.
• D)There are no age constraints from this data; sedimentary rocks cannot be dated by geochronology.

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Definitions:

Brightness

A visual perception describing how luminous or vivid a light source or color appears to be.

Trichromatic Theory

A theory of color vision based on the existence of three types of cones in the retina that are most sensitive to blue, green, or red light.

Nobel Prize

A set of international awards given annually in several categories such as Physics, Chemistry, Medicine, Literature, and Peace, to individuals or organizations who have made significant contributions to humanity.

Wavelength

The distance between successive crests of a wave, especially points in a sound wave or electromagnetic wave, which is related to the wave's frequency and energy.