(no subject)
In the photograph above, a portion of cliff about 30 feet high is shown.
From what location in the Grand Canyon did Dr. Alley take this image?
E. Near the bottom, where the river has cut through rocks that were cooked, squeezed, and partially melted deep in an old mountain range.
This is the Vishnu Schist and Zoroaster Granite, rocks from the heart of a mountain range. The river is just barely out of the picture to the bottom.
Right Points Earned: 1/1
Correct Answer: E
Your Response: E
Geological evidence based on several radiometric techniques has provided a scientifically well-accepted age for the Earth. Represent that age of the Earth as the 100-yard length of a football field, and any time interval can be represented as some distance on the field. (So something that lasted one-tenth of the age of the Earth would be ten yards, and something that lasted one-half of the age of the Earth would be fifty yards.) On this scale, how long have you personally been alive?
A. Much less than the thickness of a sheet of paper.
If the 4.6 billion years of Earth history are 100 yards, then the few thousand years of written history are just one-millionth of that history, just over the thickness of a sheet of paper. And your small piece of written history must be only a small fraction of a sheet of paper, roughly 1/200th or so.
Right Points Earned: 1/1
Correct Answer: A
Your Response: A
One practical radioactive system used to date lava flows involves:
A. The solid potassium-40, which decays to the gas argon-40.
Potassium-40 is common in solid minerals, and decays to produce the gas argon-40. And despite his great contributions to humanity, no one has named an isotope after Penn State’s president.
4.
In age dating, geologists use:
C. Radiometric techniques and layer-counting for absolute dating of events that happened in the last 100,000 years, and other radiometric techniques for absolute dating of much older events.
Points Earned: 0/1
5. Using only uniformitarian calculations from the thickness of known sedimentary rocks, likely rates at which those rocks accumulated, and features in and under those sedimentary rocks, geologists working two to three hundred years ago estimated that the Earth:
C. Is more than about one-hundred-million years old.
Radiometric techniques reveal the Earth to be about 4.6 billion years old, but early geologists did not have the sophisticated instruments to measure the trace radioactive elements and their offspring. Working from the rocks, the geologists knew that the age must be in the neighborhood of 100 million years, plus extra time in unconformities and additional extra time in the oldest, metamorphic rocks.
Correct Answer: C
From what location in the Grand Canyon did Dr. Alley take this image?
E. Near the bottom, where the river has cut through rocks that were cooked, squeezed, and partially melted deep in an old mountain range.
This is the Vishnu Schist and Zoroaster Granite, rocks from the heart of a mountain range. The river is just barely out of the picture to the bottom.
Right Points Earned: 1/1
Correct Answer: E
Your Response: E
Geological evidence based on several radiometric techniques has provided a scientifically well-accepted age for the Earth. Represent that age of the Earth as the 100-yard length of a football field, and any time interval can be represented as some distance on the field. (So something that lasted one-tenth of the age of the Earth would be ten yards, and something that lasted one-half of the age of the Earth would be fifty yards.) On this scale, how long have you personally been alive?
A. Much less than the thickness of a sheet of paper.
If the 4.6 billion years of Earth history are 100 yards, then the few thousand years of written history are just one-millionth of that history, just over the thickness of a sheet of paper. And your small piece of written history must be only a small fraction of a sheet of paper, roughly 1/200th or so.
Right Points Earned: 1/1
Correct Answer: A
Your Response: A
One practical radioactive system used to date lava flows involves:
A. The solid potassium-40, which decays to the gas argon-40.
Potassium-40 is common in solid minerals, and decays to produce the gas argon-40. And despite his great contributions to humanity, no one has named an isotope after Penn State’s president.
4.
In age dating, geologists use:
C. Radiometric techniques and layer-counting for absolute dating of events that happened in the last 100,000 years, and other radiometric techniques for absolute dating of much older events.
Points Earned: 0/1
5. Using only uniformitarian calculations from the thickness of known sedimentary rocks, likely rates at which those rocks accumulated, and features in and under those sedimentary rocks, geologists working two to three hundred years ago estimated that the Earth:
C. Is more than about one-hundred-million years old.
Radiometric techniques reveal the Earth to be about 4.6 billion years old, but early geologists did not have the sophisticated instruments to measure the trace radioactive elements and their offspring. Working from the rocks, the geologists knew that the age must be in the neighborhood of 100 million years, plus extra time in unconformities and additional extra time in the oldest, metamorphic rocks.
Correct Answer: C