The Gulches is an area of volcanic rock that is gashed by many channel

Question

The Gulches is an area of volcanic rock that is gashed by many channels that lead downhill from the site of a prehistoric glacier to a river. The channels clearly were cut by running water. It was once accepted as fact that the cutting occurred gradually, as the glacier melted. But one geologist theorized that the channels were cut in a short time by an enormous flood. The channels do show physical evidence of having been formed quickly, but the flood theory was originally rejected because scientists knew of no natural process that could melt so much ice so quickly. Paradoxically, today the scientific community accepts the flood theory even though scientists still do not know of a process that can melt so much ice so quickly.

Which one of the following, if true, most helps to resolve the apparent paradox in the passage?

(A) Rippies, which indicate that the channels were cut by water, have been discovered in the floors of the channels.

(B) The Guiches is known to be similar in certain respects to many other volcanic rock formations.

(C) More than one glacier was present in the area during prehistoric times.

(D) Volcanic rock is more easily cut by water than are other forms of rock.

(E) Scientists now believe that the prehistoric glacier dammed a source of water, created a huge lake in the process, and then retreated.

Kurtosis · Answer

Question Type: Paradox

We have to explain why the flood theory was accepted even though scientists did not know of a process that could melt ice so quickly.

(A) Rippies, which indicate that the channels were cut by water, have been discovered in the floors of the channels. - Incorrect. The channels were cut by water, but we do not know whether the channels were cut by slow moving water or floods. Not Sufficient.

(B) The Guiches is known to be similar in certain respects to many other volcanic rock formations. - Incorrect. Irrelevant.

(C) More than one glacier was present in the area during prehistoric times. - Incorrect. Irrelevant.

(D) Volcanic rock is more easily cut by water than are other forms of rock. - Incorrect. We cannot explain the acceptance of flood theory based on this fact.

(E) Scientists now believe that the prehistoric glacier dammed a source of water, created a huge lake in the process, and then retreated. - Correct.

Answer: E

NEENA SHEREEN · Answer

is the answer E? other options doesn't seem convincing....

kunalsinghNS · Answer

Option E fits the bill !
it clearly supports the flood theory but doesn't reveal how glacier melted.

Skywalker18 · Answer

A) scientists used to not believe in the flood theory, because they didn't know how ice could melt so quickly (so as to flow down the rock so fast)

(B) scientists now believe in flood theory, even though they still don't know of a scientific process that can make ice melt so quickly.

We need an answer that helps explain why this might be.

The reason that (E) is correct is because it gives evidence to the point that the flood did occur. So, even if the scientists haven't figured out that one thing (how ice melted so quickly), it's still likely that the flood did occur and cause the ripples.

Take for example the following argument:

It used to be that people believed the sun revolved around the earth, and one reason was that no one had gone to the sun.

It is now believed that the earth revolves around the sun, even though no one has yet to go to the sun.

Notice this analogy shares a common trait with our original argument:
The evidence used before has still not been resolved, but that doesn't mean the opinion can't be changed.

(D) does not resolve the paradox because the paradox does not involve a comparison of one type of rock to another.
(C) it didn't say that these glaciers were on top of this mountain. It just said that they were "in the area". So the fact that there are more glaciers is irrelevant.

Fdambro294 · Answer

First, in all the resolve the paradox type questions, the goal is to identify the 2 ideas or facts that seem to be in contradiction.

For a long time scientists accepted that the cutting of the channels by the water occurred gradually as the glacier melted.

Then, at first, most rejected the hypothesis that the channels were quickly created by a flood because no one knew of any process that could melt so much ice so quickly.

However, in apparent contradiction to this second fact, most people NOW accept this quick flood theory even though scientists still do not know of any natural process that could melt ice that quickly.

Why is it that NOW scientists accept the flood theory, even thought they still have not determined a natural process that explains how the ice could have melted so quickly? Nothing has changed really in this regard from when they first rejected the theory. So why the sudden change of heart now?

A lot of the resolve the paradox questions revolve around determining an alternative explanation for the facts: something that would tell us how the scientists could believe the channels were created quickly by a flood, even though the ice could not have melted quick enough via a natural process to create such a flood (in their eyes).

-A- We don’t really get any new info. from answer A. We already know that water was the cause of the creation of the channels. All the Rippies do is show further evidence of a fact we already know.

We need to answer why it is scientists now believe that the channels were created quickly by a flood when there is STILL no natural process that could melt ice quick enough to create such a flood.

Eliminate A

-B- All this answer tell us is that the rock is similar to other volcanic rock. We don’t have anything from the passage to help connect this fact to anything meaningful. Just because the rock is similar to other volcanic rocks, why do the scientists now believe in the flood theory? Nothing is resolved by the fact from answer B

Eliminate B

-C- “More then one glacier was present...”

To me, this answer seemed like the “runner-up.” One could think that this new fact shows us that there was more than one glacier that could have melted. Perhaps TWO glaciers melting would explain how the flood theory could be the explanation for the creation of the channels.

However, just because there was one more glacier, the fact still stands that the scientists do not know of any natural process that could melt the ice quick enough. Are 2 glaciers enough for the scientists to reconsider this position? We just don’t know.

The fact stands that the scientists still do not know of any natural process that could have melted the ice so quickly such that the flood theory could be explained. This was their reason for rejecting the flood theory in the first place. Why did they change their mind and now accept the theory, even though no new natural processes were discovered? We just don’t know.

Eliminate C

-D- Just because this volcanic rock is cut more easily by water than is other types of rock, we still don’t know why the scientists changed the their mind and now accept the flood theory.

Eliminate D

-E- Offers an alternative explanation for why the scientists now accept the theory, even though a natural process that could have melted the ice quickly has not been discovered. All the facts remain true and the apparent contradiction is resolved.

What this answer offers is another pathway or method via which the water could have flooded the rock quick enough to create the channels. If the glacier dammed off a huge source of water, then it is possible that this water built up considerably over the years. If this dam broke at one point, then we would have our quick acting flood that could create the channels.

Note: the scientists still do not know of any natural processes that could melt ice that quickly. However, because of this discovery of a possible dam, we have an explanation about why they changed their mind about the flood theory. This new fact offers a reason that helps explain why the scientists changed their mind about the flood theory.

(E)

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SafSin28 · Answer

Question stem: Solve The paradox.

Argument: 
Prehistoric glaciers joined the river by many channels.

The channels were cut by running water.

First theory: the cutting occurred gradually, as the glacier melted.

Second theory: the channels were cut in a short time by an enormous flood.

The channels do show physical evidence of having been formed quickly, but the flood theory was originally rejected because scientists knew of no natural process that could melt so much ice so quickly.

Paradox: today the scientific community accepts the second theory

(A) Rippies, which indicate that the channels were cut by water, have been discovered in the floors of the channels.---> We already knew channels were cut by water. So What? OUT.

(B) The Guiches is known to be similar in certain respects to many other volcanic rock formations. ---> The Guiches = other volcanic rock? So what? OUT.

(C) More than one glacier was present in the area during prehistoric times.---> Come on, who cares of the number of the glaciers? OUT.

(D) Volcanic rock is more easily cut by water than are other forms of rock.--> volcanic rock > other rock in cut with water. So what? OUT.

(E) Scientists now believe that the prehistoric glacier dammed a source of water, created a huge lake in the process, and then retreated. ---> This is a evidence for Flood theory. So E is correct.

The Gulches is an area of volcanic rock that is gashed by many channel

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The Gulches is an area of volcanic rock that is gashed by many channel

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