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 is supported by the information in the passage?

(A) Only running water can cause deep channels in volcanic rock.

(B) The river did not exist before the channels were cut.

(C) Geologists cannot determine the amount of heat required to melt a glacier quickly.

(D) The physical effects of water on rock vary with the speed with which those effects are produced.

(E) Geologists are compelled to reject physical evidence when it leads to an unexplainable conclusion.

gmat1393 · Answer

Hi  Bunuel

Please change the tag to Inference, this is not an Assumption Type question

Thanks

Rameshllll · Answer

D and E both are close ....can't see how to reject E.

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analytica233 · Answer

(E) is incorrect because the geologists acknowledge the physical evidence that the channels were formed quickly. What they rejected initially was the flood THEORY to explain the physical evidence.

anshulvnd5 · Answer

Can anyone explain why Option A is incorrect

rohit8865 · Answer

it is quoting a generic view ...

anshulvnd5 · Answer

I am still not getting it, I mean this generic view is right ?

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unraveled · Answer

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 is supported by the information in the passage?

(A)  Only  running water  can cause deep channels  in volcanic rock. - WRONG. Bit extreme claim to make.

(B) The river  did not exist before  the channels were cut. - WRONG. Again like A a bit extreme claim.

(C) Geologists  cannot determine the amount of heat required to melt  a glacier quickly. - WRONG. They may know or they may not.

(D) The physical effects of water on rock  vary with the speed with which those effects are produced . - CORRECT. Aligns with the blue text.

(E) Geologists are  compelled to reject physical evidence  when it leads to an unexplainable conclusion. - WRONG. They din't accept earlier but now they accept that theory.

Answer D.

arthurchichester · Answer

D and E are not close at all,
Considering E, there is no compulsion stated in the para to straight up reject  physical evidence when it leads to an unexplainable conclusion , its too extreme of a choice.
D on the other hand, sums up the underlying fact on which the para is based.

DmitryFarber · Answer

We need an answer that is fully supported by the given info. All the text tells us is that these particular trenches were clearly cut by running water. That doesn't mean that water is the only thing that can EVER cause deep channels. Even if we knew this to be true in real life, that wouldn't make it supported by the text. (A could say that 10 > 2, and it still wouldn't be supported  by the text .)

8Harshitsharma · Answer

E is the opposite of what is stated in the passage. One  geologist   proposed  that channels were cut by a flood, not reject it. The  SCIENTIFIC community rejected  the theory because they didn't have an explanation for that.

We don't know for sure that Geologists rejected anything with the info presented in the passage. Maybe geologists believed in it but other scientists disagreed with the flood theory so they also had to keep shush and agree with the larger community.

akshaypratap278 · Answer

(A) Only running water can cause deep channels in volcanic rock.
- 'Only' is very strong. Can't be sure on this.

(B) The river did not exist before the channels were cut.
- Again very strong. Who know, they exist before too?

(C) Geologists cannot determine the amount of heat required to melt a glacier quickly.
- Nothing about the 'heat'. So can't be sure here too.

(D) The physical effects of water on rock vary with the speed with which those effects are produced.
- True. See in passage when we talk about glacier melting (here the speed of water will be slow), we say 'gradually'. But with enormous floods (when speed will be high), it is cut quickly. CORRECT.

(E) Geologists are compelled to reject physical evidence when it leads to an unexplainable conclusion.
- They didn't reject. They were the one who proposed and there were physical evidence to it too.

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

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