If early twentieth-century geologists and geo- physicists had heeded

Sajjad1994 thanks for sharing this passage. It was a good read

The Passage

P1: The author introduces the topic - a debate between geologists and geo-physicist

P2: Viewpoint of geologists - Continets must have moved in the past

P3: Viewpoint of geophysicists - The Earth is too strong for continents to have been moved

P4: Viewpoint of the author - Both sides did not consider a concept they knew: "creep". Had they thought about this concept, this futile debate wouldn't have happened

P5: Continuation of author's viewpoint. Some details of creep and Earth's crust.

So what's the passage about? In my opinion, the author is discussing a debate (the viewpoints of two schools of thought) that he believes would not have occurred had a particular concept been considered in the first place.

Questions:

1. The author of the passage is primarily concerned with

(A) presenting new evidence - NO
(B) correcting an oversimplification - NO
(C) analyzing the reasons for a dispute - HOLD
(D) reinterpreting a theory - NO
(E) resolving a dispute between past and present views - NO

Choice (C) is close enough to what we thought. Indeed the author has mentioned the details of two schools of thought and by analyzing the reasons for a dispute he goes ahead and presents his own views in P4 and P5

Answer: (C)

2. It can be inferred from the passage that all of the following are true of the phenomenon of creep EXCEPT:

(A) The effects of creep on normal crystalline solids are always imperceptible. - I don't know what "imperceptible" means so I will hold onto this choice and move to the rest.

(B) The rate of creep is increased by raising the temperature of a solid - Given "Rocks at the Earth's surface are between 600' and 1,000' C below their melting temperatures and thus creep so slowly" and "Within the Earth, however, temperature increases relatively rapidly with depth and, below a few hundred kilometers, creep occurs so readily...

(C) Creep occurs even in relatively large geological structures. - Given. If you read P4 and P5 you will see that the author agrees that the continents move. Why? Because of "creep". Now continents definitely fit under "large geological structures"

(D) Creep operates most rapidly on rocks near their melting point. - Given "The process operates most rapidly in materials near their melting point"

(E) Creep occurs both on and below the Earth's surface. Given "Rocks at the Earth's surface are between 600' and 1,000' C below their melting temperatures and thus creep so slowly that even on geological time scales of millions of years, they may be regarded as brittle and strong solids. Within the Earth, however, temperature increases"

So through POE, we can arrive at (A). But let's analyze (A) to be sure. Now as I mentioned I have no idea what "imperceptible" means BUT it seems to be some negative word. So I guess (A) says that "creep" does not affect normal crystalline solids. Let's go back and re-read the last two sentences of P5 that talks about "crystalline solids"


The bold part shows that even normal crystalline solids are affected by creep and hence act like fluids. Hence (A) is definitely untrue.

Answer: (A)

PS. Sometimes I have no idea about the meaning of the given word. In such a situation the best bet is to (i) Try and apply POE + (ii) guess the meaning to reconfirm your POE.

3. The passage suggests that the author considers the disagreement between early twentieth-century geologists and geophysicists to have been

(A) confusing - NO
(B) inevitable - NO
(C) surprising and inexplicable - NO
(D) hostile but ultimately useful - Hold
(E) needless and unproductive - Hold


Reading the above in P1 I feel (E) fits BUT the words "sterile" and "bitter controversy" make me think if (D) the word "hostile" fits? However, I am not sure of " ultimately useful" So I am a bit skeptical of (D)


Reading the above bold face reconfirms that (E) is the answer.

Answer: (E)

4. According to the passage, the theoretical position of early twentieth-century geologists was based on which of the following?

P2 talks about "geologists" and their theoretical position. So we can re-read P2 and see that:

I. The shapes of the Earth's continents - P2 - so yes
II. The evidence of ductility in rocks - P4 - so no
III. The fossil record - P2 - so yes

Answer: (D)

5. It can be inferred from the passage that which of the following statements best expresses the "strength paradox" (Highlighted)?

To answer this question, it would be best to go back and re-read P4 and get a solid grip on "Strength paradox"

- The "strength paradox" had been familiar to generations of geologists from the study of rock deformations in mountain belts
- From this study, they observed that some quite rigid rocks had in the past been highly ductile, on occasion even vicious. (I have no idea what the meaning of these words are but they appear to be something negative)
- Geologists and geophysicists knew about the concept of "creep" BUT did not consider this concept.
- High stress --> faster decomposition --> Creep rate is high. Low stress --> slower decomposition --> creep rate is low

No mention of chemical composition.

Why would rocks high up on the mountains - thus subjected to low stress - be more fluid? In fact, rocks below the Earth's surface have high pressure and hence will be in a fluid state. (Read last two sentences of P5)

As we saw, stress determines the state of the rock. Moreover, think about "strength paradox". We all know the term "paradox" thanks to CR :') So what would be so paradoxical of "strengthen of rocks" ---> Well rocks are strong BUT this strength depends on the pressure to which they are subjected. High pressure --> rocks in a fluid state. Lower pressure --> Strong and solid-state.

I can't find "scene locations" anywhere in the argument.


I would like some expert to comment on (E). All I can say is that "creep" has been mentioned later in the passage. There is no connection shown between "mountain belts" and "creep"

Answer: (C)

6. According to the author of the passage, geologists and geophysicists could have resolved their theoretical argument if they had

By now we know that "creep" was a concept that the two didn't consider despite of the geologists knowing "that some quite rigid rocks had in the past been highly ductile, on occasion even vicious". So the correct answer choice will highlight this idea. (Read P4)

(A) more carefully reviewed the fossa evidence - NO - This is evidence used by geologists to make their case (read P2)
(B) closely examined the physical appearance of the Earth's surface rock - NO - No physical appearance has been mentioned as evidence to be used to prove any point of view.
(C) applied their knowledge of the effects of stress to the geological evidence - YES - in line with what we thought
(D) known about the phenomenon of creep - NO - "failed to connect this evidence with a phenomenon they knew" (read P4)
(E) understood more completely the effects of phenomena such as earthquakes - NO - Used as evidence by geophysicists to make their point (read P3)

Answer: (C)

7. The author suggests that the major reason for the disagreement between early twentieth-century geologists and geophysicists was that each group

(A) reached conflicting conclusions from separate analyses of the fossil record - NO - only geologists used fossil records (read P1)
(B) interpreted the evidence of rock deformations differently - NO - nowhere has this been mentioned in the passage
(C) examined data on different kinds of phenomena - HOLD - the author states in P1 that the argument could have been avoided had the two groups agreed to the idea "Everything flows". So had the two groups fixed on one common thought the debate wouldn't have taken place. Later in P2 and P3 the author goes ahead and describes the viewpoints and the evidence backing the two viewpoints of these two groups. Thus the author shows why these two schools of thought arrived at two different conclusions leading to a debate that could have been avoided in the first place.
(D) based their respective theories on conflicting estimates of the Earth's age - NO - Nowhere has this been mentioned
(E) made different though equally inaccurate assumptions about the Earth's history - NO - no assumptions about the Earth's age has been used as evidence

Answer: (C)

8. Which of the following best describes the organization of the passage?

Making a short summary of each paragraph will help us get an idea of the passage and thus answer "Primary purpose" and "organization of the passage" type questions.


The passage presents two viewpoints about a phenomenon and not one. Moreover, the argument is about an overall debate and the reasons for the debate. This choice fails to cover that aspect


A debate is presented and its irrelevance is highlighted by covering a concept that the two groups forgot to consider.


I am okay with "a scientific dispute" BUT what are the possible resolutions? The author doesn't list down various resolutions. He simply states the reasons and irrelevance of the dispute


Pretty much every word of this sentence is incorrect. The author doesn't present A hypothesis/ He rather presents two viewpoints on one scientific topic. Moreover, the author doesn't bring in "new" evidence. He rather talks about a concept that the two groups knew but failed to consider while evaluating their arguments. Lastly, the author does not support the validity of an idea. He rather is trying to tell us how unproductive and irrelevant this entire debate was.


Well, given that we rejected all four choices, this has to be the answer, or else we will need to go back and start being more "open" to a few choices. However, this choice does cover the passage by and large. Yes, the irrelevance of a debate is not covered BUT it does talk about (i) scientific dispute, which is the same as a debate. (ii) summary of this debate: In P1 the author introduces the topic and gives us his view already about how this debate would not have taken place had they agreed to the Greek philosopher Heraclitus. (iii) reasons for the occurrence of this debate are offered: P2 and P3 talk about the evidence used by each group to back their viewpoint. P4 talks about why these two groups arrive at two different conclusions - They forgot about the concept "creep". P5 further elaborates on this concept.

Answer: (E)

9. Which of the following statements, if true, is most compatible with the principle underlying the geophysicists' citation of Mt. Everest as evidence for their theories?

This idea is covered in P3. So we should go back and re-read the para. Clearly, the idea conveyed is that the mountain is as string as the base. If the base is weak, the structure will collapse.

(A) A one-hundred-story building must have a much stronger base than is necessary for a twenty-story building of similar materials. - YES- This is exactly what we mentioned above. The taller the structure the stronger the base or else it would collapse.
(B) A thin external material like glass makes a skyscraper less vulnerable to stress from wind than does a thick material like brick. - NO - the material is not something that has been discussed.
(C) The girders supporting the ceilings and floors on higher levels of a multistory building must be stronger than those supporting ceilings and floors on lower levels. - NO - We know that the base must be stronger. So the grinders at the base must be stronger than the grinders on higher floors.
(D) Multistory buildings in earthquake zones must obey height restrictions because of the probability of seismic stress. - NO - height restrictions are not covered in the passage. All we care about is taller the structure = stronger the base.
(E) Buildings with foundations composed of relatively rigid materials art less subject to creep. - NO - Material is not discussed. Besides "creep" depends on the temperature of the rocks and not the rigidity of the material.

Answer: (A)

KarishmaB GMATNinja if you have the time please could you share your views on Q5. option (E). I am not exactly sure why this choice is incorrect. I didn't find the official explanation quite convincing