Find all School-related info fast with the new School-Specific MBA Forum

It is currently 17 Sep 2014, 05:54

Close

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

Prior to 1965 geologists assumed that the two giant

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
2 KUDOS received
Manager
Manager
User avatar
Status: Work hard in silence, let success make the noise
Joined: 25 Nov 2013
Posts: 160
Location: India
Concentration: Finance, General Management
GMAT 1: 540 Q50 V15
GMAT 2: 640 Q50 V27
GPA: 3.11
WE: Consulting (Computer Software)
Followers: 5

Kudos [?]: 29 [2] , given: 84

Prior to 1965 geologists assumed that the two giant [#permalink] New post 10 Dec 2013, 02:32
2
This post received
KUDOS
1
This post was
BOOKMARKED
Prior to 1965 geologists assumed that the two giant rock plates meeting at the San Andreas Fault generate heat through friction as they grind past each other, but in 1965 Henyey found that temperatures in drill holes near the fault were not as elevated as had been expected. Some geologists wondered whether the absence of friction-generated heat could be explained by the kinds of rock composing the fault. Geologists’ pre-1965 assumptions concerning heat generated in the fault were based on calculations about common varieties of rocks, such as limestone and granite; but “weaker” materials, such as clays, had already been identified in samples retrieved from the fault zone. Under normal conditions, rocks composed of clay produce far less friction than do other rock types.

In 1992 Byerlee tested whether these materials would produce friction 10 to 15 kilometers below the Earth’s surface. Byerlee found that when clay samples were subjected to the thousands of atmospheres of pressure they would encounter deep inside the Earth, they produced as much friction as was produced by other rock types. The harder rocks push against each other, the hotter they become; in other words, pressure itself, not only the rocks’ properties, affects frictional heating. Geologists therefore wondered whether the friction between the plates was being reduced by pockets of pressurized water within the fault that push the plates away from each other.

The passage suggests which of the following regarding Henyey’s findings about temperature in the San Andreas Fault?

A.Scientists have yet to formulate a definitive explanation for Henyey’s findings.
B.Recent research suggests that Henyey’s explanation for the findings should be modified.
C.Henyey’s findings had to be recalculated in light of Byerlee’s 1992 experiment.
D.Henyey’s findings provided support for an assumption long held by geologists.
E.Scientists have been unable to duplicate Henyey’s findings using more recent experimental methods.

Source - GMAT Prep
OA -
[Reveal] Spoiler:
A


Can anybody help me explain this question with proper reasoning?
_________________

Sahil Chaudhary
If you find this post helpful, please take a moment to click on the "+1 KUDOS" icon.
My IELTS 7.5 Experience
From 540 to 640...Done with GMAT!!!
http://www.sahilchaudhary007.blogspot.com

Kaplan Promo CodeKnewton GMAT Discount CodesManhattan GMAT Discount Codes
Expert Post
2 KUDOS received
Moderator
Moderator
User avatar
Joined: 01 Sep 2010
Posts: 2401
Followers: 288

Kudos [?]: 2414 [2] , given: 693

Re: Prior to 1965 geologists assumed that the two giant [#permalink] New post 10 Dec 2013, 10:04
2
This post received
KUDOS
Expert's post
sahilchaudhary wrote:
Prior to 1965 geologists assumed that the two giant rock plates meeting at the San Andreas Fault generate heat through friction as they grind past each other, but in 1965 Henyey found that temperatures in drill holes near the fault were not as elevated as had been expected. Some geologists wondered whether the absence of friction-generated heat could be explained by the kinds of rock composing the fault. Geologists’ pre-1965 assumptions concerning heat generated in the fault were based on calculations about common varieties of rocks, such as limestone and granite; but “weaker” materials, such as clays, had already been identified in samples retrieved from the fault zone. Under normal conditions, rocks composed of clay produce far less friction than do other rock types.

In 1992 Byerlee tested whether these materials would produce friction 10 to 15 kilometers below the Earth’s surface. Byerlee found that when clay samples were subjected to the thousands of atmospheres of pressure they would encounter deep inside the Earth, they produced as much friction as was produced by other rock types. The harder rocks push against each other, the hotter they become; in other words, pressure itself, not only the rocks’ properties, affects frictional heating. Geologists therefore wondered whether the friction between the plates was being reduced by pockets of pressurized water within the fault that push the plates away from each other.

The passage suggests which of the following regarding Henyey’s findings about temperature in the San Andreas Fault?

A.Scientists have yet to formulate a definitive explanation for Henyey’s findings.
B.Recent research suggests that Henyey’s explanation for the findings should be modified.
C.Henyey’s findings had to be recalculated in light of Byerlee’s 1992 experiment.
D.Henyey’s findings provided support for an assumption long held by geologists.
E.Scientists have been unable to duplicate Henyey’s findings using more recent experimental methods.

Source - GMAT Prep
OA -
[Reveal] Spoiler:
A


Can anybody help me explain this question with proper reasoning?


Dissect the argument and boile it down to a simple scheme

Now the first sentence says: basically the scientists think that the heat among the earth's plates is caused by the friction of the rocks.

BUT in 1965 Henyey found that temperatures in drill holes near the fault were not as elevated as had been expected.. So after this something is weird: could not be this the real reason behind the friction and the consequent heat. Maybe is the type or quality of the rocks or clay or whatever else.

Byerlee's experiment instead says just this: no matter what is the type of rock, they genarate heat.

BUT pressure itself, not only the rocks’ properties, affects frictional heating. Geologists therefore wondered whether the friction between the plates was being reduced by pockets of pressurized water within the fault that push the plates away from each other.

Basically this is the skeleton of the argument that you have to keep in mind to answer the question. (indeed quite tricky) just because pressure + rock's properties could be the cause of all this but we are still wondering why Is this or there is something else that we do not know ??'

A fits the bill

hope this helps
_________________

COLLECTION OF QUESTIONS
Quant: 1. Bunuel Signature Collection - The Next Generation 2. Bunuel Signature Collection ALL-IN-ONE WITH SOLUTIONS 3. Veritas Prep Blog PDF Version
Verbal:1. Best EXTERNAL resources to tackle the GMAT Verbal Section 2. e-GMAT's ALL CR topics-Consolidated 3. New Critical Reasoning question bank by carcass 4. Meaning/Clarity SC Question Bank by Carcass_Souvik 5. e-GMAT's ALL SC topics-Consolidated-2nd Edition 6. The best reading to improve Reading Comprehension 7.Verbal question bank and Directories

Manager
Manager
User avatar
Joined: 10 Mar 2013
Posts: 200
Followers: 0

Kudos [?]: 8 [0], given: 1737

CAT Tests
Re: Prior to 1965 geologists assumed that the two giant [#permalink] New post 15 May 2014, 18:43
A is supported by the passage via last sentence.
B is not supported by the passage.
C is not supported by the passage.
D (did not have enough time to look at this one.)
E is not supported by the passage.
Re: Prior to 1965 geologists assumed that the two giant   [#permalink] 15 May 2014, 18:43
    Similar topics Author Replies Last post
Similar
Topics:
Prior to 1965 geologists assumed that skrishnakarthik 0 02 Oct 2013, 10:08
Prior to 1965 geologists assumed that the two giant rock raghavs 2 30 Mar 2010, 09:08
Geologists sasen 1 20 Oct 2009, 07:43
2 Prior to 1965 geologists assumed that the two giant rock Gauss 7 19 Jul 2006, 02:08
geologists Janice 3 30 Dec 2004, 17:17
Display posts from previous: Sort by

Prior to 1965 geologists assumed that the two giant

  Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Privacy Policy| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group and phpBB SEO

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.