gwd17-35-37

Q35 to Q37:

(This passage was excerpted from material

published in 1996.)

                 When a large body strikes a planet

          or moon, material is ejected, thereby

          creating a hole in the planet and a local

Line      deficit of mass.  This deficit shows up

(5)      as a gravity anomaly:  the removal of

the material that has been ejected to

make the hole results in an area of

slightly lower gravity than surrounding

areas.  One would therefore expect that

(10)     all of the large multi-ring impact basins

on the surface of Earth’s Moon would

show such negative gravity anomalies,

since they are, essentially, large holes

in the lunar surface.  Yet data collected

(15)      in 1994 by the Clementine spacecraft

show that many of these lunar basins

have no anomalously low gravity and

some even have anomalously high

gravity.  Scientists speculate that early

(20)      in lunar history, when large impactors

         struck the Moon’s surface, causing

         millions of cubic kilometers of crustal

debris to be ejected, denser material

from the Moon’s mantle rose up

(25)      beneath the impactors almost imme-

diately, compensating for the ejected

material and thus leaving no low gravity

anomaly in the resulting basin.  Later,

however, as the Moon grew cooler

(30)      and less elastic, rebound from large

impactors would have been only partial

and incomplete.  Thus today such

       gravitational compensation probably

would not occur:  the outer layer of

the Moon is too cold and stiff.

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Q35:

According to the passage, the gravitational compensation referred to in line 33 is caused by which of the following?

A deficit of mass resulting from the creation of a hole in the lunar surface

The presence of material from the impactor in the debris created by its impact

The gradual cooling and stiffening of the Moon’s outer layer

The ejection of massive amounts of debris from the Moon’s crust

The rapid upwelling of material from the lunar mantle

Answer: e

mine :d--------------------------------------------------------------------------------

定位在19-28行那一句话.   D是说重力场是怎样产生的. 而题目问的是重力场是怎样被补偿的.

Q36:

The passage suggests that if the scientists mentioned in line 19 are correct in their speculations, the large multi-ring impact basins on the Moon with the most significant negative gravity anomalies probably

were not formed early in the Moon’s history

were not formed by the massive ejection of crustal debris

are closely surrounded by other impact basins with anomalously low gravity

were created by the impact of multiple large impactors

were formed when the Moon was relatively elastic

Answer: a

mine e

定位在19-28行那一句话,还有末段最后一句话----在早期,大的basin不会产生是因为它们被19-28说的补偿拉.  E正好把这事说反拉.

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Q37:

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

An anomalous finding is cited, the data used to support that finding are analyzed, and the finding is modified.

A theory about a phenomenon is introduced, data seeming to disprove that theory are analyzed, and the theory is rejected.

A phenomenon is described, a finding relating to the phenomenon is discussed, and a possible explanation for that finding is offered.

A debate among scientists regarding the explanation for a particular phenomenon is outlined, and one position in that debate is shown to be more persuasive.

The observation of an astronomical event is described, and two schools of thought about the explanation for that event are discussed.

Answer: c

mine:b

B不对是因为没有什么理论提出并被disprove.  C中说的possible explanation就是原文

19-28行说的那事.

debris to be ejected, 这种补偿就发生了，所以D才是cause。

这是我的理解。

      When a large body strikes a planet or moon, material is ejected, thereby creating a hole in the planet and a local

Line       deficit of mass.  This deficit shows up as a gravity anomaly:  the removal of the material that has been ejected to

make the hole results in an area of slightly lower gravity than surrounding areas.

大天体撞击星球或者月亮，物质就会被喷射出来，从而产生一个大洞和质量不足。质量不足反映为重力场的不规则：导致大洞的重力低于周围的地区

One would therefore expect that all of the large multi-ring impact basins on the surface of Earth’s Moon would

show such negative gravity anomalies, since they are, essentially, large holes in the lunar surface.  

因此，人们推测月亮上的环形山show负的重力不规则，即重力比周围小

Yet data collected in 1994 by the Clementine spacecraft show that many of these lunar basins have no anomalously low gravity and some even have anomalously high gravity.  Scientists speculate that early in lunar history, when large impactors struck the Moon’s surface, causing millions of cubic kilometers of crustal debris to be ejected, denser material from the Moon’s mantle rose up beneath the impactors almost immediately, compensating for the ejected

material and thus leaving no low gravity anomaly in the resulting basin.

但是，数据显示月球上的盆地没有负重力不规则，部分地区还有high gravity高重力。科学家猜测，在月球早期，当大星体撞击月球表面，导致地壳碎片被喷射出去，物质从月球地幔层上升并denser，compensating补偿了喷射出去的物质，从而没有造成负重力不规则。

Later, however, as the Moon grew cooler and less elastic, rebound from large impactors would have been only partial and incomplete.  Thus today such gravitational compensation probably would not occur:  the outer layer of

the Moon is too cold and stiff.

然而，后来，月球变冷，不再有弹性...因此，今天 重力的补偿不可能再出现了。

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Q35:

According to the passage, the gravitational compensation referred to in line 33 is caused by which of the following?

1. A deficit of mass resulting from the creation of a hole in the lunar surface


2. The presence of material from the impactor in the debris created by its impact


3. The gradual cooling and stiffening of the Moon’s outer layer


4. The ejection of massive amounts of debris from the Moon’s crust


5. The rapid upwelling of material from the lunar mantle

答案E  upwelling对应rose up。有些人说D正确，注意ETS习惯用分词compensating表示因果关系，对应题目中的caused by（很多语法和阅读题都是这个考点）。排除D，是因为重力补偿是因为地幔的上升才会有补偿，而如果地幔不上升，仅仅是有星球撞击月球并喷射出碎片，是不一定能造成重力补偿的。

when large impactors struck the Moon’s surface, causing millions of cubic kilometers of crustal debris to be ejected, denser material from the Moon’s mantle rose up beneath the impactors almost immediately, compensating for the ejected

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Q36:

The passage suggests that if the scientists mentioned in line 19 are correct in their speculations, the large multi-ring impact basins on the Moon with the most significant negative gravity anomalies probably

1. were not formed early in the Moon’s history


2. were not formed by the massive ejection of crustal debris


3. are closely surrounded by other impact basins with anomalously low gravity


4. were created by the impact of multiple large impactors


5. were formed when the Moon was relatively elastic

答案A。 注意20行early in lunar history和32行的today，文末说如果今天，月球变冷不再有弹性，就不会产生重力补偿（是负重力不规则的取反），因此肯定不会发生在早期。

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Q37:

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

1. An anomalous finding is cited, the data used to support that finding are analyzed, and the finding is modified.


2. A theory about a phenomenon is introduced, data seeming to disprove that theory are analyzed, and the theory is rejected.


3. A phenomenon is described, a finding relating to the phenomenon is discussed, and a possible explanation for that finding is offered.


4. A debate among scientists regarding the explanation for a particular phenomenon is outlined, and one position in that debate is shown to be more persuasive.


5. The observation of an astronomical event is described, and two schools of thought about the explanation for that event are discussed.

答案C 。 先描述一个现象（负重力不规则），一个finding关于月球表明的正重力不规则，一个可能的解释（地幔上升的重力补偿）

thank you very much!追逐梦想2006

It's really a nice job! Thank you very much!追逐梦想2006.

好帖 赞一个

谢谢追逐梦想 2006

谢谢追逐梦想 2006...very helpful!

36题绕了几圈把我绕晕了。呵呵，原来是with the most significant negative gravity，而文章讨论的moon反常的地方恰恰是在早期出现，如果出现典型负重力场那么就应该是不冷没弹性的，咳，晕了

追逐梦想2006

寫的真棒!!!拍拍手~~

很感謝!