扫描二维码，直接登录
题库 / Prep2008E1-RC-1
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 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. 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. 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. 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.
The passage suggests that if the scientists mentioned in the highlighted text 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
此讲解的内容由AI生成，还未经人工审阅，仅供参考。
正确答案是 E。因为文中提到，当月球早期受到大型撞击物的冲击，会导致数百万立方公里的地壳碎片被喷射出来，而这些碎片会被密度更高的来自月球地幔的物质立即补上，因此导致最终形成的盆地不会有低引力异常。然而，当月球变得冷而且比较僵硬时，撞击物的反弹力不完整，也就是说，今天发生撞击时，不太可能发生这种引力补偿，因为月球外层太冷而且太僵硬了。所以，答案是 E，这些大型多圈撞击盆地在月球相对比较有弹性时形成。
绕晕了，科学家假设的是早期的月亮并没有重力异常，题目问发生重力异常的时候，所以肯定是选A了
第二次错
选反了，，，，，，，，哎
问的是没有重力补偿时时候，就是有坑的时候，但是早期的月亮是elastic 不冷的所以是不会产生坑的
significant negative gravity anomalies 》无compensation
定位关键句：Thus today such gravitational compensation probably would not occur: 也就是这个compensation只在early时期发生
挺绕的
请问一下这道题的答案到底是A还是E呀？AI考题讲解里面说是E。。。
你肯定把题目看反了
点错了
有重力补偿，就没有negative gravity anomalies,
题目说的有最明显的negative gravity anomalies的话，说明就没有重力补偿，所以要找到没有重力补偿是什么情况-->现在没有重力补偿了，但是在early in lunar history是有的
significant negative gravity anomalies 》无compensation
定位关键句：Thus today such gravitational compensation probably would not occur: 也就是这个compensation只在early时期发生
问最可能有negative gravity的情况，文中说前面Moon比较elastic，物质可以从mantle补充上来，后来cold and cliff了，就不行了，肯定选A。搞晕了选了E
没有和前一句联系起来看。
阅读第一题读太快选太快
the most significant negative gravity anomalies 一定是发生在月亮自身不可以compensate的时候，也就不是月亮的早期（早期文中提到可以compensate）
large body strikes =>low gravity
paradox:many basins have no low gravity.
scientists speculate:[early]moon elastic=> gravity compensation(no low gravity)
[later]moon stiff and cooler=> gravity compensation may not occur (low gravity)
还是因为文章绕过来绕过去 没读懂意思的原因！文章说的是 早期因为有弹性 leaving no low gravity anomaly in the resulting basin.
如果科学家所说的是真的→那么早期不会形成重力异常，只有后期月球弹性小、寒冷的情况下才会造成
hus leaving no low gravity anomaly in the resulting basin.
题目看错了..
thus leaving 【no】 low gravity anomaly in the resulting basin
anomaly n. 异常；不规则；反常事物
这题居然感觉5个选项都对服了