GRE阅读Passage 30
One reason researchers have long believed that Mars never enjoyed an extensive period of warm and wet climate is that much of the surface not covered by wind-borne dust appear to be composed of unweathered material. If water flowed for an extended period, researchers reasoned, it should have altered and weathered the volcanic minerals, creating clays or other oxidized, hydrated phases (minerals that incorporate water molecules in their crystal structure.) It turns out, though, that the scientists were not looking closely enough. New high- resolution mapping data and close-up surface studies have revealed clays and other hydrated minerals in many regions. The clay deposits are scattered all over, in ancient volcanic surfaces and heavily cratered highland regions, some of which have apparently been exposed by erosion only recently.文章解析
白话版讲解:
研究人员长时间以来一直认为火星从来没有经历过一个较长时期的温暖而湿润的气候。研究人员之所以这样想,其中一个原因是他们发现火星上大部分没被风吹来的灰尘覆盖的表面,好像都是由没经过侵蚀(雨淋日晒水泡)的物质组成的。研究人员是这样推理的:如果水曾经在火星表面流过比较长的一段时间(即河流曾经在火星表面存在过一段时间),那火星表面的火山矿物质应该被河流河水侵蚀过,结构应该发生改变,会形成黏土(clay),或变成其他氢化和氧化物(即火山矿物质本来的晶体结构会将水分子中的氢和氧纳入,形成新的晶体结构,进而形成和clay差不多的新的化合物)。而在火星上没有找到这种经过侵蚀(雨淋日晒水泡)的clay类物质,所以河流并没有在火星表面存在过较长一段时间。 注解: 请注意最后一句话的which指highland regions,不是指the clay deposits。 但是,现在发现,之前研究人员观察得不够仔细。最新获得的高分辨率绘图数据和贴近火星表面的近距离特写研究发现,火星表面很多地区其实是有黏土(clay)和其他含水矿物质的。其实火星表面很多地区都有clay的天然沉积层,在古老的火山口表面,找到了clay;密布陨石坑的高地区域,也找到了clay。而且,其中有些高地区域看起来是最近被(水)腐蚀过泡过(这些高地区域的clay是不久前形成的。)题目解析
1. According to the passage, scientists are able to discover weathered material on the Martian surface because they have benefited from which of the following? A. a new method to analyze volcanic craters created on the Martian surface B. an improved ability to detect hydrated materials on the Martian surface C. a more sophisticated understanding of the effect of wind-borne dust on the Martian surface D. a decision to look for water primarily in heavily cratered highland regions. E. a better understanding of how erosion might affect clay deposits.白话版讲解:
问根据文章,科学家们是得益于什么事,才能够在火星表面发现了经过腐蚀(雨淋水泡)的物质? 根据文章第二自然段第二句话“New high- resolution mapping data and close-up surface studies have revealed clays and other hydrated minerals in many regions.”,可选出正确选项B。 本题答案:B Consider each of the choices separately and select all that apply. 2. It can be inferred from the passage that the author would agree with which of the following statements regarding the reasoning discussed in the highlighted sentence? A. It provides the basis for an explanation of why water on Mars has been difficult to find until recently. B. It correctly identifies a consequence of water flowing on the Martian surface. C. It depends on a false assumption about how water and volcanic materials interact on Mars.白话版讲解:
在突出显示(高亮)的那句话中,进行了一个推理,关于这个推理,下列五个说法,作者会同意哪个? A“该推理为解释一个问题提供了基础,这个问题是,为什么一直都很难在火星上发现水,直到最近才容易发现” 文章不是关于在现在的火星上面去找现在有没有水,而是找是否有火星历史上存在过河流、温暖气候的证据。所以A选项错误。 B“该推理正确地指出了水在火星表明流过会产生的一个后果” 高亮突出显示的那句话中的“altered and weathered the volcanic minerals, creating clays or other oxidized, hydrated phases”就是B选项中的“a consequence of water flowing……”,所以B选项正确。 C“该推理依靠一个错误的关于火星上的水和火山矿物质会这样发生反应的臆断” 从全文看,作者并不反对该推理本身。文章中说it should have altered and weathered the volcanic minerals, creating clays or other oxidized, hydrated phases (minerals that incorporate water molecules in their crystal structure正是C选项中所说的“assumption about how water and volcanic materials interact on Mars”,但是文章作者并不认为这个assumption是false的。所以C选项错误。 注解: 三个选项中it,都是指题干中的the reasoning discussed……。 本题答案:BTD福利 & 领取方式
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