首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
In Death Valley, California, one of the hottest, most arid places in North America, there is much salt, and salt can damage rock
In Death Valley, California, one of the hottest, most arid places in North America, there is much salt, and salt can damage rock
admin
2014-01-13
43
问题
In Death Valley, California, one of the hottest, most arid places in North America, there is much salt, and salt can damage rocks impressively. Inhabitants of areas elsewhere, where streets and highways are salted to control ice, are familiar with the resulting rust and deterioration on cars. That attests to the chemically corrosive nature of salt, but it is not the way salt destroys rocks. Salt breaks rocks apart principally by a process called crystal prying and wedging. This happens not by soaking the rocks in salt water, but by moistening their bottoms with salt water. Such conditions exist in many areas along the eastern edge of central Death Valley. There, salty water rises from the groundwater table by capillary action through tiny spaces in sediment until it reaches the surface.
Most stones have capillary passages that suck salt water from the wet ground. Death Valley provides an ultra-dry atmosphere and high daily temperatures, which promote evaporation and the formation of salt crystals along the cracks or other opening within stones. These crystals grow as long as salt water is available. Like tree roots breaking up a sidewalk, the growing crystals exert pressure on the rock and eventually pry the rock apart along planes of weakness, such as banding in metamorphic rocks, bedding in sedimentary rocks, or preexisting or incipient fractions, and along boundaries between individual mineral crystals or grains. Besides crystal growth, the expansion of halite crystals(the same as everyday table salt)by heating and of sulfates and similar salts by hydration can contribute additional stresses. A rock durable enough to have withstood natural conditions for a very long time in other areas could probably be shattered into small pieces by salt weathering within a few generations.
The dominant salt in Death Valley is halite, or sodium chloride, but other salts, mostly carbonates and sulfates, also cause prying and wedging, as does ordinary ice. Weathering by a variety of salts, though often subtle, is a worldwide phenomenon. Not restricted to arid regions, intense salt weathering occurs mostly in salt-rich places like the seashore, near the large saline lakes in the Dry Valleys of Antarctica, and in desert sections of Australia, New Zealand, and central Asia.
The word "shattered" in line 20 is closest in meaning to______.
选项
A、arranged
B、dissolved
C、broken apart
D、gathered together
答案
C
解析
根据文章第二段最后一句“A rock durable enough to have withstood naturalconditions for a very long time in other areas could probably be shattered into small pieces by saltweathering within a few generations.”可知,在其他自然环境下,即使岩石具有持久的耐力,但是经过几代之后,也很有可能被盐风化成小碎片。从后面的small pieces,可知是broken apart。据此判断,答案是C。
转载请注明原文地址:https://jikaoti.com/ti/ur6YFFFM
0
考博英语
相关试题推荐
Intheirworldofdarkness,itwouldseemlikelythatsomeoftheanimalsmighthavebecomeblind,ashashappenedtosomecave
Theworseningfinancialsituationmadeitobviousthataneconomicdepressionwas______.
Bacteria(细菌),likepeople,canbedividedintofriendandfoe.61.Inspiredbyevidencethatthefriendlysortmayhelpwitha
Bacteria(细菌),likepeople,canbedividedintofriendandfoe.61.Inspiredbyevidencethatthefriendlysortmayhelpwitha
AnOhioStateUniversitystudyhaslinkedbehaviorinyoungchildren【C1】______thetypeofjobtheirmotherhas.Motherswithcom
Withhumanfootprintsonthemoon,radiotelescopeslisteningformessagesfromaliencreatureswhomayormaynotexist,techni
Inspiteof"endlesstalkofdifference",Americansocietyisanamazingmachineforhomogenizingpeople.Thereis"thedemocrati
Thebusinessofadvertisingistoinventmethodsofaddressingmassiveaudiencesinalanguagedesignedtobeeasilyaccessible
TheInternationalCommitteeoftheRedCrosssaysitwillneednearly$650milliontohelpvictimsofarmedconflictandviolen
ThecrucialyearsoftheDepression,astheyarebroughtintohistoricalfocus,increasinglyemergeasthedecisivedecadeforA
随机试题
生产周期
阅读下面的古诗,回答问题。别离陆龟蒙丈夫非无泪,不洒离别间。杖剑对尊酒,耻为游子颜。蝮蛇一螫手①,壮士即解腕②。所志在功
3岁女孩,主因眼睑及面部水肿两周就诊。查体:血压90/68mmHg,全身高度水肿,呈凹陷性。实验室检查尿蛋白++++,尿红细胞1~2/HP。确诊最有价值的辅助检查是
关于债券的估值方法,下列说法错误的是()。
封闭式基金存续期满后必须终止。( )
下列哪一种中药材不准出境()
社会政策制定涉及多方面的要素和内容,社会政策制定的内容主要包括()。
制定世界上第一部成文宪法的国家是
2001年中共中央印发的《公民道德建设实施纲要》中规定了公民基本道德规范的主要内容。公民道德建设的重点是()
WhyisPhilworried?
最新回复
(
0
)