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 1831 when Smith was finally recognized by the Geological Society of London as the "father of English geology," it was not onl
In 1831 when Smith was finally recognized by the Geological Society of London as the "father of English geology," it was not onl
admin
2014-09-29
57
问题
In 1831 when Smith was finally recognized by the Geological Society of London as the "father of English geology," it was not only for his maps but also for something even more important. Ever since people had begun to catalog the strata in particular outcrops, there had been the hope that these could somehow be used to calculate geological time.
But as more and more accumulations of strata were cataloged in more and more places, it became clear that the sequences of rocks sometimes differed from region to region and that no rock type was ever going to become a reliable time marker throughout the world.
Even without the problem of regional differences, rocks present a difficulty as unique time markers.
Quartz is quartz
—a silicon ion surrounded by four oxygen ions—there’s no difference at all between two-million-year-old Pleistocene quartz and Cambrian quartz created over 500 million years ago.
Why does the author use the phrase "
Quartz is quartz
"?
选项
A、To describe how the differences between Pleistocene and Cambrian quartz reveal information about dating rocks
B、To point out that the chemical composition of quartz makes it more difficult to date than other rocks
C、To provide an example of how regional differences in rock sequences can make a particular rock difficult to date
D、To explain that rocks are difficult to use for dating because their chemical compositions always remain the same over time
答案
D
解析
转载请注明原文地址:https://kaotiyun.com/show/gHfO777K
0
托福(TOEFL)
相关试题推荐
Completethetablebelow.WriteNOMORETHANTHREEWORDSforeachanswer.Parksandopenspaces
Completetheformbelow.WriteONEWORDAND/ORANUMBERforeachanswer.
Completetheformbelow.WriteONEWORDAND/ORANUMBERforeachanswer.
Labeltheplanbelow.WriteNOMORETHANTHREEWORDSforeachanswer.PlanoftheBritishLibrary
Choosethecorrectletter,A,BorC.Kathyasksthetutorforhelpwiththe______section.
Completethenotesbelow.WriteNOMORETHANTHREEWORDSforeachanswer.GIVINGASPEECHReasonsfornervousnessLecturersofte
Choosethecorrectletter,A,BorC.Thestudenthastheabilityof
Completethenotesbelow.WriteONEWORDONLYforeachanswer.Episodicmemory-theabilitytorecalldetails,e.g.thetimeand
Completethenotesbelow.WriteONEWORDONLYforeachanswer.Episodicmemory-theabilitytorecalldetails,e.g.thetimeand
Listenandcompletetheinformationbelow.Howmuchdoesthemanneedtopayforthebustickets?$______
随机试题
铅垂线在其投影面上聚积为()。
男性,42岁,饮酒史15年,平均每天50度白酒5两,查体发现ALT78IU/L、AST120IU/L、ALP254IU/L、GGT324IU/L,B超提示:肝脏弥漫性损害伴肿大、重度脂肪肝,肝炎病毒标志物阴性。各种病毒性肝炎中,易产生肝细胞脂肪变性的是
根据水利工程概算编制有关规定,施工企业利润应按直接工程费和间接费之和的()%计算。
在摩托车的喷漆工序中,为了控制喷漆中的疵点,应采用()。
青海因境内有国内最大的内陆咸水湖()而得名,简称“青”。
中国古代佛教兴盛,出现了很多著名的佛像石窟,其中被称为中国古代彩塑博物馆的石窟是()。
行使管制权的主体是乡级以上人民政府的公安机关。( )
如果太看重结果,失败就会给人们带来许多烦恼。但是如果我们把注意力放在过程上,从中发现解决问题的快乐,那么即使最后失败了,影响也会小很多。而且,我们可以从失败中总结出有用的经验,有了这些积累,成功自然离我们越来越近。根据这段话,怎样才能让失败的影响变小?
IftherewasonethingAmericanshadarighttoexpectfromCongress,itwasafederalplantohelptheelderlypayforprescrip
Ininternationalmatches,prestigeissoimportantthattheonlythingthatmattersistoavoid
最新回复
(
0
)