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
Standing on the rim of the Grand Canyon(大峡谷), gazing across this giant would in the Earth’s surface, a visitor might assume that
Standing on the rim of the Grand Canyon(大峡谷), gazing across this giant would in the Earth’s surface, a visitor might assume that
admin
2013-05-13
57
问题
Standing on the rim of the Grand Canyon(大峡谷), gazing across this giant would in the Earth’s surface, a visitor might assume that the canyon had been caused by some ancient convulsing (震动). In fact, the events that produced the canyon, far from being sudden and catastrophic, simply add up to the slow and orderly process of erosion.
Many millions of years ago, the Colorado Plateau in the Grand Canyon area contained 1000 more feet of rock than it does today and was relatively level. The additional material consisted of some 14 layered formations of rock. In the Grand Canyon region these layers were largely worn away over the course of millions of years.
Approximately 65 million years ago the plateau’s flat surface in the Grand Canyon area bulged upward from internal pressure, geologists refer to this bulging actions upwading(弯 曲上升); it was followed by a general elevation of the whole Colorado Plateau, a process that is still going on. As the plateau gradually rose, shallow rivers that winded across it began to run more swiftly and cut more definite courses. One of these rivers, located east of the upward, was the ancestor of the Colorado. Another river system, called the Hualapai, flowing west of the upward, extended itself eastward by cutting back into the upward, it eventually connected with the ancient Colorado and captured its waters. The new river then began to carve out the 277-mile-long trench that eventually became the Grand Canyon. Geologists estimate that this initial cutting action began no earlier than 10 million years ago.
Since then, the Canyon forming has been cumulative. To the corrosive force of the river itself have been added other factors. Heat and cold, rain and snow, along with the varying resistance of the rocks, increase the opportunities for erosions. the Canyon walls crumble, the river acquires a cutting tool. Tons of debris, rainfall running off the high plateau creates feeder streams that carve side canyons. Pushing slowly backward into the plateau, the side canyons expose new rocks, and the pattern of erosion continues.
The passage would most likely be found in a texbook on which of the following subjects?
选项
A、Astronomy.
B、Botany(植物学).
C、Geology.
D、Chemistry.
答案
C
解析
从文章内容上可以看出本篇不是天文学、植物学,也不是化学,而是地质学方面的内容。因而选[C]。
转载请注明原文地址:https://kaotiyun.com/show/GVjd777K
本试题收录于:
公共英语三级笔试题库公共英语(PETS)分类
0
公共英语三级笔试
公共英语(PETS)
相关试题推荐
Whatcanwelearnfromtheconversation?
Text…【C1】______Thanksgivingturkey,it’shardtofind【C2】______"American"food.TheUnitedStatesisalandof【C3】______
Thefollowingfivetalksaredifferentopinionsaboutworkingathomeinsteadofworkinginofricesinthecentreoftowns.
Text…Themessageof【C1】______suchasthisis【C2】______naturalsystemsarecomplex,unpredictable:understandingthem【C3】
Publicimage【C1】______tohowacompanyisviewedbyitscustomers,suppliers,andstock-holders,bythefinancialcommunity,by
Publicimage【C1】______tohowacompanyisviewedbyitscustomers,suppliers,andstock-holders,bythefinancialcommunity,by
Alandfreefromdestruction,pluswealth,naturalresources,andlaborsupply...allthesewereimportant【C1】______inhelpingEn
Alandfreefromdestruction,pluswealth,naturalresources,andlaborsupply...allthesewereimportant【C1】______inhelpingEn
Alandfreefromdestruction,pluswealth,naturalresources,andlaborsupply...allthesewereimportant【C1】______inhelpingEn
随机试题
Agoodmodernnewspaperisanextraordinarypieceofreading.Itisremarkablefirstforwhatitcontains:therangeofnewsfro
男性,38岁,入院诊断为急性胰腺炎,在恢复过程中,饮肉汤一碗,再发上腹部剧痛,注射654—2无效,并出现腹胀。处理应是
人体内再生能力最强的细胞是
周某与林某协议离婚时约定,孩子归女方林某抚养,周某每年给付1000元抚养费。离婚后,因林某将孩子由姓周改姓林,周某就停止给付抚养费。因这一年年景不好,周某就将卖粮仅得的1000元捐献给了希望工程,自己出去打工了。林某能请求法院撤销该赠与吗?
下列说法中符合施工现场要求的有()。
在后张法预应力中,张拉时结构中钢丝(束)、钢绞线断裂或滑脱的数量,严禁超过结构同一截面总根数的(),且一束钢丝只允许发生1根。
()不是我国当前资产管理行业需要主要关注的问题。
个人汽车贷款发放前,应落实的贷款发放条件不包括()。
甲公司为员工张某支付培训费用3万元,约定服务期3年。2年后,张某以公司自他入职起从未按照合同约定提供劳动保护为由,向单位提出解除劳动合同。以下说法正确的是()。
以优惠价出售日常家用小商品的零售商通常有上千雇员,其中大多数只能领取最低工资。随着国家法定的最低工资额的提高,零售商的人力成本也随之大幅度提高。但是零售商的利润非但没有降低,反而提高了。以下哪项如果为真,最有助于解释上述看起来矛盾的现象?
最新回复
(
0
)