首页
登录
职称英语
In Death Valley, California, one of the hottest, most arid places in North Am
In Death Valley, California, one of the hottest, most arid places in North Am
游客
2024-01-04
13
管理
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 openings 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. [br] 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
转载请注明原文地址:https://tihaiku.com/zcyy/3332548.html
相关试题推荐
Whatdoesthetourguidetellhertourgroupabouteachofthefollowingplaces
Whatdoesthetourguidetellhertourgroupabouteachofthefollowingplaces
Whatdoesthetourguidetellhertourgroupabouteachofthefollowingplaces
(In)June,1846,(near)Sacramento,California,a(number)ofnewsettlersrebel
InDeathValley,California,oneofthehottest,mostaridplacesinNorthAm
InDeathValley,California,oneofthehottest,mostaridplacesinNorthAm
InDeathValley,California,oneofthehottest,mostaridplacesinNorthAm
InDeathValley,California,oneofthehottest,mostaridplacesinNorthAm
InDeathValley,California,oneofthehottest,mostaridplacesinNorthAm
CancerandChemicalsLastyear,CaliforniagovernorGeorgeD
随机试题
商标相同或近似的判定应当遵循()原则综合判断。A.以相关公众的一般注意力为标准进
Eveniffamiliesdon’tsitdowntoeat
《中华人民共和国国家赔偿法》是在哪一年正式通过的,标志着我国正式全面实施政府侵权
患者,男,12岁。大便水泻,并见轻微发热,恶心欲吐症状。舌质淡,舌苔白腻,脉象濡
关于甘味,下面说法不正确的是A.气虚中满者慎用B.湿阻者多用C.食积者慎用D.多
2020年7月限额以下单位餐饮收入占餐饮收入零售总额的比重约为:A.22.6
“江山易改,本性难移”说明了人格的()。A.独特性 B.整体性 C.
李老师针对已有教学方法的不足,提出了较为完善的情景教学方法,并取得了一定的成效。
在Word中,下列操作不能实现的是()。A.在页眉中插入日期B.建立奇偶页内
夸美纽斯教学论的基础是()。 A.心理学统觉论B.伦理学 C.整体认识论
最新回复
(
0
)