2012年4月28日托?？荚囃瑯又噩F(xiàn)了北美機(jī)經(jīng)的題目。本文為您提供托福閱讀翻譯及詳細(xì)答案解析：地下水。
4.28托福閱讀翻譯：地下水
地下水是指滲入到地下并將所有巖石空隙填滿的水。到現(xiàn)在為止，雨水是最豐富的地下水資源，是地下水在水循環(huán)中的一個(gè)環(huán)節(jié)。普通的雨水會(huì)從地表、降水以及湖泊河流侵入到地下。在冒出地表之前，這些地下水有時(shí)會(huì)長時(shí)間留在地下。在我們腳下堅(jiān)實(shí)的土地中竟然有足夠的空間儲(chǔ)存這些水，這在一開始會(huì)讓人覺得難以置信。
地下水所需的儲(chǔ)存空間多種多樣。松散的砂子和礫石間有許多顆粒和小石子，他們之間的空隙是最常見的儲(chǔ)存地下水的空間。由這些顆粒組成的水床非常普遍，通常位于看不見的土壤下方，在湍急的河流曾經(jīng)流過的地方都能找到它們的蹤跡。比如，冰河時(shí)代覆蓋北美的巨大冰層逐漸融化，大量水從那兒流出。水里總會(huì)攜帶些石子、礫石和沙石，這就是所謂的冰河期的冰水沉積，這些顆粒會(huì)隨著水流的減速而沉淀。
現(xiàn)代也有冰水沉積，盡管規(guī)模相對(duì)較小。凡是有攜帶泥沙的河流或者溪流從山谷流至相對(duì)平坦的地面時(shí)，砂石就隨著水流速度的減慢逐漸沉淀;水流通常呈扇形擴(kuò)散，它們所攜帶的砂石也會(huì)沉淀為光滑的扇形斜面。當(dāng)河流匯入湖泊和海洋的時(shí)候也會(huì)有沉淀，這些沉淀最初在湖底或海底，但將來海平面下降或者陸地崛起時(shí)，它們就會(huì)分布于內(nèi)陸，通常厚達(dá)幾千米。
低地區(qū)域上的任何位置可能就是曾經(jīng)的河床，后續(xù)被土壤覆蓋而變成現(xiàn)在的樣子。如果那些河床和沙洲現(xiàn)在位于地下水位之下，一定會(huì)有大量的地下水浸在它們的沙礫和沙石之間。
以上說的都是松散的沉積物，那些堅(jiān)固的沉積物，也擁有以數(shù)萬計(jì)的毛細(xì)孔來容納水。因?yàn)樽畛躅w粒間的縫隙通常并未完全被粘固的化學(xué)物質(zhì)塞滿，而且部分顆粒很可能在固化時(shí)或固化后被滲入的地下水溶解;結(jié)果這些砂巖最終變得和形成它的散沙一樣多孔。
因此，不管沉積物是疏松還是堅(jiān)固，他們中一定有空間。大部分結(jié)晶體巖石都非常堅(jiān)硬，但也有例外，最常見的就是玄武巖，它是一種固化的火山熔巖，經(jīng)常充滿了微小氣泡，從而變得十分多孔。
巖石的多孔性就是指其中空隙的比例。但需要注意的是，多孔性與滲透性是不同的。滲透性衡量的是水滲透物質(zhì)的難易程度，它取決于與單個(gè)空隙以及連接空隙間裂縫的大小。
當(dāng)充滿水分的沉淀物或者巖石樣本被放置在適合的干燥環(huán)境中時(shí)，大部分的水分會(huì)流干，但仍有部分水會(huì)繼續(xù)附著在堅(jiān)實(shí)的表面上。要不是因?yàn)楸砻鎻埩?，這些水分也會(huì)立刻蒸發(fā)，僅留下完全干燥的樣本。因此，試驗(yàn)樣本的含水量既包括可以流干的水，也包括不能流干的水。
這兩種水的相對(duì)含量因巖石或沉積物種類不同而改變，即便它們有相同比例的空隙，還取決于空隙的大小。如果空隙很大，其中的水會(huì)形成水滴，太重足以克服吸引它的表面張力，就會(huì)流走;但如果空隙夠小，水會(huì)像薄膜一樣，太輕無法克服表面張力，從而穩(wěn)穩(wěn)地附著在空隙表面上。
文章逐句翻譯
第一段：
Groundwater is the word used to describe water that saturates the ground, filling all the available spaces.
地下水是指滲入地下并填滿巖石空隙的水。
By far the most abundant type of groundwater is meteoric water; this is the groundwater that circulates as part of the water cycle.
至今為止最豐富的地下水來源便是氣象水，它是自然界水循環(huán)的一部分。
Ordinary meteoric water is water that has soaked into the ground from the surface, from precipitation (rain and snow) and from lakes and streams.
普通氣象水會(huì)從地表、雨雪湖泊和河川滲入地下。
There it remains, sometimes for long periods, before emerging at the surface again.
有時(shí)它們會(huì)長時(shí)間滯留于此，之后再次涌出地表。
At first thought it seems incredible that there can be enough space in the “solid” ground underfoot to hold all this water.
或許在人們看來，堅(jiān)硬的地殼居然有充足空間來儲(chǔ)存這樣多的水是難以置信的。
第二段：
The necessary space is there, however, in many forms.
然而，地下水的儲(chǔ)存空間是多種多樣的。
The commonest spaces are those among the particles—sand grains and tiny pebbles—of loose, unconsolidated sand and gravel.
最常見的便是疏松砂石中的細(xì)小顆粒----如沙粒和小鵝卵石----之間的空隙。
Beds of this material, out of sight beneath the soil, are common. They are found wherever fast rivers carrying loads of coarse sediment once flowed.
這些砂石床藏匿于土壤之下，極為普遍，凡是那些負(fù)載著粗糙沉積物的湍急河流流經(jīng)之處都可以發(fā)現(xiàn)它們的蹤跡。
For example, as the great ice sheets that covered North America during the last ice age steadily
melted away, huge volumes of water flowed from them.
比如，隨著冰河時(shí)代覆蓋北美的巨大冰層逐漸融化，大量融水洶涌流出。
The water was always laden with pebbles, gravel, and sand, known as glacial outwash, that was deposited as the flow slowed down.
水中會(huì)攜帶鵝卵石、礫石和沙石，即所謂的冰水沉積物，它們會(huì)隨水流漸緩而緩慢沉淀。
第三段：
The same thing happens to this day, though on a smaller scale,
類似事件如今也時(shí)常發(fā)生，不過規(guī)模相對(duì)較小罷了。
wherever a sediment-laden river or stream emerges from a mountain valley onto relatively flat land, dropping its load as the current slows: the water usually spreads out fanwise, depositing the sediment in the form of a smooth, fan-shaped slope.
當(dāng)攜帶沉積物的河流或溪水從山谷而下，流至相對(duì)平坦的地面時(shí)，砂石便隨著流速減慢而逐漸沉淀：水流通常呈扇形蔓延，進(jìn)而使所承載的砂石以光滑扇形的斜面形式沉積下來。Sediments are also dropped where a river slows on entering a lake or the sea, the deposited sediments are on a lake floor or the seafloor at first, but will be located inland at some future date, when the sea level falls or the land rises; such beds are sometimes thousands of meters thick.
當(dāng)河流匯入湖泊和海洋時(shí)也會(huì)留下沉積物，這些沉淀物最初附著在湖底或海底，但日后一旦海平面下降或者陸地崛起，它們便會(huì)分布至內(nèi)陸，厚度通常達(dá)幾千米。
第四段：
In lowland country almost any spot on the ground may overlie what was once the bed of a river that has since become buried by soil;
在低地國家，任何一寸土地之下都可能存在曾經(jīng)河流的河床，這些河流被土壤掩埋而消失。
if they are now below the water’s upper surface (the water table), the gravels and sands of the former riverbed, and its sandbars, will be saturated with groundwater.
如果這些河床如今正位于地下水位之下，那麼其所含的沙石定會(huì)儲(chǔ)存了大量地下水。
第五段：
So much for unconsolidated sediments. Consolidated (or cemented) sediments, too, contain millions of minute water-holding pores.
上述內(nèi)容都是有關(guān)松散沉積物的儲(chǔ)水狀況，而堅(jiān)固沉積物同樣也擁有以數(shù)萬計(jì)的微孔來容納水分。
This is because the gaps among the original grains are often not totally plugged with cementing chemicals;
這是由于最初沙粒的縫隙通常并沒有被膠黏質(zhì)的化學(xué)物質(zhì)完全阻塞，
also, parts of the original grains may become dissolved by percolating groundwater, either while consolidation is taking place or at any time afterwards.
同時(shí)，部分顆粒很可能在固化或者固化之后被滲透而下的地下水溶解。
The result is that sandstone, for example, can be as porous as the loose sand from which it was formed.
最終，如由散沙形成的砂巖甚至?xí)兊煤蜕⑸骋粯佣嗫住?BR> 第六段：
Thus a proportion of the total volume of any sediment, loose or cemented, consists of empty space. 因此，無論沉積物屬于疏松或是堅(jiān)固，其整體中必有一部分為真空區(qū)。
Most crystalline rocks are much more solid; a common exception is basalt, a form of solidified volcanic lava, which is sometimes full of tiny bubbles that make it very porous.
大部分巖石晶體都非常堅(jiān)硬，不過也有例外，如玄武巖。它是一種固化的火山熔巖，內(nèi)部經(jīng)常充滿微小氣泡，從而變得十分多孔。
第七段：
The proportion of empty space in a rock is known as its porosity.
巖石真空區(qū)比例的大小被稱為多孔性。
But note that porosity is not the same as permeability, which measures the ease with which water can flow through a material; this depends on the sizes of the individual cavities and the crevices linking them.
但注意，多孔性與滲透性是不同概念。滲透性衡量的是水滲透物質(zhì)的難易程度，它取決于物質(zhì)中獨(dú)立孔洞以及連接孔洞的裂縫的大小。
第八段
Much of the water in a sample of water-saturated sediment or rock will drain from it if the sample is put in a suitable dry place.
當(dāng)浸滿水分的沉淀物或者巖石樣本被放在適宜的干燥環(huán)境中時(shí)，大部分水分會(huì)蒸發(fā)。
But some will remain, clinging to all solid surfaces.
但仍有部分水分會(huì)繼續(xù)附著在樣本的表面。
It is held there by the force of surface tension without which water would drain instantly from any wet surface, leaving it totally dry.
這是由于水的表面張力使水分得以存留，否則樣本將迅速完全干燥。
The total volume of water in the saturated sample must therefore be thought of as consisting of water that can, and water that cannot, drain away.
因此，試驗(yàn)樣本的含水量包含兩部分，可被蒸發(fā)的水和不可被蒸發(fā)的水。
第九段：
The relative amount of these two kinds of water varies greatly from one kind of rock or sediment to another, even though their porosities may be the same. What happens depends on pore size.
這兩種水分的相對(duì)含量因巖石與沉積物種類不同而不同，即便它們的孔隙度相同也是如此。毛孔的大小決定了它們的比例。
If the pores are large, the water in them will exist as drops too heavy for surface tension to hold, and it will drain away;
如果毛孔很大，毛孔中的水會(huì)形成過重的水滴，進(jìn)而可以克服表面張力，從而掉落。
but if the pores are small enough, the water in them will exist as thin films, too light to overcome the force of surface tension holding them in place; then the water will be firmly held.
但如果毛孔足夠小，其中的水會(huì)像薄膜一樣，由于過輕而無法克服吸引它的表面張力，從而被穩(wěn)固的吸附在孔隙中。
4.28托福閱讀翻譯：地下水
地下水是指滲入到地下并將所有巖石空隙填滿的水。到現(xiàn)在為止，雨水是最豐富的地下水資源，是地下水在水循環(huán)中的一個(gè)環(huán)節(jié)。普通的雨水會(huì)從地表、降水以及湖泊河流侵入到地下。在冒出地表之前，這些地下水有時(shí)會(huì)長時(shí)間留在地下。在我們腳下堅(jiān)實(shí)的土地中竟然有足夠的空間儲(chǔ)存這些水，這在一開始會(huì)讓人覺得難以置信。
地下水所需的儲(chǔ)存空間多種多樣。松散的砂子和礫石間有許多顆粒和小石子，他們之間的空隙是最常見的儲(chǔ)存地下水的空間。由這些顆粒組成的水床非常普遍，通常位于看不見的土壤下方，在湍急的河流曾經(jīng)流過的地方都能找到它們的蹤跡。比如，冰河時(shí)代覆蓋北美的巨大冰層逐漸融化，大量水從那兒流出。水里總會(huì)攜帶些石子、礫石和沙石，這就是所謂的冰河期的冰水沉積，這些顆粒會(huì)隨著水流的減速而沉淀。
現(xiàn)代也有冰水沉積，盡管規(guī)模相對(duì)較小。凡是有攜帶泥沙的河流或者溪流從山谷流至相對(duì)平坦的地面時(shí)，砂石就隨著水流速度的減慢逐漸沉淀;水流通常呈扇形擴(kuò)散，它們所攜帶的砂石也會(huì)沉淀為光滑的扇形斜面。當(dāng)河流匯入湖泊和海洋的時(shí)候也會(huì)有沉淀，這些沉淀最初在湖底或海底，但將來海平面下降或者陸地崛起時(shí)，它們就會(huì)分布于內(nèi)陸，通常厚達(dá)幾千米。
低地區(qū)域上的任何位置可能就是曾經(jīng)的河床，后續(xù)被土壤覆蓋而變成現(xiàn)在的樣子。如果那些河床和沙洲現(xiàn)在位于地下水位之下，一定會(huì)有大量的地下水浸在它們的沙礫和沙石之間。
以上說的都是松散的沉積物，那些堅(jiān)固的沉積物，也擁有以數(shù)萬計(jì)的毛細(xì)孔來容納水。因?yàn)樽畛躅w粒間的縫隙通常并未完全被粘固的化學(xué)物質(zhì)塞滿，而且部分顆粒很可能在固化時(shí)或固化后被滲入的地下水溶解;結(jié)果這些砂巖最終變得和形成它的散沙一樣多孔。
因此，不管沉積物是疏松還是堅(jiān)固，他們中一定有空間。大部分結(jié)晶體巖石都非常堅(jiān)硬，但也有例外，最常見的就是玄武巖，它是一種固化的火山熔巖，經(jīng)常充滿了微小氣泡，從而變得十分多孔。
巖石的多孔性就是指其中空隙的比例。但需要注意的是，多孔性與滲透性是不同的。滲透性衡量的是水滲透物質(zhì)的難易程度，它取決于與單個(gè)空隙以及連接空隙間裂縫的大小。
當(dāng)充滿水分的沉淀物或者巖石樣本被放置在適合的干燥環(huán)境中時(shí)，大部分的水分會(huì)流干，但仍有部分水會(huì)繼續(xù)附著在堅(jiān)實(shí)的表面上。要不是因?yàn)楸砻鎻埩?，這些水分也會(huì)立刻蒸發(fā)，僅留下完全干燥的樣本。因此，試驗(yàn)樣本的含水量既包括可以流干的水，也包括不能流干的水。
這兩種水的相對(duì)含量因巖石或沉積物種類不同而改變，即便它們有相同比例的空隙，還取決于空隙的大小。如果空隙很大，其中的水會(huì)形成水滴，太重足以克服吸引它的表面張力，就會(huì)流走;但如果空隙夠小，水會(huì)像薄膜一樣，太輕無法克服表面張力，從而穩(wěn)穩(wěn)地附著在空隙表面上。
文章逐句翻譯
第一段：
Groundwater is the word used to describe water that saturates the ground, filling all the available spaces.
地下水是指滲入地下并填滿巖石空隙的水。
By far the most abundant type of groundwater is meteoric water; this is the groundwater that circulates as part of the water cycle.
至今為止最豐富的地下水來源便是氣象水，它是自然界水循環(huán)的一部分。
Ordinary meteoric water is water that has soaked into the ground from the surface, from precipitation (rain and snow) and from lakes and streams.
普通氣象水會(huì)從地表、雨雪湖泊和河川滲入地下。
There it remains, sometimes for long periods, before emerging at the surface again.
有時(shí)它們會(huì)長時(shí)間滯留于此，之后再次涌出地表。
At first thought it seems incredible that there can be enough space in the “solid” ground underfoot to hold all this water.
或許在人們看來，堅(jiān)硬的地殼居然有充足空間來儲(chǔ)存這樣多的水是難以置信的。
第二段：
The necessary space is there, however, in many forms.
然而，地下水的儲(chǔ)存空間是多種多樣的。
The commonest spaces are those among the particles—sand grains and tiny pebbles—of loose, unconsolidated sand and gravel.
最常見的便是疏松砂石中的細(xì)小顆粒----如沙粒和小鵝卵石----之間的空隙。
Beds of this material, out of sight beneath the soil, are common. They are found wherever fast rivers carrying loads of coarse sediment once flowed.
這些砂石床藏匿于土壤之下，極為普遍，凡是那些負(fù)載著粗糙沉積物的湍急河流流經(jīng)之處都可以發(fā)現(xiàn)它們的蹤跡。
For example, as the great ice sheets that covered North America during the last ice age steadily
melted away, huge volumes of water flowed from them.
比如，隨著冰河時(shí)代覆蓋北美的巨大冰層逐漸融化，大量融水洶涌流出。
The water was always laden with pebbles, gravel, and sand, known as glacial outwash, that was deposited as the flow slowed down.
水中會(huì)攜帶鵝卵石、礫石和沙石，即所謂的冰水沉積物，它們會(huì)隨水流漸緩而緩慢沉淀。
第三段：
The same thing happens to this day, though on a smaller scale,
類似事件如今也時(shí)常發(fā)生，不過規(guī)模相對(duì)較小罷了。
wherever a sediment-laden river or stream emerges from a mountain valley onto relatively flat land, dropping its load as the current slows: the water usually spreads out fanwise, depositing the sediment in the form of a smooth, fan-shaped slope.
當(dāng)攜帶沉積物的河流或溪水從山谷而下，流至相對(duì)平坦的地面時(shí)，砂石便隨著流速減慢而逐漸沉淀：水流通常呈扇形蔓延，進(jìn)而使所承載的砂石以光滑扇形的斜面形式沉積下來。Sediments are also dropped where a river slows on entering a lake or the sea, the deposited sediments are on a lake floor or the seafloor at first, but will be located inland at some future date, when the sea level falls or the land rises; such beds are sometimes thousands of meters thick.
當(dāng)河流匯入湖泊和海洋時(shí)也會(huì)留下沉積物，這些沉淀物最初附著在湖底或海底，但日后一旦海平面下降或者陸地崛起，它們便會(huì)分布至內(nèi)陸，厚度通常達(dá)幾千米。
第四段：
In lowland country almost any spot on the ground may overlie what was once the bed of a river that has since become buried by soil;
在低地國家，任何一寸土地之下都可能存在曾經(jīng)河流的河床，這些河流被土壤掩埋而消失。
if they are now below the water’s upper surface (the water table), the gravels and sands of the former riverbed, and its sandbars, will be saturated with groundwater.
如果這些河床如今正位于地下水位之下，那麼其所含的沙石定會(huì)儲(chǔ)存了大量地下水。
第五段：
So much for unconsolidated sediments. Consolidated (or cemented) sediments, too, contain millions of minute water-holding pores.
上述內(nèi)容都是有關(guān)松散沉積物的儲(chǔ)水狀況，而堅(jiān)固沉積物同樣也擁有以數(shù)萬計(jì)的微孔來容納水分。
This is because the gaps among the original grains are often not totally plugged with cementing chemicals;
這是由于最初沙粒的縫隙通常并沒有被膠黏質(zhì)的化學(xué)物質(zhì)完全阻塞，
also, parts of the original grains may become dissolved by percolating groundwater, either while consolidation is taking place or at any time afterwards.
同時(shí)，部分顆粒很可能在固化或者固化之后被滲透而下的地下水溶解。
The result is that sandstone, for example, can be as porous as the loose sand from which it was formed.
最終，如由散沙形成的砂巖甚至?xí)兊煤蜕⑸骋粯佣嗫住?BR> 第六段：
Thus a proportion of the total volume of any sediment, loose or cemented, consists of empty space. 因此，無論沉積物屬于疏松或是堅(jiān)固，其整體中必有一部分為真空區(qū)。
Most crystalline rocks are much more solid; a common exception is basalt, a form of solidified volcanic lava, which is sometimes full of tiny bubbles that make it very porous.
大部分巖石晶體都非常堅(jiān)硬，不過也有例外，如玄武巖。它是一種固化的火山熔巖，內(nèi)部經(jīng)常充滿微小氣泡，從而變得十分多孔。
第七段：
The proportion of empty space in a rock is known as its porosity.
巖石真空區(qū)比例的大小被稱為多孔性。
But note that porosity is not the same as permeability, which measures the ease with which water can flow through a material; this depends on the sizes of the individual cavities and the crevices linking them.
但注意，多孔性與滲透性是不同概念。滲透性衡量的是水滲透物質(zhì)的難易程度，它取決于物質(zhì)中獨(dú)立孔洞以及連接孔洞的裂縫的大小。
第八段
Much of the water in a sample of water-saturated sediment or rock will drain from it if the sample is put in a suitable dry place.
當(dāng)浸滿水分的沉淀物或者巖石樣本被放在適宜的干燥環(huán)境中時(shí)，大部分水分會(huì)蒸發(fā)。
But some will remain, clinging to all solid surfaces.
但仍有部分水分會(huì)繼續(xù)附著在樣本的表面。
It is held there by the force of surface tension without which water would drain instantly from any wet surface, leaving it totally dry.
這是由于水的表面張力使水分得以存留，否則樣本將迅速完全干燥。
The total volume of water in the saturated sample must therefore be thought of as consisting of water that can, and water that cannot, drain away.
因此，試驗(yàn)樣本的含水量包含兩部分，可被蒸發(fā)的水和不可被蒸發(fā)的水。
第九段：
The relative amount of these two kinds of water varies greatly from one kind of rock or sediment to another, even though their porosities may be the same. What happens depends on pore size.
這兩種水分的相對(duì)含量因巖石與沉積物種類不同而不同，即便它們的孔隙度相同也是如此。毛孔的大小決定了它們的比例。
If the pores are large, the water in them will exist as drops too heavy for surface tension to hold, and it will drain away;
如果毛孔很大，毛孔中的水會(huì)形成過重的水滴，進(jìn)而可以克服表面張力，從而掉落。
but if the pores are small enough, the water in them will exist as thin films, too light to overcome the force of surface tension holding them in place; then the water will be firmly held.
但如果毛孔足夠小，其中的水會(huì)像薄膜一樣，由于過輕而無法克服吸引它的表面張力，從而被穩(wěn)固的吸附在孔隙中。