『新东方在线托福阅读』为托福考生准备了ETS托福TPO/Official 7 Passage 1阅读练习：What is the main purpose of paragraph 3?真题题目及答案解析，TPO/Official 7 Passage 1阅读原文范文音频翻译

托福TPO/Official 7 Passage 1阅读原文What is the main purpose of paragraph 3?题目答案及解析-新东方托福官方网校手机版

The Geologic History of the Mediterranean

1970年，地质学家 Kenneth J.Hsu与William B.F.Ryan 一边收集研究数据，一边登上了格格玛·探索者号海洋科考船。

In 1970 geologists Kenneth J.Hsu and William B.F.Ryan were collecting research data while aboard the oceanographic research vessel Glomar Challenger.

这艘科考船其中一个目的是研究地中海海床，还有解决关于地质历史的问题。

An objective of this particular cruise was to investigate the floor of the Mediterranean and to resolve questions about its geologic history.

其中一个问题与无脊椎动物突变的证据相关，地中海的无脊椎动物在600万年前突然产生变化。

One question was related to evidence that the invertebrate fauna (animals without spines) of the Mediterranean had changed abruptly about 6 million years ago.

再古老一点的生物几乎全部灭绝，只有少数一些生命力顽强的物种存活了下来。

Most of the older organisms were nearly wiped out, although a few hardy species survived.

A few managed to migrate into the Atlantic.

不久之后，这些迁徙者又回到地中海，并且带回了新物种。

Somewhat later, the migrants returned, bringing new species with them.

为什么会出现这种几近灭绝的情况？又为什么会出现迁徙？

Why did the near extinction and migrations occur?

格格玛·探索者号上的科学家的另一个任务是尝试找到穹窿状巨块的起源，这些穹窿状巨块深埋在地中海海底。

Another task for the Glomar Challenger’s scientists was to try to determine the origin of the domelike masses buried deep beneath the Mediterranean seafloor.

数年前通过回声装置发现这些结构，但是它们从未被钻探过。

These structures had been detected years earlier by echo-sounding instruments, but they had never been penetrated in the course of drilling.

它们是不是含盐穹窿状巨块，就像美国海湾沿岸常见的那种？如果是的话，为什么地中海海底有如此多的固体结晶盐？

Were they salt domes such as are common along the United States Gulf Coast, and if so, why should there have been so much solid crystalline salt beneath the floor of the Mediterranean?

带着这些清楚摆在他们面前的问题，科学家们登上格格玛·探索者号前往地中海寻找答案。

With questions such as these clearly before them, the scientists aboard the Glomar Challenger proceeded to the Mediterranean to search for the answers.

在1970年8月23日，他们获得了一个样本。

On August 23, 1970, they recovered a sample.

这个样本包含一些砾石，这些砾石是硬化沉积物，这些沉积物原本是深海软泥，也有一些是石膏粒和火山岩碎块。

The sample consisted of pebbles of hardened sediment that had once been soft, deep-sea mud, as well as granules of gypsum and fragments of volcanic rock.

周围没能找到任何一块砾石表明它们来自附近的大陆。

Not a single pebble was found that might have indicated that the pebbles came from the nearby continent.

在接下来的时间里，随着钻探不断进行，海底固体石膏样本被不断打捞上甲板。

In the days following, samples of solid gypsum were repeatedly brought on deck as drilling operations penetrated the seafloor.

此外，这些石膏被发现有特有的成分与结构，表明了它们是在沙漠上形成的。

Furthermore, the gypsum was found to possess peculiarities of composition and structure that suggested it had formed on desert flats.

石膏层上下的沉积物都含有小的海洋生物化石，表明它们曾处在开阔的海洋环境中。

Sediment above and below the gypsum layer contained tiny marine fossils, indicating open-ocean conditions.

当他们钻到地中海盆地中间最深的地方时，科学家们从钻管中取出了固体的、闪亮的结晶盐。

As they drilled into the central and deepest part of the Mediterranean basin, the scientists took solid, shiny, crystalline salt from the core barrel.

跟结晶盐嵌在一起的还有一薄层看上去像风沙的东西。

Interbedded with the salt were thin layers of what appeared to be windblown silt.

The time had come to formulate a hypothesis.

研究者认为，大约2000万年前，地中海是片辽阔的大海，通过两个狭窄的海峡与大西洋相连。

The investigators theorized that about 20 million years ago, the Mediterranean was a broad seaway linked to the Atlantic by two narrow straits.

随着地壳运动，海峡消失了。地中海被陆地包围在内，也开始蒸发。

Crustal movements closed the straits, and the landlocked Mediterranean began to evaporate.

随着蒸发，地中海含盐量上升，导致数种无脊椎动物灭绝。

Increasing salinity caused by the evaporation resulted in the extermination of scores of invertebrate species.

只有少数一些耐高盐度的生物存活了下来。

Only a few organisms especially tolerant of very salty conditions remained.

随着海水持续的蒸发，剩下的盐水浓度如此之高以至于形成了硫酸钙硬层。

As evaporation continued, the remaining brine (salt water) became so dense that the calcium sulfate of the hard layer was precipitated.

在盆地中间更深的部分，最后的盐水蒸发了，产生了更多的可溶性氯化钠。

In the central deeper part of the basin, the last of the brine evaporated to precipitate more soluble sodium chloride (salt).

后来，在上层沉淀物的重压下，盐向上形成了含盐的圆顶。

Later, under the weight of overlying sediments, this salt flowed plastically upward to form salt domes.

在这之前，地中海是3000米深的沙漠。

Before this happened, however, the Mediterranean was a vast desert 3,000 meters deep.

然后，大约550万年前大洪水来临。

Then, about 5.5 million years ago came the deluge.

由于板块运动调整，现今联通地中海与大西洋的直布罗陀海峡被打开了，大量的水像瀑布一样涌入地中海。

As a result of crustal adjustments and faulting, the Strait of Gibraltar, where the Mediterranean now connects to the Atlantic, opened, and water cascaded spectacularly back into the Mediterranean.

汹涌的水撕裂了坚硬的含盐岩石，把它们磨成了砾石，也就是探索者号发现的第一个样本。

Turbulent waters tore into the hardened salt flats, broke them up, and ground them into the pebbles observed in the first sample taken by the Challenger.

随着盆地再次灌满水，普通海洋生物又回来了。

As the basin was refilled, normal marine organisms returned.

不久后海洋软泥层开始在原先的硬地层上堆积。

Soon layers of oceanic ooze began to accumulate above the old hard layer.

盐、石膏、动物区系的变更，还有不寻常的沙砾层都是地中海曾经是一片沙漠的证据。

The salt and gypsum, the faunal changes, and the unusual gravel provided abundant evidence that the Mediterranean was once a desert.

The word “objective” in the passage is closest in meaning to

Which of the following is NOT mentioned in paragraph 1 as a change that occurred in the fauna of the Mediterranean?

What does the author imply by saying “Not a single pebble was found that might have indicated that the pebbles came from the nearby continent”?

Which of the following can be inferred from paragraph 3 about the solid gypsum layer?

Select the TWO answer choices from paragraph 3 that identify materials discovered in the deepest part of the Mediterranean basin. To receive credit, you must select TWO answers.

According to paragraph 4, which of the following was responsible for the evaporation of the Mediterranean's waters?

According to paragraph 4, what caused most invertebrate species in the Mediterranean to become extinct?

Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.

Which of the following can be inferred from paragraph 4 about the salt domes in the Mediterranean?

The Geologic History of the Mediterranean In 1970 geologists Kenneth J. Hsu and William B. F. Ryan were collecting research data while aboard the oceanographic research vessel Glomar Challenger. An objective of this particular cruise was to investigate the floor of the Mediterranean and to resolve questions about its geologic history. One question was related to evidence that the invertebrate fauna (animals without spines) of the Mediterranean had changed abruptly about 6 million years ago. Most of the older organisms were nearly wiped out, although a few hardy species survived. A few managed to migrate into the Atlantic. Somewhat later, the migrants returned, bringing new species with them. Why did the near extinction and migrations occur? Another task for the Glomar Challenger’s scientists was to try to determine the origin of the domelike masses buried deep beneath the Mediterranean seafloor.  These structures had been detected years earlier by echo-sounding instruments, but they had never been penetrated in the course of drilling.  Were they salt domes such as are common along the United States Gulf Coast, and if so, why should there have been so much solid crystalline salt beneath the floor of the Mediterranean?  With questions such as these clearly before them, the scientists aboard the Glomar Challenger proceeded to the Mediterranean to search for the answers. On August 23, 1970, they recovered a sample. The sample consisted of pebbles of hardened sediment that had once been soft, deep-sea mud, as well as granules of gypsum and fragments of volcanic rock. Not a single pebble was found that might have indicated that the pebbles came from the nearby continent. In the days following, samples of solid gypsum were repeatedly brought on deck as drilling operations penetrated the seafloor. Furthermore, the gypsum was found to possess peculiarities of composition and structure that suggested it had formed on desert flats. Sediment above and below the gypsum layer contained tiny marine fossils, indicating open-ocean conditions. As they drilled into the central and deepest part of the Mediterranean basin, the scientists took solid, shiny, crystalline salt from the core barrel. Interbedded with the salt were thin layers of what appeared to be windblown silt. The time had come to formulate a hypothesis. The investigators theorized that about 20 million years ago, the Mediterranean was a broad seaway linked to the Atlantic by two narrow straits. Crustal movements closed the straits, and the landlocked Mediterranean began to evaporate. Increasing salinity caused by the evaporation resulted in the extermination of scores of invertebrate species. Only a few organisms especially tolerant of very salty conditions remained. As evaporation continued, the remaining brine (salt water) became so dense that the calcium sulfate of the hard layer was precipitated. In the central deeper part of the basin, the last of the brine evaporated to precipitate more soluble sodium chloride (salt). Later, under the weight of overlying sediments, this salt flowed plastically upward to form salt domes. Before this happened, however, the Mediterranean was a vast desert 3,000 meters deep. Then, about 5.5 million years ago came the deluge. As a result of crustal adjustments and faulting, the Strait of Gibraltar, where the Mediterranean now connects to the Atlantic, opened, and water cascaded spectacularly back into the Mediterranean. Turbulent waters tore into the hardened salt flats, broke them up, and ground them into the pebbles observed in the first sample taken by the Challenger. As the basin was refilled, normal marine organisms returned. Soon layers of oceanic ooze began to accumulate above the old hard layer. The salt and gypsum, the faunal changes, and the unusual gravel provided abundant evidence that the Mediterranean was once a desert.