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OFFICIAL51 It can be inferred from paragraph 2 that Earth evolved differently than Venus did in part because

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Surface Fluids on Venus and Earth
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A fluid is a substance, such as a liquid or gas, in which the component particles (usually molecules) can move past one another. Fluids flow easily and conform to the shape of their containers. The geologic processes related to the movement of fluids on a planet's surface can completely resurface a planet many times. These processes derive their energy from the Sun and the gravitational forces of the planet itself. As these fluids interact with surface materials, they move particles about or react chemically with them to modify or produce materials. On a solid planet with a hydrosphere and an atmosphere, only a tiny fraction of the planetary mass flows as surface fluids. Yet the movements of these fluids can drastically alter a planet. Consider Venus and Earth, both terrestrial planets with atmospheres.

Venus and Earth are commonly regarded as twin planets but not identical twins. They are about the same size, are composed of roughly the same mix of materials, and may have been comparably endowed at their beginning with carbon dioxide and water. However, the twins evolved differently largely because of differences in their distance from the Sun. With a significant amount of internal heat, Venus may continue to be geologically active with volcanoes, rifting, and folding. However, it lacks any sign of a hydrologic system (water circulation and distribution): there are no streams, lakes oceans or glaciers. Space probes suggest that Venus may have started with as much water as Earth, but it was unable to keep its water in liquid form. Because Venus receives more heat from the Sun, water released from the interior evaporated and rose to the upper atmosphere where the Sun's ultraviolet rays broke the molecules apart. Much of the freed hydrogen escaped into space, and Venus lost its water. Without water, Venus became less and less like Earth and kept an atmosphere filled with carbon dioxide. The carbon dioxide acts as a blanket, creating an intense greenhouse effect and driving surface temperatures high enough to melt lead and to prohibit the formation of carbonate minerals. Volcanoes continually vented more carbon dioxide into the atmosphere. On Earth, liquid water removes carbon dioxide from the atmosphere and combines it with calcium, from rock weathering, to form carbonate sedimentary rocks. Without liquid water to remove carbon from the atmosphere, the level of carbon dioxide in the atmosphere of Venus remains high.

Like Venus, Earth is large enough to be geologically active and for its gravitational field to hold an atmosphere. Unlike Venus, it is just the right distance from the Sun so that temperature ranges allow water to exist as a liquid, a solid, and a gas. Water is thus extremely mobile and moves rapidly over the planet in a continuous hydrologic cycle. Heated by the Sun, the water moves in great cycles from the oceans to the atmosphere, over the landscape in river systems, and ultimately back to the oceans. As a result, Earth's surface has been continually changed and eroded into delicate systems of river valleys - a remarkable contrast to the surfaces of other planetary bodies where impact craters dominate. Few areas on Earth have been untouched by flowing water. As a result, river valleys are the dominant feature of its landscape. Similarly, wind action has scoured fine particles away from large areas, depositing them elsewhere as vast sand seas dominated by dunes or in sheets of loess (fine-grained soil deposits). These fluid movements are caused by gravity flow systems energized by heat from the Sun. Other geologic changes occur when the gases in the atmosphere or water react with rocks at the surface to form new chemical compounds with different properties. An important example of this process was the removal of most of Earths carbon dioxide from its atmosphere to form carbonate rocks. However, if Earth were a little closer to the Sun, its oceans would evaporate; if it were farther from the Sun, the oceans would freeze solid. Because liquid water was present, self-replicating molecules of carbon, hydrogen, and oxygen developed life early in Earth's history and have radically modified its surface, blanketing huge parts of the continents with greenery. Life thrives on this planet, and it helped create the planet's oxygen- and nitrogen-rich atmosphere and moderate temperatures.

6.It can be inferred from paragraph 2 that Earth evolved differently than Venus did in part because

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【题目翻译】从第2段可以推断出,地球的进化与金星的不同部分是因为 A:早期金星上的火山活动比早期地球上的多。 B:它们收到了不同数量的太阳能。 C:它们的内部含有不同量的热量。 D:它们早期的大气含有不同水平的氧气和氮。 【判定题型】:根据题干中出现的关键词“imply”/“infer”/“suggest”等其他表示推断的词,判定本题为推理题。 【关键词定位】根据题干中关键词“evolved differently”,定位到第二段中这句话“However, the twins evolved differently largely because of differences in their distance from the Sun.” 【逻辑分析】题目问地球与金星演变方式不同的其中一个原因是?由此得出,与太阳之间距离的不同,是导致它们演变方式不同的最主要原因。但是没有这个选项。那么我们就要推测,与太阳距离的不同,会导致什么结果?因为金星离太阳更近,所以它吸收更多热量,而地球与太阳距离适中,温度也较适宜。所以与太阳距离的不同,会导致2个星期温度的不同。而温度的不同,会直接决定行星上是否存在水,间接决定行星地貌。 【选项分析】 A选项:金星早期的火山活动比地球早期要更多。文章只提到金星上火山活动频繁,没有将其和地球作比较,A排除。 B选项:它们吸收的太阳能量不同,是正确答案。 C选项:它们所含的内部能量不同。文中未提及。C选项排除。 D选项:它们早期含有不同水平的氧和氮。第二段只提到“Space probes suggest that Venus may have started with as much water as Earth, but ……”金星和地球早期都含有水,但没提到氧气和氮气含量,故D选项未提及,排除。

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