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Scientists generally credit violent collisions between tectonic plates, the mobilefragments of Earth's rocky outer shell, with sculpting the planet's surface, as, for example, when what is now the Indian subcontinent collided with Asia, producing the Himalayan Mountains. However, plate tectonics cannot fully explain certain massive surface features, such as the "superswell" of southern Africa, a vast plateau over 1,000 miles across and nearly a mile high. Geologic evidence shows that southern African has been slowly rising for the past 100 million years, yet it has not experienced a tectonic collision for nearly 400 million years. The explanation may be in Earth's mantle, the layer of rock underlying the tectonic plates and extending down over 1,800 miles to the outer edge of Earth's iron core.
Since the early twentieth century, geophysicists have understood that the mantle churns and roils like a thick soup. The relative low density of the hottest rock makes that material buoyant, so it slowly ascends, while cooler, denser rock sinks until heat escaping the molten core warms it enough to make it rise again. While this process of convection was known to enable the horizontal movement of tectonic plates, until recently geophysicists were skeptical of its ability to lift or lower the planet's surface vertically. However, recent technological advances have allowed geophysicists to make three-dimensional "snapshots" of the mantle by measuring vibrations, or seismic waves, set in motion by earthquakes originating in the planet's outer shell and recording the time it takes for them to travel from an earthquake's epicenter to a particular recording station at the surface. Because geophysicists know that seismic waves become sluggish in hot, low-density rock, and speed up in colder, denser regions, they can now infer the temperatures and den- sities in a given segment of the interior. By compiling a map of seismic velocities from thousands of earthquakes across the globe, they can also begin to map temperatures and densities throughout the mantle. These methods have revealed some unexpectedly immense for- mations in the deepest parts of the mantle; the largest of these is a buoyant mass of hot rock directly below Africa's southern tip. Dispelling researchers' initial doubts, computer models have confirmed that this formation is buoyant enough to rise slowly within the mantle and strong enough to push Africa upward as it rises.
According to the passage, the computer models(highlight text) referred to have had which of the following effects?
They have confirmed researchers' doubts regarding the theory that convection within the mantle can lift or lower Earth's surface vertically.
They have cast doubt on the validity of plate-tectonics theory as an explanation for the sculpting of Earth's mountain ranges.
They have proved geophysicists' theory that the behavior of seismic waves in Earth's mantle is related to the temperature of the rock through which they are traveling.
They have convinced formerly skeptical researchers that rock formations deep in Earth's mantle below southern Africa could have created the superswell.
They have confirmed researchers' speculation that masses of hot rock are buoyant enough to rise to the upper part of Earth's mantle.
此讲解的内容由AI生成，还未经人工审阅，仅供参考。
正确答案是D。之所以选择D，是因为文章提到，最近的技术进步让地球物理学家可以通过测量由地球外壳中的地震产生的震动或地震波，来对地幔进行三维快照，并且根据地震波变慢的热低密度岩石和加速的冷高密度岩石获得其温度和密度。电脑模型证明了研究人员最初的怀疑，即非洲南部以下的熔岩内的岩石形成物足够浮力上升到地球的上部地幔中，从而产生了超级涌升层（superswell）。
错选A, 不是confirm doubt而是dispell doubt驱散怀疑
confirm doubt应该也是证实一个怀疑其实意思差不多，就是把一个怀疑确定，A应该是错在vertically
sorry，我看了一下，是我错了 ; p 一个是证实怀疑，一个是 使怀疑着者信服
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E：不是mantle上升，是Africa上升
去第一段找“superswell”这个词，可以确认D是对的。同时全文最后一句“ strong enough to push Africa upward as it rises.”可以确认E选项的rise对象错了
我就想表示我考试碰到类似的估计也还是错
错选E，原文说的是omputer models have confirmed that this formation is buoyant enough to rise slowly within the mantle and strong enough to push Africa upward as it rises.有足够的浮力在地幔内部缓慢上升，并且有足够的力量在它上升的同时推动非洲上升。，选项说的是大量的热岩石有足够的浮力上升到地幔上部。
正确D，
回到第一段，可以发现文章就是在讲superswell到底由什么引起，错选E，E选项原文是push Africa upward 而不是 upper part of Earth's mantle
confirmed researchers' doubts = 证实了研究人员的怀疑
convinced formerly skeptical researchers = 使之前怀疑的研究人员相信
A.他们证实了研究人员对地幔内部对流可以垂直抬升或降低地球表面的理论的怀疑。
D.他们已经让以前持怀疑态度的研究人员相信，非洲南部地下地幔深处的岩层可能创造了superwell.
没注意问题里面的细节词语!!不是confirm doubt.
做CR也经常错这个
E: 最后一句说 raise "within" the mantle, 不是 to the upper part of the mantel
A: dispute the doubts
C: 对的， 最后一句 strong enough to push Africa raise
a & e?选d的核心是不是在formation，因为是形成的过程是漂浮的猜形成了那些很大的变动。
定位最后一句：[Dispelling researchers' initial doubts], computer models have confirmed that this formation is buoyant enough to rise slowly within the mantle and strong enough to push Africa upward as it rises.
confirm doubt证实怀疑；dispell doubt驱散怀疑（使怀疑着者信服）
计算机模型是驱散了研究人员最初的怀疑，这个doubt定位在；While this process of convection was known to enable the "horizontal" movement of tectonic plates, until recently geophysicists were [skeptical] of its ability to lift or lower the planet's surface "vertically".
高亮部分的目的是dispelling researchers' initial doubts，而initial doubts对应了第一段however之后的内容，具体定位至科学家的假定explanation：“The explanation may be in Earth's mantle, the layer of rock underlying the tectonic plates and extending down over 1,800 miles to the outer edge of Earth's iron core.”
高亮部分的目的是dispelling researchers' initial doubts，而initial doubts对应了第一段however之后的内容，具体定位至科学家的假定explanation：“The explanation may be in Earth's mantle, the layer of rock underlying the tectonic plates and extending down over 1,800 miles to the outer edge of Earth's iron core.”
until recently geophysicists were skeptical of its ability to lift or lower the planet's surface vertically.
原文第二段第三句原话 Researchers are“ #keptical# of its ability to lift or lower the planet's surface vertically“ ，和D的“skeptical”一致；原文并没有提到过speculate, 所以E里说speculation是错的
AB. 都是提出这个怀疑
C. 与theory无关
D. 解释了第一段最后的疑问
E. 是hot rock rise “within the mantle”并且使Africa上升，而不是hot rock 上升到mantle的上部
既然是打消了initial doubts，那么定位肯定是在第一段与Africa有关的内容
E的enough to rise to the upper...错了，原文最后一句是to push Africa...
细节看丢，要定位
d。superswell指的就是第一段的
e。hot rock are buoyant enough to rise to the upper part of Earth's mantle错，不是mantle升，是push地表的Africa upward
错选E
E选项原文是push Africa upward 而不是 upper part of Earth's mantle