gwd7-Q22 to Q25

slamshady

请问24题答案到底是D还是E？
我觉得D有问题：distance from plate edges在文章中好像与夏威夷火山并无太大关系，文章讨论的是板块在plume上移动的距离，而不是火山到板块边缘的距离

Outsider1988

这篇阅读讨论了好久啊
。。。

gedn01

Earth’s surface consists of rigid plates that are constantly shifting and jostling one another.  late movements are the surface expressions of motions in the mantle—the thick shell of rock that lies between Earth’s crust and its metallic core.  Although the hot rock of the mantle is a solid, under the tremendous pressure of the crust and overlying rock of the mantle, it flows like a viscous liquid.  The mantle’s motions, analogous to those in a pot of boiling water, cool the mantle by carrying hot material to the surface and returning cooler material to the depths.  When the edge of one plate bends under another and its cooler material is consumed in the mantle, volcanic activity occurs as molten lava rises from the downgoing plate and erupts through the overlying one.
     Most volcanoes occur at plate boundaries.  However, certain “misplaced” volcanoes far from plate edges result from a second, independent mechanism that cools the deep interior of Earth.  Because of its proximity to Earth’s core, the rock at the base of the mantle is much hotter than rock in the upper mantle.  The hotter the mantle rock is, the less it resists flowing.  Reservoirs of this hot rock collect in the base of the mantle. When a reservoir is sufficiently large, a sphere of this hot rock forces its way up through the upper mantle to Earth’s surface, creating a broad bulge in the topography.  The “mantle plume” thus formed, once established, continues to channel hot material from the mantle base until the reservoir is emptied. The surface mark of an established plume is a hot spot—an isolated region of volcanoes and uplifted terrain located far from the edge of a surface plate.  Because the source of a hot spot remains fixed while a surface plate moves over it, over a long period of time an active plume creates a chain of volcanoes or volcanic islands, a track marking the position of the plume relative to the moving plate.  The natural history of the Hawaiian island chain clearly shows the movement of the Pacific plate over a fixed plume.

Q24:
The author’s reference to the Hawaiian Islands serves primarily to
B.identify the evidence initially used to establish that the Pacific plate moves
E.provide an example of how mantle plumes manifest themselves on Earth’s surface
B与E，谁对谁错?

Vevey

文章完全读懂以后，才能发现原来所有给的答案都是那么准确。。反复读文章知道自己可以模拟那个火山形成的过程。

gigi68788

确实好难好难～看了那么多讨论之后才多明白一点，但还是觉得难。再出一篇类似的，估计也难做到阿～

逆水潜龙

24选E，其实很容易和B区分。
举例就是为了解释前一句，a track marking the position of the plume relative to the moving plate.一个柱相对于板块运动的轨迹。E说E.    provide an example of how mantle plumes manifest themselves on Earth’s surface把柱自身表现在地表。实质就是文章改写。而B。identify the evidence initially used to establish that the Pacific plate moves 说明最初用来建立太平洋板块移动的证据。一文章没讲明最初，二重心变成了介绍板块移动而不是plume相对板块移动了。

mayu912912

Q24不是直接细节题，句子作用题属于推断，应该选择在全文的作用而不是某段的作用，并且不应该明显反映在文中

siqi2future

http://huoshan.h.baike.com/article-13801.html   大家看看这篇中文就统统理解了，真心的。。

金暮蝉

这是一个很好的分析，摘自beatthegmat, from Stacey Koprince
http://www.beatthegmat.com/please-help-me-solve-this-t19739.html

I received a PM asking me to respond to this post with some suggestions for where in the passage to find the answers for each question.

I know you mentioned that you don't need a detailed outline, but I need to read it anyway to figure out what to tell you, so I'm going to type in my thoughts to myself as I read it, just to give you an idea of how I process the passage.

Earth - plates moving around, showing motions deeper down
like boiling water - hot stuff comes to the top and cooler stuff goes down
can cause volcanoes (usually at plate boundaries)
BUT there's another way to get volcanoes:
hotter rock = flows more easily
this hot rock collects deep down
when you get enough, it pushes up to make a bulge (volcano) even though it's not at a plate boundary
this kind can create chains or islands of volcanoes - eg Hawaii

Then I'd go back and label my first three lines "1 way" and the rest "the other way" (meaning the passage is split into two different ways to make a volcano)

Notice that I didn't use much of the official terminology - if I get a question, I'll go back and look at that, but on my first read-through, I'm mostly concerned with getting the basic idea.

Q1 Main idea
a couple of different ways to make volcanoes (can get this from my notes above). Answer D says almost exactly that.

Q2 inference - chain of volcanoes - I remember that's from towards the end of my notes, so I go scan the passage again. around 50.
"over a long period of time an active plume creates a chain of volcanoes"
So, if it takes place over a long period of time, those volcanoes must be different in age relative to each other. A is tempting because I remember seeing maps of volcano chains... but that's not in the passage. C is contradicted by the passage. D and E aren't discussed - I have no idea (so, therefore, I can't infer the info).

Q3 why does the author refer to Hawaii
From my notes - Hawaii is an example of the chain thing
A is fine until we get to "does not occur elsewhere" - this is one of the major two ways of making volcanoes
scanning down... E matches my original idea (which I developed before looking at the choices) - it's an example of how this alternate way works

Q4 specific detail - a "hot spot" is an example of what?
That's about the "hotter rock" which was also talked about in the second way (chains), so scanning the passage... there it is, between 40 and 45.
"the surface mark of an established plume is a hot spot - an isolated region of volcanoes and uplifted terrain located far from the edge of a surface plate."
So, not B. Not D - says nothing about being unique to Pacific. Need a little more info - back to the passage. So the "hot spot" is this "established plume" thing and a "plume" is the result of a reservoir of very hot rock from the mantle (around line 35).

A says the reservoir is "untapped" - but if it's coming up to the surface, then we can't call it "untapped." C says the rock is under enormous pressure - and I generally believe that, but I'm not finding a place in the passage where it specifically says that.

E calls it a plume, which the passage does say, and also says it's mantle rock, which is true according to the passage. And E says that this mantle rock comes from near the core and the passage does say that this stuff comes from the "base" of the mantle and describes it as having "proximity to Earth's core." So this one looks right! (This is all coming from around 25-35.)

sunny2l

siqi2future 发表于 2013-12-14 20:50
http://huoshan.h.baike.com/article-13801.html   大家看看这篇中文就统统理解了，真心的。。 ...

aaaaaaa真的感谢啊啊啊啊啊！！！真的豁然开朗了1！！！