提问！！NO2-1 sectionA 第二篇

燕燕小傻猫UID: 3204193

The energy contained in rock within the earth’s crust represents a nearly unlimited energy source, but until recently commercial retrieval has been limited to underground hot water and/or steam recovery systems. These systems have been developed in areas of recent volcanic activity, where high rates of heat flow cause visible eruption of water in the form of geysers and hot springs. In other areas, however, hot rock also exists near the surface but there is insufficient water present to produce eruptive phenomena. Thus a potential hot dry rock (HDR) reservoir exists whenever the amount of spontaneously produced geothermal fluid has been judged inadequate for existing commercial systems.
As a result of recent energy crisis, new concepts for creating HDR recovery systems—which involve drilling holes and connecting them to artificial reservoirs placed deep within the crust—are being developed. In all attempts to retrieve energy from HDR’s, artificial stimulation will be required to create either sufficient permeability or bounded flow paths to facilitate the removal of heat by circulation of a fluid over the surface of the rock.
The HDR resource base is generally defined to included crustal rock that is hotter than 150℃, is at depths less than ten kilometers, and can be drilled with presently available equipment. Although wells deeper than ten kilometers are technically feasible, prevailing economic factors will obviously determine the commercial feasibility of wells at such depths. Rock temperatures as low as 100℃ may be useful for space heating； however, for producing electricity, temperatures greater than 200℃ are desirable.
The geothermal gradient, which specifically determines the depth of drilling required to reach a desired temperature, is a major factor in the recoverability of geothermal resources. Temperature gradient maps generated from oil and gas well temperature-depth records kept by the American Association of Petroleum Geologists suggest that tappable high-temperature gradients are distributed all across the United States. (There are many areas, however, for which no temperature gradient records exist.)
Indications are that the HDR resource base is very large. If an average geothermal temperature gradient of 22℃ per kilometer of depth is used, a staggering 13,000,000 quadrillion B.T.U.’s of total energy are calculated to be contained in crustal rock to a ten-kilometer depth in the United States. If we conservatively estimate that only about 0.2 percent is recoverable, we find a total of all the coal remaining in the United States. The remaining problem is to balance the economics of deeper, hotter, more costly wells and shallower, cooler, less expensive wells against the value of the final product, electricity and/or heat.




According to the passage, if the average geothermal gradient in an area is 22℃ per kilometer of depth, which of the following can be reliably predicted?
I.
The temperature at the base of a 10-kilometer well will be sufficient for the production of electricity.
II.
Drilling of wells deeper than 10 kilometers will be economically feasible.
III.
Insufficient water is present to produce eruptive phenomena.
(A) I only
(B) II only
(C) I and II only
(D) II and III only（A）
(E)
I, II, and III

答案选A 我选的D 完全相反   请指点。。。这篇文章我只是勉强看懂关于一种能源的问题，很多细节并不是很懂，但是做题几乎全对（不限时，大约20分钟，几乎各种回头找文章中相似的句子），而且不会做标记。。。感觉回头找答案时很费时间。请问像我现在这种情况应当怎么纠正？还有在新G中，这样的长对话是不是不多啊？我看到这个题就哭了，长文章就算了，居然7个题。
天天开心  身体健康

水蜜桃tbUID: 3036767

一看22℃定位第五段。这一段讲HDR的resource base非常大，然后用22℃的情况进行对energy的量了估计和保守估计（说明energy很多）。最后一句说，remaining problem是平衡其他东西的花费与最终的产品、发出来的电。
看选项：
I根据这段内容，言下之意energy充足，发电完全可能（剩下唯一需要考虑的是投入成本），正确
II因为还有投入成本需要考虑，当然不是economically feasible，不对
III这一段没提到，直接排除

水蜜桃tbUID: 3036767

我最近也在做No题，感觉与新G差别还是很大。做No题很多时候定位到了就能做了，即使不知道什么意思；相比之下新G出题对逻辑的要求要高一些，如果没有看懂想清楚就很容易错。所以我对No题的训练价值还是有些疑惑的...
机考时代还是练习在头脑中做标记吧，杨鹏的六字箴言不是“边读边记边想”嘛~

燕燕小傻猫UID: 3204193

3# 水蜜桃tb 你阅读都用啥材料？我也在想这些题合不合适~

水蜜桃tbUID: 3036767

4# 燕燕小傻猫
我主要做了36套、OG和PP2

alteraUID: 2724954

NO题用来锻炼你读长文能力。

燕燕小傻猫UID: 3204193

6# altera 不知道是不是因为刚开始电脑阅读 看no题头晕。。。想吐~