Reading comp PrepTest 132 · Section 1 · Question 2

Passage

Questions 1-8  .        To study centuries-old earthquakes and the geologic  . faults that caused them, seismologists usually dig  . Remaining source text redacted.
Passage walkthrough
Passage Summary

Topic: Science


Paragraph 1

  • Paragraph note
    • Traditional approach to dating earthquakes (radiocarbon dating of carbon 14 isotopes in organic material near faults)
  • Views, minor Meta-Structures, and the author's attitude
    • Old approach:
      • Radiocarbon dating (of carbon 14 isotopes) of organic material trapped in sediments that show evidence of having shifted near fault lines (first through third sentence)
      • This can show the location and frequency of past earthquakes and the likelihood of future earthquakes (last sentence)

Paragraph 2

  • Paragraph note
    • New approach to dating earthquakes (lichenometry — measuring lichen growth along rocks)
  • Views, minor Meta-Structures, and the author's attitude
    • New approach:
      • Bull and Brandon developed lichenometry, which involves measuring lichen growth along rocks exposed by rockfalls following earthquakes (first through fourth sentences)
      • The number of rockfalls can show how strong the earthquake was and the location of rockfalls can help map the earthquake's epicenter (seventh and last sentences)
    • Example of lichen's slow and steady growth:
      • North American lichen, which grows 9.5 mm/year (fifth sentence)
    • Author's attitude: "provides direct evidence" (sixth sentence); "would imply" (seventh sentence); "can then be determined" (last sentence)

Paragraph 3

  • Paragraph note
    • Author on disadvantages of radiocarbon dating (not accurate in last 300 years, as the environment affects isotopes) and Bull/Brandon's requirements for lichenometry (minimize/factor disturbances like snow, shade, wind)
  • Views, minor Meta-Structures, and the author's attitude
    • Author's view:
      • Lichenometry has distinct advantages over radiocarbon dating, the latter of which is only accurate to within +/- 40 years and not of much use in the past 300 years (first through third sentences)
    • Bull and Brandon's view:
      • Lichenometry is accurate to within +/- 10 years and best in the past 500 years, but one needs to take into account the factors that can speed or slow lichen growth, like snow, wind, and shade (fifth through last sentences)
    • Cause-and-effect relationships:
      • Radiation on the Earth's upper atmosphere causes the amount of carbon 14 isotope to vary (second sentence)
      • Heavy radiation fluctuation in the last 300 years causes radiocarbon dating during this era to be useless (third sentence)
      • Snow avalanches and other disturbances can cause lichen growth to slow down (last sentence)
      • Shade and wind causes lichen growth to speed up (last sentence)
    • Author's attitude: "distinct advantages" (first sentence); "accurate only to within plus or minus 40 years" (second sentence); "fluctuated greatly" (third sentence); "of little value" (third sentence)

Main Point: Even though it requires careful site selection and calibration, lichenometry, a new technique for dating past earthquakes, has several advantages over the traditional radiocarbon dating technique.

Meta-Structure?

OldApproach/New Approach: This passage fits the Old Approach/New Approach Meta-Structure like a glove. In such a passage, the author will typically start by describing an old way of doing something or thinking about something. Often, this is referred to as the "traditional" approach or theory). The author will then describe a new, alternative way of doing or thinking about that same thing. Usually, the author prefers the new approach.

That's what happens here. The author introduces the "usual[]" technique in the first paragraph before shifting to the new technique in the second. When a passage utilizes this Old Approach/New Approach Meta-Structure, the author's opinion on the new approach is usually the main point. Here, the author feels that it has "distinct advantages" over the old technique, so we should ground our understanding of the main point in that view.

Last Thoughts?

Be careful with the end of this passage, starting in the fifth sentence of the last paragraph (beginning with "They note"). The author pivots here, stating that Bull and Brandon note some limitations on lichenometry — careful site selection and calibration. However, that doesn't undercut the author's claim that lichenometry has "distinct advantages" over radiocarbon dating, so we shouldn't feel as if this section is enough to make the author want to abandon the practice. That opening line of the third paragraph is still the clearest statement of the author's opinion.

Question prompt

The passage provides information Remaining source text redacted.
Why the credited answer is right

Credited answer: C

The notes below walk through why it fits the stem and how to eliminate the rest.

Question Type

Science

Strategy Overview

Remind ourselves of the main point of the passage, then head to the answers, focusing on those that line up with the main point and then using our notes/the passage to find the correct answer

Answer Anticipation

This is a variation of a Must Be True question. In this question, each answer choice is, Jeopardy-style, in the form of a question. The correct answer will feature a question that the passage answers. The four incorrect answers will present a question that the passage doesn't answer.These questions generally provide no indication as to the topic of the correct answer or where it'll show up in the passage. As such, we'll need to rely on our big-picture understanding of the passage to answer this question. We should start by reminding ourselves of the main point (either by reviewing what we said after reading the passage or by re-reading our answer to the main point question). From there, we can head to the answer choices. If we can't recall the answer to a question in a given answer choice, or if a possible answer isn’t related to the main point or reflected in our notes, we shouldn't comb through the passage, searching for an answer. Instead, we'll table that answer choice and move on to the next one. If we can recall the answer to a question — even vaguely — we'll use our notes/highlights/underlines to find the part of the passage that provides the answer. If we can point to the answer in the passage, we'll select that answer choice and move on to the next question.

Answer choices

  1. A
    How do scientists measure Remaining source text redacted.
    Why choice A is not credited

    (A) Is this answered by the main point, or do our notes suggest it is answered in the passage?

    Not really. Our note for the third paragraph says, in part, "Bull/Brandon's requirements for lichenometry (minimize/factor disturbances like snow, shade, wind)." That note suggests that the passage discusses "varying conditions that lichens may encounter" (like snow, shade, and wind), but it doesn't suggest that the passage explains how to factor in those conditions when measuring lichens. If the passage did explain that, our note would probably read, "Bull/Brandon's explain how to measure lichenometry" or something like that. So, we can safely eliminate — or at least table — (A) without checking the passage.

    If we had to review the passage to eliminate (A), we'd see that the third paragraph says that Bull and Brandon note that these varying conditions need to be considered, but the passage never goes into the details of how they do this.

  2. B
    How do scientists determine Remaining source text redacted.
    Why choice B is not credited

    (B) Is this answered by the main point, or do our notes suggest it is answered in the passage?

    Not really. Our note for the third paragraph says, in part, "Author on disadvantages of radiocarbon dating (not accurate in last 300 years, as the environment affects isotopes)." That note suggests that the radiation can vary in intensity, but it doesn't suggest that it explains how scientists determine how intense the radiation is. If the passage did explain that, our note would probably mention something about the scientists' methodology. So, we can safely eliminate — or at least table — (B) without checking the passage.

    If we had to review the passage to eliminate (B), we'd see that the author notes that the intensity has fluctuated for the past 300 years when discussing the shortcomings of radiocarbon dating (P3, S2-S3), but the author doesn't get into how scientists determine that intensity.

  3. C
    What are some of Remaining source text redacted.
    Why choice C matches the stem

    (C) Is this answered by the main point, or do our notes suggest it is answered in the passage?

    Yes! In fact, our notes practically answer this for us! Our note for the third paragraph reads, in part, "Bull/Brandon's requirements for lichenometry (minimize/factor disturbances like snow, shade, wind)." That suggests that snow, shade, or wind might encourage lichens to grow at a more rapid rate than usual. Still, we should check the passage to confirm that at least one of these factors speeds up lichen growth.

    Checking the third paragraph shows us that the author notes, "shade and wind ... promote faster lichen growth" (P3, S7). So, the passage answers this question. We can select (C) and advance straight to the following question.

  4. D
    What is the approximate Remaining source text redacted.
    Why choice D is not credited

    (D) Is this answered by the main point, or do our notes suggest it is answered in the passage?

    Nope. Neither the main point nor our notes suggest that the passage identifies the earliest earthquake that lichenometry has dated. Therefore, we can safely eliminate — or at least table — (D) without checking the passage.

    Besides, we wouldn't find an answer to this question if we re-read the entire passage. The passage says that lichenometry is best used for earthquakes that occurred within the last 500 years (P3, S5), but it's possible that lichenometry has dated some earthquakes that are older than that.

  5. E
    What are some applications Remaining source text redacted.
    Why choice E is not credited

    (E) Is this answered by the main point, or do our notes suggest it is answered in the passage?

    Nope. Neither the main point nor our notes suggest that radiocarbon dating can be used in other ways. So, we can safely eliminate — or at least table — (E) without checking the passage.

    Besides, we wouldn't find an answer to this question if we re-read the entire passage. While we may be able to infer some uses outside of dating earthquakes based on the description of the process in the first paragraph, we're looking for a question that information in the passage answers. And there's no indication of what other applications radiocarbon dating has, so we can eliminate this answer.

What this tests

Question analytics

Based on historical answer selection rates for this question.

Answer choice distribution

  1. A 14%
  2. B 3%
  3. C Credited 69%
  4. D 9%
  5. E 4%

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