Examkin

Question

Difficulty: MediumEvaluating the Impact of New Evidence

### Venusian Resurfacing

The surface of Venus has relatively few impact craters, indicating that the planet was resurfaced relatively recently. Scientists debate the mechanism and timing of this resurfacing.

Hypothesis 1 (Catastrophic Resurfacing)
Venus underwent a sudden, planet-wide resurfacing event approximately 500500 million years ago. During this brief period, massive volcanic eruptions covered the entire planet in lava, erasing all previous craters. Since that event, Venus has been volcanically quiet, and no significant volcanic activity has occurred.

Hypothesis 2 (Gradual Resurfacing)
Venus's surface is renewed gradually over time by steady, ongoing volcanic activity. Localized volcanic eruptions occur continuously in different regions rather than in a single global event. This process slowly and continuously resurfaces the planet over hundreds of millions of years.

New Evidence
Astronomers monitoring Venus detect active volcanic plumes releasing sulfur dioxide gas into the atmosphere and observe localized hot spots on the surface that appear and disappear over several months.

Based on the new evidence of active volcanic plumes and hot spots, which of the following statements best describes the impact of this evidence on the two hypotheses?

  1. A
    It supports Hypothesis 1 and weakens Hypothesis 2, because active plumes show that resurfacing is confined to a single geological epoch.
  2. It supports Hypothesis 2 and weakens Hypothesis 1, because active volcanic plumes indicate that Venus is currently volcanically active rather than quiet.Answer
  3. C
    It weakens both Hypothesis 1 and Hypothesis 2, because active plumes suggest that atmospheric changes, not volcanic activity, resurface the planet.
  4. D
    It supports both Hypothesis 1 and Hypothesis 2, because any volcanic activity confirms that the planet was completely resurfaced 500500 million years ago.

Answer

The correct answer is the option stating that the evidence supports Hypothesis 2 and weakens Hypothesis 1, because active volcanic plumes indicate that Venus is currently volcanically active rather than quiet.
The correct answer is the option stating that the evidence supports Hypothesis 2 and weakens Hypothesis 1. Hypothesis 1 states that Venus has been volcanically quiet since a catastrophic event 500500 million years ago, so the discovery of active plumes and hot spots directly contradicts and weakens this claim. Hypothesis 2 states that resurfacing is gradual and ongoing due to steady, continuous volcanic activity, so active volcanism directly supports this claim.

Step-by-Step Solution

1
Identify the core claim of Hypothesis 1 regarding recent volcanic activity.
Hypothesis 1 claims that Venus has been volcanically quiet and inactive for the last 500500 million years.
To evaluate if the new evidence supports or weakens this hypothesis, we must establish its prediction about current volcanic activity.
2
Identify the core claim of Hypothesis 2 regarding current volcanic activity.
Hypothesis 2 claims that Venus experiences ongoing, steady, and localized volcanic activity.
To evaluate if the new evidence supports or weakens this hypothesis, we must establish its prediction about current volcanic activity.
3
Analyze the new evidence and compare it to the claims of both hypotheses.
The detection of active volcanic plumes and changing hot spots indicates that Venus is currently volcanically active. This contradicts Hypothesis 1's claim of quiescence (weakening it) and supports Hypothesis 2's claim of ongoing activity (supporting it).
By comparing the observed current activity with the predictions, we can determine the logical impact of the new evidence.

Key Concept

Evaluating the impact of new evidence on conflicting scientific hypotheses
Estimated Time:1m 30s
Rate this question

Topics

Evaluating the Impact of New Evidence

More questions from this topic