Identify the pair from the following list that is NOT correctly matched.
Show Hint
- Caldera – stratovolcano
- Pillow basalt – subaerial eruption
- Ropy lava – pahoehoe flow
- Amygdales – filled vesicles
The Correct Option is B
Solution and Explanation
Step 1: Understanding the question.
The question asks to identify the incorrectly matched pair. Each pair relates to volcanic features, and we need to identify which one is not accurate.
Step 2: Analyzing the options.
(A) Caldera – stratovolcano: This is correct. A caldera is typically associated with the collapse of a stratovolcano.
(B) Pillow basalt – subaerial eruption: This is incorrect. Pillow basalt forms in underwater eruptions, not subaerial (land-based) eruptions.
(C) Ropy lava – pahoehoe flow: This is correct. Pahoehoe lava flows are characterized by a smooth, ropy texture.
(D) Amygdales – filled vesicles: This is correct. Amygdales are cavities in volcanic rocks that are filled with secondary minerals.
Step 3: Conclusion.
The correct answer is (B) Pillow basalt – subaerial eruption because pillow basalts form during underwater eruptions.
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