Passage: 'In planetary volcanology, shield volcanoes like Olympus Mons on Mars attain enormous dimensions—exceeding 21 kilometers in height and 600 ki

Question

Passage: 'In planetary volcanology, shield volcanoes like Olympus Mons on Mars attain enormous dimensions—exceeding 21 kilometers in height and 600 kilometers in diameter—primarily because Mars lacks active plate tectonics. On Earth, moving tectonic plates continuously shift the crust over stationary mantle hotspots, producing chains of smaller volcanic islands (such as the Hawaiian archipelago). On Mars, stationary crust remained positioned directly above an upwelling mantle plume for hundreds of millions of years, allowing successive basaltic lava flows to accumulate in a single monolithic structure.'

According to the passage, why are Martian shield volcanoes so much larger than their terrestrial counterparts?

Accepted Answer

The absence of mobile tectonic plates kept the Martian crust fixed over a stationary mantle plume, causing continuous localized lava accumulation.

Answer

Martian basaltic magma contains higher concentrations of trapped water vapor, causing violent explosive caldera expansion.

Answer

Extreme solar wind stripped away surrounding sediments, exposing the volcanic core.

Answer

Martian gravity is twice as strong as Earth's gravity, compressing lava flows into high peaks.

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