Composite cones are famous for their conical shapes with steep summits, sloping flanks, and broad base
How might the composition of eruptive materials have changed for the volcano to transition from something with a broad base to something with a smaller base and steeper slopes?
What will be an ideal response?
Answer: Early eruptive stages usually consist of lava flows that flow greater distances from the vent than later in the volcano's history. This process creates the broader base. As the volcano matures, lavas become more viscous, creating shorter, thicker flows that can create steeper slopes in the summit area. When pyroclastic materials are erupted, coarser materials fall closest to the crater and get finer farther away. This process helps to flatten the cone's flanks.
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A) Chinese B) North Africans C) Russians D) West Africans E) Portuguese
What is the only substance to have a higher heat capacity than liquid water?
A) Acetone B) Gasoline C) Ammonia D) Ice
How do geologists reconstruct an ancient environment from study of sedimentary rocks?
What will be an ideal response?