Question

Pahoehoe is:

a. the point on subducting crust above which a volcano forms
b. another name for the aluminosilicate triple point
c. the lowest temp at which a solid solution mixture will melt.
d. the lowest temp at which a mixture with no solid solution
e. NOA

Answer 1

Pahoehoe is a type of smooth and ropy lava, typically found in volcanic regions like Hawaii and related to hotspot-driven volcanic activity, not to the melting points or formation points of volcanoes above subducting crust.

Step-by-step explanation:

The term pahoehoe refers to a type of lava characterized by a smooth, billowy, or ropy surface. It's formed under certain temperature and viscosity conditions as lava flows and cools. Pahoehoe is commonly associated with the volcanic activity of hot spots, such as the one beneath the Hawaiian Islands. Contrary to the choices given in the question, pahoehoe is not related to the point of volcano formation above subducting crust or specific melting points of mineral mixtures.

In geographic and geological contexts, understanding volcanic features like pahoehoe helps in studying the nature of individual volcanoes and the mechanisms behind mantle plumes and hotspot-driven volcanic activity. When basaltic lava flows relatively slowly and has a low viscosity due to high temperatures, it can form pahoehoe lava flows, which are notably different from more viscous, rough-textured 'aa' lava flows.