Passage V
Heat flow is the escape of Earth's interior heat through the lithosphere (crust and upper mantle combined). For a given thickness, high heat flow indicates a rapid temperature increase with depth. Figure 1 is a cross-sectional view of oceanic and continental lithospheres.
Figure 2 shows heat flow, in watts per square meter (W/m2), for parts of the oceanic lithosphere and the average heat flows for both lithosphere types.
Figures adapted from Frank Press and Raymond Siever, Earth. ©1986 by W. H. Freeman and Co.
Figure 3 shows the average relationship between temperature and depth for both lithosphere types. The shaded areas are where lithosphere material would melt with and without water.
27. According to Figure 2, compared to other heat flow values, the heat flow measured from a back-arc basin is:
Your Answer is
Correct Answer is D
Explanation
Looking at figure 2, the heat flow at the back-arc basin is about 60 ×10-3 W/m2, almost the same as the average heat flow oceanic lithosphere, So choose D