Page 344 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

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ridge (a), with more gentle dips of the water
Flow
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FIGURE
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b)
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lithosphere/asthenosphere boundary, compared bottom, Moho, and to slow spreading (b).
vs. Ridge Axis : i : (km) Ridge Axis a) The lithosphere cools (Mid- profiles like much is is heat enough tem- the contours, zone subduction forearc the while slab, in map The Zone Subduction great to descend 2.22, 7.23). of years. plate recent 10.14, (Figs.
Bathymetry From $ S read From ridge axes. Fast-spreading ridges show a wider area ridge steeper effect before meantime, the temperature the in low cold of the magma. may (Figs. of millions tens fairly of Mountains
Distance : Distance floor subsides as mid-ocean producing some melting. perturbs. region show a is ascending the linger Nevada
b) Fast- g thermal time In of broad a result Cascadia material earthquakes for areas
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(nd Bathymetry heat ocean the subduction zoné; ‘the the subducts, in within is brittely cold recognized and
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Heat From + Spreading - wom Spreading From Correlations of heat flow, a Fig. cube the from is ice a slab the Heat local reflects this shows Northwest consequence the roots like
10 & Distance _Fast - Slow Distance than cooler and Ridge: Subduction ice an the of When 10.19). a 10.14a Pacific depths, remaining time 10.16c).
Chapter _. semowee I SSS oO 10.17 faster the spreading rate. the elevation time. older Atlantic putting transferred perature decreasing (Fig. region, with high the Fig. the in A Through Lithosphere convergence. 10.15b,
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326 (2 Wi/fy) MOly BB} FIGURE of high through