Global topography and plate tectonics. The colors represent different elevations of the Earth's solid surface. "Warm" colors (red and orange) represent high elevations; "cold" colors (blues) represent low elevations. The largest-scale plate boundaries--mid-ocean ridges and trenches--show up on the uninterpreted map above. The map below shows the plates and the plate boundaries. Red lines are mainly divergent boundaries, black lines are mainly convergent boundaries; and purple lines are transform boundaries. A=Alps; H=Himalayas; M=Mid-Atlantic Ridge; S=San Andreas fault. NJ lies in red box. Global topographic map from NOAA's National Geophysical Data Center website.