The gravitational pull of the Earth varies on its surface depending on the thickness and density of the crust. The second-sharpest gravitational field variation in the United States, after a point in the Sierra Nevada mountains, occurs in the middle of this city. South of that line, gravity’s pull is stronger than north, suggesting some kind of division in the underlying crust.
In fact, the wishful weight watcher can find comfort that he or she actually weighs less (imperceptibly so) at Northgate than at Southcenter. Bedrock is thicker and a half-mile closer to the surface in the south than in the north.