Ever notice a pattern to New York City’s skyscraper location? (No tall buildings in Greenwich Village, but midtown and downtown are full of them.) It’s related to the city’s second-oldest bedrock:
Most of Manhattan is underlain by the Manhattan Schist, the bedrock that supports New York’s towering skyscrapers. …. Manhattan schist is found 18 feet below the surface in Times Square and 260 feet below in Greenwich Village. Where the schist dips down skyscrapers are much more difficult to construct because there is no bedrock to provide structural support. Greenwich Village remains a low-lying neighborhood, but skyscrapers dominate midtown and the financial district where schist lies close to the surface. Similarly, the supports for the George Washington Bridge are on Manhattan Schist.
In a city where seeing stars is rare, look down. If you’ve ever seen the sidewalks sparkle, you’ve spotted Manhattan Schist.