Excavations Unlock New York City’s Dramatic Geologic Foundation

A decade of subterranean excavations on the Third Water Tunnel, the Second Avenue Subway, and the Long Island Rail Road’s East Side Access Project has provided geologists with unprecedented access to New York City’s physical structure.

1 minute read

February 22, 2014, 9:00 AM PST

By James Brasuell @CasualBrasuell


Sam Roberts provides a glimpse of the excitement experienced by geologists in recent years as they’ve explored the subterranean levels of New York City. Quoted int he article is Tony Hiss, the author of The Experience of Place, who describes what’s so exciting about New York’s foundation: “New York’s deepest and darkest secret, its oldest and most violent and previously only vaguely glimpsed history is finally coming to light — the schist that formed three-quarters of a billion years ago, when colliding continents compressed an ancient ocean; the even more elusive amphibolite, three times harder than concrete, that’s a slow-cooked remnant of islands as big as Japan off the New York shoreline.”

New York City's geology has also had a marked impact on the country’s most famous real estate market: “The application of that theory illustrates why skyscrapers historically sprouted downtown and in Midtown, but not in between. The bedrock — the formidable Manhattan Schist on which their concrete foundations rest — is closest to the surface in those two areas, though, nowadays, the technology exists to build almost anywhere.”

Monday, February 17, 2014 in New York Times

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