My understanding is that Long Island (Brooklyn and Queens are the westernmost top of Long Island, for those not familiar with the local geography) is the remnan

My understanding is that Long Island (Brooklyn and Queens are the westernmost top of Long Island, for those not familiar with the local geography) is the remnants of the mountaintops of the Hudson Valley, that got scraped off during the last Ice Age and pushed into the ocean by the glaciers. Which means the whole island is essentially built on landfill.