A few dozen New Yorkers experienced their city at a new pace earlier this month. "Even the concrete we're standing on is changing," said artist Elizabeth Ellsworth, gesturing at the pockmarked floor of Studio-X in Lower Manhattan. "Everything in the city is a dynamic force."

Ellsworth and her collaborator, Jamie Kruse, were there to celebrate the launch of their new book. Geologic City: A Field Guide to the GeoArchitecture of New York (smudge studio, 2011) highlights 20 urban sites where humans interact with the region's complex geologic cycles. The water flowing from a New Yorker's faucet began as rain that trickled into an underground aquifer in the Catskill Mountains north of the city thousands of years ago. The metals used in skyscrapers and cars first were used to build our planet 4.5 billion years ago, and accumulated in rock formations thereafter. The calcium in 600,000 skeletons decomposing in Brooklyn's Green-Wood Cemetery began as igneous or limestone rock, thrust upward by the imperceptibly slow movement of Earth's crust; over millions of years, weathering released the rocks' calcium for uptake by plants, animals and humans.

The authors demonstrate that, in innumerable ways, the urban environment is intricately interwoven with processes that are far older than life itself.

Jessica Veenstra, an environmental scientist who bought the book, is excited to show it to her students at Flagler College in Saint Augustine, Fla. "In a lot of places you'll read about humans being separate from nature, not being treated as geologic actors," she says. "This book puts people into these cycles in a fun way."

The book's thought-provoking and whimsical images also belie a plea for environmental responsibility. "Humans need to understand deep time because we are capable of influencing the Earth for millions of years into the future," Ellsworth says. "We didn't evolve to contemplate it, but now we need to."

The human brain may not be hardwired to comprehend the billions of years of history that have shaped the modern environment, but there is hope, the authors wrote. As Geologic City demonstrates, the concepts that exceed human intelligence "can be experienced indirectly, through aesthetic works and acts of the imagination."

» View the Urban Geology Slide Show