Sidney Horenstein, 82, Geologist Who Wrung Stories From Stone, Dies

Sidney Horenstein, an exuberant geologist whose popular books, guided tours and urban bias brought him fame as a champion of the rock that New York City is built upon (and with), died Wednesday in Manhattan. He was 82.

His wife, Marcia, said the cause was respiratory failure.

A staff geologist and coordinator of environmental public programs at the American Museum of Natural History and a lecturer at Hunter College in New York, Horenstein was an expert on the tectonic upheavals that shaped what was left of New York City’s natural landscape.

While other earth scientists might prefer prospecting in an unbuilt environment, Horenstein called New York “one of the great geologic meccas in the world” and a “geological smorgasbord.”

“The whole geology of the world is right here in New York City,” he told The New York Times in 1991. “Walk down Fifth Avenue and Sixth Avenue and you can reconstruct the history of the world from rocks that are used for building purposes.”

As a self-described “rockconteur,” he delighted in identifying the fossils that freckle the stone facades of skyscrapers and public restroom walls, and even where the stone had been quarried before it was transported to building sites in New York.

“Colonial coral fossils!” Horenstein would exclaim as he perused the paleontological record through a hand magnifier in the doorway of Saks Fifth Avenue, as oblivious shoppers brushed by.

No less fervor, on each rediscovery, would greet the Missouri brachiopods at the Brooklyn Municipal Building, or the white blob that turns out to be a fossilized 8-inch snail in the limestone (from Indiana) lobby of the Comcast Building in Rockefeller Center, or the Cretaceous clams in the Western Union Building in Lower Manhattan.

“Why do I love fossils?” he mused in 1978. “When you look at them, you’re seeing part of the evolution of life embedded on building stones.”

Horenstein would fascinate his audiences by explaining that rocks can serve as guideposts for anyone lost in Central Park, especially at night when light pollution obscures the constellations. (His tip: Thanks to the Taconic orogeny, or mountain-building period, the folds or curves in the rocks always plunge in a southerly direction.)

He explained why the park’s rocks are smooth enough to form natural slides (millenniums of glacial abrasion).

He would assure people that, urban legend to the contrary, the limestone lining the main concourse of Grand Central Terminal will not expose you to harmful excess radiation. (The average person is bombarded with 360 millirems a year from television sets, smoke detectors and cosmic rays; full-time workers at the terminal get about 120 from the walls.)

He comforted alarmists worried that the proliferation of skyscrapers downtown might cause Lower Manhattan to tip. (The stone excavated for their foundations actually weighs more than the hollow buildings themselves.)

Sidney Stanley Horenstein was born Nov. 11, 1936, on the Lower East Side of Manhattan. His father, Morris, was a barber; his mother, Mary (Schlanger) Horenstein, was a factory worker. He later lived in Queensbridge Houses, a public project in Long Island City, Queens.

As a boy, Horenstein bought Army surplus binoculars to explore the heavens, then shifted his focus to looking down instead of up. Falling stars were hard to find, but he could fill his pockets with the pebbles that fell onto the sidewalk from the marble contractors’ warehouses on Vernon Boulevard in Queens, not far from his home.

After graduating from Long Island City High School, he earned a bachelor’s degree in geology from Hunter College in 1958.

For four decades, he lectured and conducted field trips for the natural history museum, where he became environmental educator emeritus in 2004. He also led expeditions around the world for Smithsonian Journeys, under the auspices of the Smithsonian Institution.

His books include “Concrete Jungle: New York City and Our Last Best Hope for a Sustainable Future” (2007), written with Niles Eldredge, and “A Geologist Looks at Manhattan: A Guide to 100 Fascinating Sites” (2014).

Horenstein married Marcia Lichtenstein in 1967. In addition to her, he is survived by their daughters, Merrill McGarity and Jennifer Tejada, and four grandchildren.

The couple lived in the Inwood neighborhood of Upper Manhattan, which, because its terrain is roughly 445 million years old, imbued him with an usually long-term perspective.

Four years ago, while touring the excavation for the vast Manhattan West development project over the railroad yards near Pennsylvania Station, he was describing the folded gray Manhattan schist swirled with white pegmatite — a pattern formed when mud on the sea floor was molded as the plates that compose the earth’s crust violently collided.

“You don’t think we’re due for another collision do you?” Henry Caso, the Brookfield Office Properties vice president for constructing Manhattan West, asked warily.

“Not yet,” Horenstein reassured him. “Not for another 50 million years.”