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HOME > PAST ISSUE > May-June 2004 > Article Detail

MARGINALIA

A Tour of Geological Spacetime

Philip Morrison

L.A. Confidential

Upscale Rodeo Drive extends north from Wilshire Boulevard in Los Angeles, proffering a glossy collection of high shopping en route to exclusive Bel Air. Rather improbably, just three miles eastward along the boulevard lies the first earth-study destination, the tar pits at La Brea. Two dozen acres of parkland adjoin the thronged street. Instead of green grass, natural pools of hot, slow-simmering asphalt occupy the preserve. That engulfing blackness rises out of the earth from as much as 30 feet down, and it has done so for the past 40,000 years. A handsome little museum there provides the visitor with some helpful perspective, including a revealing, century-old photo of the site, in which a smoky and nearly unpeopled plain extends north to the hilly horizon. Only natural oil seeps give texture to the flatland where half the city now stands.

The excavations at La Brea, some still underway, have yielded the fossilized bones of thousands of incautious creatures caught in these sticky traps: Saber-tooth cats, vultures, white-footed mice and voles in variety have all emerged from the depths of this awesome fly paper. Only 17 human bones have ever been found, those of a young woman, perhaps an anciently abandoned victim of the tar. Visitors can glimpse such Pleistocene dramas at this small, compelling, earthly museum.

Not all of the destinations on the tour have such tiny scale: You need to be able to take in the long view of some things too. The North American continent is an example. Many people have wandered enough to visit east and west ocean coasts, but even seasoned travelers may not realize that about halfway between the equator and the North Pole, clear signs of continental drift are visible. As one steadily follows the setting sun, the Oregon coast appears with little notice, because the landscape is so new that the boundary between earth and sea is still being negotiated. You can even watch the process in style: Restaurants perched on steep cliffs allow you to sip wine as huge wind-driven waves contest with boulders below. On the Atlantic side, so abrupt an approach to salt water is uncommon. There the coast is old and worn. As a result, travelers to the sea are more likely to cross long foreshores, ample beaches and wide estuaries.




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