Word: sedimenting
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...like neon and xenon, in the layer of Cretaceous clay deposited during roughly the same period that the dinosaurs became extinct. They were seeking to identify the nature of the object responsible for the impact. Because noble gases collect in carbon particles, the scientists isolated the carbon in Cretaceous sediment taken from Denmark, Spain and New Zealand. To their surprise, all three samples contained carbon that had been deposited at a rate 10,000 times as great as carbon in the layers immediately above and below them. It was bunched together in the fluffy patterns characteristic of common soot. Says...
...Earlier this year chemicals were found to be oozing into adjacent wetlands and into the Cochato--and leaching Lord knows where else, say the minority of townspeople who are upset. A water main that runs right under the site still supplies a thousand homes. Last spring the Cochato's sediment was found to include arsenic and naphthalene. Then last summer even the EPA seemed jolted: high concentrations of dioxin were discovered at Baird & McGuire...
Beyond the human density, the capital has a shaky geological base that makes it especially susceptible to earthquakes. Mexico City is built on the soft, moist sediment of an ancient lake bed; when jolted, says Caltech Earthquake Expert George W. Housner, it reacts "like a bowl of jelly." The city has, in fact, been sinking into its soft base at up to 10 in. annually. The drop has been uneven, creating a tilt in some foundations, thus placing those buildings at greater peril than others when the earth begins to rumble...
...away. That is because the shoreline is made of solid rock and thus shakes less violently. Mexico's capital, however, was built on an alluvial lake bed. As a result, the seismic waves, though diminished in intensity on their trip from the coast, were amplified in the city's sediment foundation. Many tall buildings in the densely populated metropolis may not have been built to rigid quake- resistant standards. Indeed, some turned out to be just the right height to vibrate or resonate sympathetically with the frequency of the seismic waves, thus shaking with greater vigor than other buildings...
...silver tray nestled in sediment. Bottles of vintage Bordeaux wine scattered on the ocean floor. A gaping hole where once a giant smokestack had stood. The ship's bridge, damaged by a falling boom. These and other poignant images of disaster, all in Picasso blue, were distributed in Washington last week at a news conference held by Marine Geologist Robert Ballard, leader of the expedition that early this month located and photographed the sunken liner Titanic. They were only a few of the 12,000 photos shot at the bottom of the Atlantic by the unmanned submersibles Argo and Angus...