Word: occurance
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Dates: during 1990-1999
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...years ago, as the earth passed through the comet's orbit, it collided with the largest chunk, causing the Great Extinction. Perhaps only a year or two later, as the earth again entered the trail of cometary debris, it met a second, smaller chunk. Where did the second impact occur? This time no search is necessary. Shoemaker points to a well-known crater, 35 km (22 miles) across, that lies partly buried near Manson, Iowa. Its age, established by radioactive dating: 65 million years. / Shoemaker believes the new findings will help persuade more scientists to "get off the fence...
...some tastes, Brief Lives will lack the salt of irony, the sense that the narrator is deluding herself about the past or revealing more about herself than she imagines. Such moments of surprising revelation never occur; Fay is without guile. Her resentment at Julia's imperious way with other people seems perfectly straightforward: "Why did she, without doing anything for anyone, inspire such devotion, while humbler, clumsier people like myself seemed doomed to do without...
...main tools of the volcanologist include seismometers, which record the swarms of tiny earthquakes that occur as the magma rises. Chemical sensors, mounted on airplanes, can detect increases in sulfur-dioxide emissions, indicating that magma has reached the surface. In addition, the physical swelling of mountain slopes, well documented at Mount St. Helens, is a sign of explosive potential. Laser-based devices can pick up minute bulges that are about the width of a nickel and still invisible to the naked eye. In Japan researchers have set up video cameras to monitor the shape and color of fumes...
Done. If all goes well, if rejection does not occur or a major infection set in, the marrow will do the grail's work. It will give life to the older sister, who otherwise would have died of chronic myelogenous leukemia. Doctors rate the chance of success...
Ozone depletion and the greenhouse effect are human disasters. They happen to occur in the environment. But they are urgent because they directly threaten man. A sane environmentalism, the only kind of environmentalism that will win universal public support, begins by unashamedly declaring that nature is here to serve man. A sane environmentalism is entirely anthropocentric: it enjoins man to preserve nature, but on the grounds of self-preservation...