彭蒙惠英语：Newsworthy Clips（在线收听）

Newsworthy Clips

1

Sinking Islands Pointed to Danger of Earthquake

By Glennda Chui / © 2004, as first appeared

in San Jose Mercury News, Knight Ridder

Newspapers. Distributed by Tribune Media

Services International.

For decades, scientists say, tiny islands off the west coast of Sumatra had been sinking-an ominous sign that strain was building toward a great earthquake, which would set off tidal waves that could kill thousands of people.

That’s exactly what happened on December 26, 2004. Giant quakes suddenly pushed up the ocean bottom, raising a bulge of water on the surface that rippled out in all directions. The resulting waves, or tsunamis, would have been about a foot tall as they raced across the ocean at 500 to 600 mph. But when they hit shallower water near shore, they piled up into walls of water up to 30 feet high, depending on the shape of the coastline and the contours of the

ocean bottom.

The first tsunamis might have looked like angry waves or rapidly rising tides. As the first one receded, exposing the ocean bottom, people would have been tempted to go gather up any fish left behind, only to be trapped by a second wave as powerful as the first, arriving 10 minutes to an hour later. Four or five tsunami waves may hit in succession, traveling thousands of miles to menace distant shores.

The 9.0-magnitude earthquake about 125 miles off the west coast of Sumatra occurred in an area that is marked by a deep underwater trench.

Based on clues found among the area’s coral reefs and along its beaches, scientists know that this is the fourth giant earthquake to strike the same fault zone, known as the Sumatran subduction zone, since 1797. Here, one giant plate of the Earth’s crust is diving beneath another, pushing the ocean bottom underneath Sumatra at a rate of about two inches per year. The plates can become stuck, accumulate strain for decades or centuries, and then suddenly spring loose in an earthquake.

Vocabulary Focus

ominous (adj) [5CminEs] suggesting something unpleasant is likely to happen; threatening

contour (n) [5kCntuE] the shape of a mass of land or other object, especially its surface or the shape formed by its outer edge

menace (v) [5menEs] to cause harm to someone or something, or be likely to cause harm

Specialized Terms

mph (abbreviation) 每小时里程数 miles per hour: the number of miles a vehicle travels in one hour

trench (n) 地沟 a narrow channel dug deep into the ground

fault zone (n phr) 断层带 an area consisting of numerous cracks in the Earth’s surface where rock has divided into two parts that move against each other

subduction (n) 潜没 a process in which an edge of one of the plates of the Earth’s crust is forced below the edge of another