A sensational new scientific discovery in the ocean near Australia may explain the most massive extinction of living things in Earth’s history. For years, scholars have been frustrated in trying to analyze why 90 to 95 percent of sea life and 75 percent of and life vanished about 250 million years ago. The extinctions were so enormous that they are called The Great Dying. To date, some authorities on ancient life thought that a volcanic eruption or a sudden change in the environment affected all life on Earth. Other specialists have doubted these theories, maintaining that it was not plausible that a solo volcano could bring about such chaos. From the outset, critics believed these claims were exaggerated.
By contrast, there is wide acceptance of the idea that a meteor (流星)which hit Mexico’s Yucatan peninsula 65 million years ago was the primary cause of the dinosaurs’ extinction. Nevertheless, until now they had no evidence of an intense meteor impact 185 mill on years earlier. Now they do.
American geologists have been examining rock samples from a deep sea crater (火山口)near the northwest coast of Australia. The samples were initially collected and preserved by petroleum technicians seeking oil. Now the geologists and their colleagues believe that the precise splits in the rock’s structure show a typical pattern for meteors. There is a clear distinction from volcanic patterns. In fact, a spokesperson went so far as to say that these rocks completely revise the way scientists perceive the mass extinctions from the ancient era. Academics say that the meteor’s crater s the size of Mount Qomolangma, the highest mountain on Earth! Literally, the meteor made a mark on Earth as it drowned in the sea. The Earth could not absorb such a harsh blow without sustaining global devastation. Things must have come to a standstill. Evidently, the blow was fatal for many forms of life.
Bear in mind that all this was long before mammals---including humans--emerged in Earth’s history. Still, we would be wise to pay attention to the damage a meteor can cause. Fortunately, meteor strikes on Earth are few and far between.
【小题1】The word “plausible” (paragraph 1) is closest in meaning to “______”.| A．available | B．incredible |
| C．reasonable | D．ridiculous |
| A．Because they were very resistant | B．Because there weren’t any then |
| C．Because they lived in isolated areas | D．Because they hid themselves in the caves |
| A．Scholars agreed that a single volcano caused The Great Dying |
| B．75 percent of land life continued 250 million years ago |
| C．Volcanic rocks and meteors have different patterns |
| D．When the meteor hit land Mount Qomolangma sprang up. |
| A．The Dinosaurs’ End | B．Crater on Qomolangma |
| C．Contradictory Claims | D．A Meteor’s Impact |
