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1、2022年考博英语-中国地质大学考前模拟强化练习题（附答案详解）1. 填空题Our initial fieldwork site（1） out to be completely unsuitable. Our team（2） over a week there before we recognized that we （3）never find the quality of fossils we were （4） for in that spot. 【答案】1. turned;2.worked;3.would;4. looking【解析】1.固定搭配。turn out to be被发现是，结果
2、是。而且此处应为过去式turned。2.语义题。第二空填不及物动词,因此worked符合句意。3.语法分析。第三空填would表示过去将来时。4.固定搭配。we were for是定语从句修饰the quality of fossils,那么第四空可填现在分词looking,构成look for “寻找”。2. 单选题1 For millions of years, Britain was part of the European continent. A high ridge of limestonenow famously exposed as the chalky cliffs of D
3、over-extended all the way to what is now France, allowing mammoths, hippopotami and eventually humans to pass freely back and forth. But about 450,000 years ago, this rocky road was cut off by a flood of unimaginable proportions. Now, a team of researchers has detailed evidence of how this torrent o
4、f destruction was unleashed. “Theyve managed to identify.how the ridge was breached,” says geologist Philip Gibbard of the University of Cambridge in the United Kingdom, who was not involved in the current study. “Im quite enthusiastic.”2 The idea that enormous floods quickly carved parts of the Eng
5、lish Channel was first proposed in 1985. At the time, geologist Alec Smith of Bedford College in London noticed large, interweaving scour marks on maps of the English Channel sea floor. He recognized that the patterns of erosion resembled those of the Channeled Scablands, a highly eroded landscape -
6、stark, barren and with little soilin eastern Washington state in the northwestern US. The landscape was formed by floods from glacial lakes that burst their icy dams between 15,000 and 18,000 years ago.3 Similar glaciers have existed in Europe. Some 450,000 years ago, a massive ice sheet spanned Sca
7、ndinavia, reaching down into northern Europe and much of what are today the British Isles. Hemmed in by the ice was a large glacial lake. No one knows exactly how big it was, but it may have been several hundred kilometers wide, and it likely filled the southern part of the North Sea. Because so muc
8、h water was stored on land as ice sheets, sea levels are thought to have been about 120 meters lower than today, exposing the bottom of what is now the English Channel.4 With the chalk ridge forming a dam to the south, and the Rhine and other rivers flowing into the glacial lake, the water would hav
9、e kept rising. Smith proposed that the lake would eventually have cascaded over the chalk cliffs. As evidence, he pointed to large, deep pits at the base of the former ridge “plunge pools” that were formed by the force of the waterfalls and later filled in with sediment. The scour marks on the chann
10、el bottom would have been carved by a vast flood rich in debris. Still unknown was what unleashed the deluge.5 The dramatic idea was then forgotten for many years. “I dont think many people believed it,” says Sanjeev Gupta, a geologist at Imperial College London.(Smith, who retired a few years after
11、 floating his idea, died in 2015.) “If smiths hypothesis now wins general acceptance, then the decades of delay will be oddly similar to the decades it took for the origin of the Channeled Scablands to be accepted. When the geologists JT Pardee and Harlen Bretz first argued that theScablands were th
12、e product of a short catastrophic flood of huge proportions, it took almost forty years to win over their fellow earth scientists.”6 Now Gupta and his colleagues have brought the idea of a cataclysmic breakup back into serious consideration. With data from British, Belgian and French research vessel
13、s, the team put together a clear picture of seven plunge pools on the channel floor (see map below), each nearly a kilometer wide and up to 140 meters deep even larger than Smith had estimated. “Its clear that the scale is really far greater than originally imagined,” Gibbard says, “The plunge pools
14、 were enormous.”7 The waterfalls pouring from the lake might have been 50 meters high or taller, Gupta says, although it is difficult to know. The relentless pounding of the cascades may have spun large blocks of stone inside the pools at the bottom, drilling into the bedrock. All this digging might
15、 have fatally weakened the ridge, eventually causing it to fail, Gupta and colleagues propose today in Nature Communications. “I think theyve worked out an intelligent account of how this may have happened,” says Kim Cohen, a geologist at Utrecht University in the Netherlands, who was not involved i
16、n the work.8 It is not yet possible to know how long it took the waterfalls to erode the chalk ridge, Gupta says. The only way to tell would be to collect samples by drilling into the sediments that later filled in the pools. But that is a tricky proposition, given the busy traffic of the shipping channel and its strong currents, its a dangerous area to do geological research in, says Gibbard, noting that just getting t
