Because of its accuracy in outlining the Earths subsurface, the seismic-reflection method remains the most important tool in the search for petroleum reserves . In field practice, a subsurface is mapped by arranging a series of wave-train sources, such as small dynamite explosions, in a grid pattern. As each source is activated, it generates a wave train that moves downward at a speed determined uniquely by the rocks elastic characteristics. As rock interfaces are crossed, the elastic characteristics encountered generally change abruptly, which causes part of the energy to be reflected back to the surface, where it is recorded by seismic instruments. The seismic records must be processed to correct for positional differences between the source and the receiver, for unrelated wave trains, and for multiple reflections from the rock interfaces. Then the data acquired at each of the specific source locations are combined to generate a physical profile of the subsurface, which can eventually be used to select targets for drilling.
17. The passage is primarily concerned with
describing an important technique
discussing a new method
investigating a controversial procedure
announcing a significant discovery
promoting a novel application
18. According to the passage, in the seismic-reflection method all of the following have a significant effect on the signal detected by the seismic instruments EXCEPT the
presence of unrelated wave trains
placement of the seismic instruments
number of sources in the grid pattern
nature of the reflectivity of the rock interfaces
properties of rocks through which the wave train has traveled
19. It can be inferred from the passage that the seismic-reflection method would be likely to yield an inaccurate physical profile of the subsurface in which of the following circumstances?
If the speed at which the wave train moved downward changed
If the receiver were not positioned directly at the wave-train source
If the rock on one side of a rock interface had similar elastic characteristics to those of the rock on the other side
If the seismic records obtained for the different sources in a grid were highly similar to each other
If there were no petroleum deposits beneath the area defined by the grid of wave-train sources
20. Which of the following best describes the organization of the passage?
A method is criticized, and an alternative is suggested.
An illustration is examined, and some errors are exposed.
An assertion is made, and a procedure is outlined.
A series of examples is presented, and a conclusion is drawn.
A hypothesis is advanced, and supporting evidence is supplied.
Modern archaeological finds can still contribute much to the study of ancient literature. For example, forty years ago a survey of the early Greek dramatist Aeschylus plays would have started with The Suppliant Women. Many factors internal to the play, but perhaps most especially the prominence of the chorus , led scholars to consider it one of Aeschylus earlier works. The consensus was that here was a drama truly reflecting an early stage in the evolution of tragedy out of choral lyric. The play was dated as early as the 490s B.C., in any event , well before Aeschylus play The Persians of 472 B.C. Then, in 1952, a fragment of papyrus found at Oxyrhynchus was published stating the official circumstances and results of a dramatic contest. The fragment announced that Aeschylus won first prize with his Danaid tetralogy, of which The Suppliant Women is the opening play, and defeated Sophocles in the process. Sophocles did not compete in any dramatic contest before 468 B.C., when he won his first victory. Hence, except by special pleading , the Danaid tetralogy must be put after 468 B.C. In addition, a few letters in the fragment suggest the name Archedemides, archon in 463 B.C., thus perhaps tying the plays to that precise date, almost exactly halfway between Aeschylus Seven Against Thebes of 467 B.C. and his Oresteia.
The implication of the papyrus administered a severe shock to the vast majority of classical scholars, who had confidently asserted that not only the role of the chorus but also language, metrics, and characterization all pointed to an early date. The discovery has resulted in no less than a total reevaluation of every chronological criterion that has been applied to or derived from Aeschylus plays. The activity has been brisk, and a new creed has now spread. The prominence of the chorus in The Suppliant Women now is seen not as a sign of primitivism but as analogous to the massive choral songs of the Oresteia. Statistics have been formulated, or reformulated, to show that stylistically The Suppliant Women does actually occupy a position after The Persians and Seven Against Thebes, which now become the primitive plays, and before the Oresteia. While the new doctrine seems almost certainly correct, the one papyrus fragment raises the specter that another may be unearthed, showing, for instance, that it was a posthumous production of the Danaid tetralogy which bested Sophocles, and throwing the date once more into utter confusion. This is unlikely to happen, but it warns us that perhaps the most salutary feature of the papyrus scrap is its message of the extreme difficulty of classifying and categorizing rigidly the development of a creative artist.
21. The author of the passage focuses primarily on
discussing a series of modern archaeological finds and their impact on the study of Greek literature
recounting the effect of one archaeological find on modern ideas concerning a particular authors work
giving a definitive and coherent account of the chronology of a particular authors work
illustrating the many varieties of difficulties involved in establishing facts concerning ancient literature
determining the exact value of archaeological finds in relation to the history of ancient literature
22. With respect to the study of ancient literature, which of the following statements best expresses the authors main point concerning modern archaeological finds?
They can profoundly alter accepted views of ancient literary works, and can encourage flexibility in the way scholars look at the creative development of any artist.
They can be severely shocking and can have a revivifying effect on the study of ancient literature, which has recently suffered from a lack of interest on the part of scholars.
They can raise more questions than they answer and can be unreliable sources of information.
They generally confirm scholars ideas about ancient literary works and allow them to dispense with inferences drawn from the works internal structure.
They often undermine scholarly consensus in certain areas and create utter confusion concerning an authors work.
23. According to the passage, in the absence of definite knowledge concerning the dates of composition of ancient literary works, literary historians do which of the following when trying to establish the chronology of an authors work?
Make assumptions about a single works date of composition if such assumptions would not seriously affect interpretations of other works by the same author.
Draw inferences concerning the date of a works composition based on evidence internal to that work and on the authors other works.
Ignore the date of a works composition which is supplied by archaeological research when literary factors internal to the work contradict that date.
Refrain from speculation concerning a works date of composition unless archaeological finds produce information concerning it.
Estimate the date of a works composition without attempting to relate it to the authors development as an artist.
24. It can be inferred from the passage that which of the following plays or groups of plays is considered the latest in the date of its composition?
The Persians
The Danaid tetralogy
The Oresteia
Seven Against Thebes
The Suppliant Women
25. With which of the following statements regarding the chronological criteria mentioned in line 33-34 would the author be most likely to agree?
Such criteria, whether applied to or derived from the plays, should only be used to confirm already existing knowledge.
Such criteria, although derived from reliable external and internal evidence, should be changed continually to avoid rigidity in thinking.
Such criteria, based on statistical analysis, are inherently more reliable than those of forty years ago.
Such criteria, even when unsupported by external evidence, can resolve most questions.
Such criteria, based on often ambiguous internal evidence, can lead to erroneous reconstructions of the chronology of an authors work.
26. The authors attitude toward the activity mentioned in line 35 and its consequences can best be described as one of
amused tolerance
mocking envy
grave doubt
angry disapproval
unrestrained enthusiasm
27. The allusion to the hypothetical papyrus fragment in line 45-49 does which of the following?
Supports an argument concerning the date of The Suppliant Women.
Refutes the views of the majority of scholars concerning the Oxyrhynchus papyrus find.
Predicts the future results of archaeological research proposed in the passage.
Undermines the validity of the currently accepted chronology of Aeschylus works.
Qualifies the authors agreement with the new creed developed since the Oxyrhynchus papyrus find.
答案:17-27:ACCCBABCEAE
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