lighter components.
B. Catalytic cracking is to convert all hydrocarbon fractions into lighter components. C. The cracking catalyst has the ability to change the heavy components’ conversion reactions.
D. The heavy components’ conversion reactions could not take place without the catalyst. 38、The word \ （D） A. components B. fuel C. oil D. fuel oil components 39、According to this passage, which of following sentences is true? （C） A. Heavy fuel oils are more valuable products obtained from crude oil. B. The pellet catalyst is more available than the powder catalyst.
C. With increasing cost of crude oil there is an increasing application of catalytic cracking. D. The cracking conversion takes place only in the presence of a catalyst. 40、The word \ （B） A. catalyst
B. The catalyst enhances the rate of cracking reactions and selectively to promote certain types of reactions. C. cracking reactions D. certain types of reactions
PASSAGE NINE
The migration of petroleum in general terms is better understood than its origin. It is useful to distinguish two phases of migration: primary migration within the source rock, secondary migration through the permeable carrier beds to the trap or to the surface. It is also important to make this distinction because the processes are probably different in important respects.
Primary migration takes place under the mechanical driving force of the compaction of the source rock under gravity, and may also be aided by molecular diffusion processes. It is not known that whether petroleum migrates as a separate phase (oil or gas in water) or as a solution in the water. There are mechanical difficulties in driving oil or gas droplets through the fine-grained rocks, and solution stage (which also has some chemical support) seems most likely. However, there is circumstantial evidence that petroleum acquires its essential
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character before primary migration is complete and secondary migration begins, because primary migration takes place in a more rigorous physical and chemical environment than secondary migration in sands, and both paths may be short. Nevertheless, some changes probably take place in the reservoir with time.
Primary migration, like petroleum generation, is poorly understood because it is a very slow process under constantly changing physical and chemical conditions that can not be realistically duplicated in the laboratory. Secondary migration does not suffer from this because it is a demonstrable process, when an oil or gas well is put on production, petroleum demonstrably moves through the reservoir rock to the well.
41、What does the passage mainly discuss? （C） A. Generation of petroleum B. Primary migration of petroleum C. The migration of petroleum D. Secondary migration
42、According to this passage, which of the following sentences is true? （A）
A. Primary migration takes place within the source rock, and secondary migration through the permeable carrier beds to the trap or to the surface.
B. Both primary and secondary migration take place within the source rock. C. Primary migration always takes place, and secondary migration rarely.
D. Primary and secondary migration take place through the permeable carrier beds to the trap or to the surface at the same time.
43、Which sentence could be implied from this passage? （A） A. The essential character of petroleum is acquired before secondary migration begins. B. The character of petroleum does not change through secondary migration. C. The character of petroleum does change a lot through secondary migration. D. The essential character of petroleum is acquired before primary migration begins. 44、What does the word \ （A） A. primary migration B. secondary migration C. migration D. petroleum
45、According to this passage, which of the following sentences is true? （C） A. Primary migration is a very quick process.
B. Primary migration can be realistically duplicated in the laboratory. C. Secondary migration is a demonstrable process.
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D. Secondary migration can be easily duplicated in the laboratory.
PASSAGE TEN
Horizontal wells are sorted by the radius of curvature in the well's build to horizontal. The wells are also discussed in terms of the build rate, which is inversely proportional to the radius of curvature. Both terms will be used when discussing the following well types.
Long radius (LR) wells are generally considered to be those that have build up sections between 1°/100'and 6°/100' or radius length between 5730' and 955'. Although Long radius holes were originally used on land, they are now used almost exclusively offshore. Long radius wells have several advantages. They are easier to drill and use conventional downhole hardware. Since well inclination can often be built and held using rotary equipment. Positive Displacement Motors (PDM) may not be required at all. In addition to using standard tubular and casing, the cost per day of service is typically lower than medium and short radius wells. Long Radius wells allow for drilling longer horizontal sections in excess of 5000', with an average of 3,500'.
Long radius wells have their drawbacks as well. The length of the radius necessitates a bigger rig with topdrive system, larger pumps and greater mud/cuttings management capability. Additionally, its longer openhole section increases risk for pipe sticking, kicks, and borehole damage, and may require extra protective casing strings.
46、What does the passage mainly discuss? （B） A. Horizontal wells B. Long radius horizontal wells C. Several advantages of long radius wells D. The drawbacks of long radius 47、The word \ （A） A. specially B. excluded C. clusive D. originally
48、With which of the statements is the author most likely to agree? （C） A. Long radius holes are merely used on land. B. Long radius holes are now used merely offshore.
C. Long radius holes are now used almost exclusively offshore. D. Long radius holes are now used almost exclusively on land.
49、The word \ （A） A. additional B. access C. process D. cess
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50、According to this passage, what topic may the author discuss in the folloing paragraphs? （C）
A. Conventional downhole hardware B. Vertical wells C. Other radius wells D. Pump
PASSAGE ELEVEN
When petroleum is first taken from the ground it is not very useful. After it has been treated in refineries it has many different uses. Most of the world's oil supply is used as some kind of fuel. The fuel may be used in different kinds of engines to give power, or to give heat in factories and in homes. Some of the world's oil is used for lubricating machinery, and some of it, in solid or semisolid form, called bitumen, is used in making roads. There are also many other uses for oil products.
For many years men used solid fuels, such as wood and coal, to provide power and heating. Oil is a liquid fuel. It is more useful than solid fuel for several purposes. When men discovered how to use liquid fuel it was possible to invent motor vehicles and airplanes. All fuels need air for burning. Liquid fuels easily evaporate to form vapor, which mixes well with the air and therefore burns quickly. Solid fuels cannot easily be dispersed in the air, so it is more difficult to burn them quick Liquid fuels burn up almost entirely, but solid fuels only burn part, leaving behind some ash. Also, liquid fuels are more easily stored and handled than solid fuels.
A liquid fuel which easily evaporates and turns into vapor is called 'volatile'. The most volatile oil fuel is gasoline, and this is used in most motor engines. (In Britain this fuel is called 'petrol'.) When oil was first being refined a hundred years ago, the internal combustion engine used in motor cars had not been invented so very little gasoline was produced. But great quantities of another oil fuel, kerosene, were produced, for burning in lamps. Gasoline is too inflammable for this purpose. 51、What may be the main topic of the passage? （B） A. Uses of gasoline B. Development of fuels C. Fuels D. Uses of petroleum 52、The word \ （A） A. oil B. bitumen C. lubrication D. machinery
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53、With which of the statements is the author most likely to agree? （C） A. Fuel is the only use of oil.
B. Making road is the biggest use of oil.
C. There are also many other uses for oil products besides fuels. D. Oil is the only liquid fuel.
54、The word \ （D） A. influential B. inflamed
C. favorable D. easily ignited and capable of burning rapidly 55、According to this passage, which of the following statements is likely to be true? （A） A. Kerosene is better for burning in lamps than gasoline. B. Kerosene is worse for burning in lamps than gasoline. C. Kerosene is as good as gasoline for burning in lamps. D. Kerosene is only for burning in lamps.
PASSAGE TWELVE
The greatest natural source of energy available to produce oil today traces its source back to the ancient seas in which the present-day rock formations were formed as sedimentary deposits, the same ancient seas in which present-day oil deposits originated as organic substances. This source of energy is the great quantity salt water existing in the porous channels of rock associated with present-day oil deposits. One must visualize the rock layer occurring over a very large area, with the oil reservoir being a relatively small structural feature into which oil migrated. Therefore, water occurs over a large area compared to the oil in the rock.
Although water is considered incompressible, the total compressed volume is quite large when such great quantities of total water volume are involved. Even the great volume of rock in which the water exists is influenced by water pressure. As oil produced, pressure declines at the point where oil is withdrawn from the reservoir. Water then moves in to replace the oil as is produced because of expansion of the minutely compressed water; a reservoir producing in this manner is termed a \world are producing by energy supplied by water drives.
The gas-oil ratio remains about the same in a water drive reservoir because pressure,
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