constituents.
It is a matter of expectation and experience that such a ―dry‖ gas, turned into a system formerly used to distribute manufactured or mixed gas, will immediately begin to absorb the water, light oils, tars, and naphthalene from pipe walls, with consequent dust formation and increase in leakage. Various means are adopted to counteract this influence.
Previous to January ,1927, the gas distributed was a 50/50 percent mixture of oil and natural gas. On Jan.25,1927, straight natural gas was introduced. By August, 1927, leakage had increased considerably, and steam was injected as a palliative measure. In November,1927, oil was introduced along with the steam, and in March, 1928,steam was discontinued and oil only injected. During the winter of 1927-1928 considerable dust was encountered, necessitating the installation of dust pots. Oil was continuously introduced throughout the remainder of 1928, but during the winter of1928-1929 a lesser, but nevertheless considerable , amount of dust was stirred up and the oil seemed t be detrimental in that it accelerated the plugging of the canvas filters in the dust pots.
106、On subsequent expansion the gas is very under saturated __________. （D） A.without respect to B. respect for C. respect to D. with respect to 107、The gas distributed was 50/50 percent mixture of oil gas and natural gas.50/50 means __________. （A）
A. go halves B. half and half C. half to half D. half size 108、Considerable amount of dust was stirred up. Dust was ________. （C） A. mixed through B. moved up C. found D. aroused
109、A ―dry‖ gas will immediately begin to absorb the water. The word ―absorb‖ means ________. （D）
A. join B. give out C. come in D. take in
110、When was the straight natural gas introduced? （D）
A. January, 1927 B. august , 1927 C. November, 1927 D. Jan.25, 1927
PASSAGE TWENTYTHREE
Characteristics of Oil
Nearly all naturally occurring petroleum deposits are made of an extremely large number of petroleum compounds. Petroleum compounds of these elements are called hydrocarbons, and each compound is made up of a different proportion of the two elements. Seldom are two crude oils found that are seemingly identical and certainly never are two crude oils made up of the same proportions of the various compounds. Within a single petroleum deposit, the mixture differs some from place to place and in many cases to an extreme degree.
The vast number of hydrocarbon compounds making up petroleum have been grouped chemically into series of compounds. Each series consists of those compounds similar in their molecular make-up and characteristics. Within a given series there exist compounds from
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extremely light, or chemically simple, to heavy, or chemically complex. As an analogy, the hydrocarbon may be compared to cattle; just as cattle are classified into different series. Just as there are a multitude of different size cattle within a breed, so within a hydrocarbon series there are a mulititude of compounds that differ because of the weight of the molecules of which they are made.
The most common and greatest number of hydrocarbon compounds making up a naturally occurring petroleum deposit are those of the paraffin series, which includes methane, ethane, propane, butane and others. Because of this, it has been the practice in the petroleum producing industry to analyze all petroleum samples according to their fractional composition based on the boiling properties of the various paraffin series constituents.
Whether a substance exists in a solid, liquid or gas phase will be determined by temperature and pressure conditions acting on the substance. It is well known that steam can be changed to water by lowering its temperature and water can be changed into ice by further lowering its temperature. Hydrocarbon compounds, either individually or in mixtures, will change their state or phase in the same way—by changing their temperature and pressure. The resulting change is called ―phase behavior‖. 111、Each petroleum compounds is made up of a different proportion of _____elements. （C） A. three B. four C. two D. many
112、 Within a hydrocarbon series there are a _____ of compounds. （A） A. great number B. small number C. great quantity D. small quantity 113、The most common and greatest number of hydrocarbon compounds making up a naturally occurring petroleum deposit are those of _____. （C）
A.methane series B. ethane series C. paraffin series D. butane series 114、The three states of the matter have some relationship with _______. （A） A. temperature and pressure B. temperature or pressure C. pressure D. temperature
115、 Hydrocarbon compounds, either changing individually or in mixture, will change their state ________ by changing their temperature and pressure. （A）
A. in the same way B. in the way C. on the way D. by the way
PASSAGE TWENTYFOUR
Petroleum
Crude oil and natural gas are the raw materials of the petroleum industry. It is the business of the industry to find them ,to retrieve them from the earth on —shore and off —shore, to manufacture useful products from them and to sell the products in the markets of the world.
The twentieth century might be described as pre—eminenly the age of petroleum. Although oil was first commercially exploited on any scale in the late nineteenth century , the
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twentieth century has seen the development of oil into ―the biggest business‖, the growth of large—scale international petrochemical industry, and the rise of natural gas as a prime source of energy.
Customer demand has propelled this growth. The exceptional versatility of crude oil as a base material for the manufacture of a very wide range of products, the convenience and cleanliness in use of oil and gas, their ease of transportation and storage, their relative cheapness, their particular efficiency for such special purposes as providing energy for transportation ,raw material for lubricants, and feedstock for the petrochemical industry…these factors have powerfully stimulated growth and given petroleum major importance in the economies of producer and consumer countries alike.
Oil production figures speak for themselves:
Million barrels per day
1900 0.4 1940 6.0 1950 11.0 1960 22.0 1970 48.0 1980 62.9
This enormous expansion has meant that producer countries have become heavily reliant on oil for national revenue and foreign exchange. In most consumer countries, oil has also dominated national economies, as a major component. Today, virtually everyone in society is affected by the availability and price of oil and gas: directly in terms of domestic use and family transportation; indirectly in relation to jobs and to many other aspects of national economies, whether they are buoyant or in difficulty.
116、It is the business of the industry to ______oil and gas from the earth onshore and offshore. （A）
A. recover B. find C. save D. dig
117、Oil was first commercially _______on any scale in the late nineteenth century . （C） A.logged B. drilled C. developed D. explored 118、Oil production figures ________themselves. （A） A. express B. say something for C. give evidence on behalf of D. talk on behalf of
119、In ―Million barrels per day ‖, ―per‖ means ________. （B） A. through B. for each C. according D. for
120、In most countries, almost every one in society is effected by the availability and price of oil and gas: directly _______domestic use and family transportation. （A） A. in respect of B. in the conditions of
C. at the price of D. in direction of
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PASSAGE TWENTYFIVE
Reading comprehension Folds
Folds are manifest as different types according to morphology, origin, and type of internal deformation. General fold terminology is descriptive and relates to elements of individual features applicable to all types of folds.
An anticline is a fold with upward convexity. A syncline is a concave upward.
The hinge point occurs at the locus of maximum curvature of a fold. The hinge point is applicable equally to anticlines and synclines. Hinge points connected on any particular bedding surface are joined along a hinge line.
The locus of all hinge lines of a fold is the hinge surface of the fold.
An inflection point occurs where bed curvature in one direction changes to bed curvature in the opposite direction. Inflection occurs where concavity changes to convexity.
The limbs, or flanks of folds, are those portions adjacent to the inflection lines of folds. They converge upon the inflection line synclines and diverge from it in anticlines.
A fold is symmetrical when its shape and mirror image are identical or when the fold is bilaterally symmetrical about the hinge surface. Symmetrical folds are usually represented by a vertical hinge surface.
A fold that is not bilaterally symmetrical about the hinge surface is asymmetrical. Its hinge surface is characteristic of a recumbent fold. The beds in the bottom limb of a recumbent fold are upside down.
121. What dose the word ―manifest‖ mean in this passage? (D ) A. made B. many C. manifold D. apparent
122. Which of the following sentences is true? (B ) A. An anticline is a fold with upward concave B. A syncline is a concave upward.
C. An anticline is a fold with downward convexity D. A syncline is a concave downward.
123. Where dose an inflection occur? (A ) A. Where concavity changes to convexity. B. In a syncline. C. In an anticline.
D. Anywhere in the strata.
124. A fold that is not bilaterally symmetrical about the hinge surface is called? ( B ) A. symmetrical B. asymmetrical
C. the limbs D. an inflection point
125. What is the passage mainly about? (C ) A. hinge surface B. anticline C. fold terminology D. syncline
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PASSAGE TWENTYSIX
Logging and Formation Evaluation
The gamma- ray log is an example of a nuclear log. It is often run in combination with a neutron and density log which serves to estimate the porosity of a formation. The neutron sonde contains a radio- active source that emits fast neutrons which penetrate the formation and are there slowed down by collisions with atomic nuclei. Such nuclear logs can also be run in cased holes. The cement and casing steel will attenuate the recorded signals and for quantitative evaluation the logs may still be useful, but less accurate. They will serve mostly for correlation, however. An ―acoustic‖ or ―sonic‖ log is another type of porosity log which in frequently run.
In order to obtain the water saturation, the resistivity log is necessary. If the salinity of the formation water is known, the rock’s water saturation can be calculated.
From the density log and sonic log a rock’s acoustic impendence can be calculated. In a seismic survey, seismic reflections occur when adjacent earth layers differ enough in acoustic impedance. Hence logging can be used for identifying the reflection points in a seismogram, but also for quantitative calibration. By studying the influence of the presence of either gas, oil or water on the logged acoustic impedance, predictions can be made laterall on the seismic record on the extension of hydrocarbon- bearing interval.
In the past, all wire line logs were recorded as curves on films. To meet requirements such as high- density storage of large quantities of data and easy input into modern computer and data handling systems and to facilitate fast transmission of data via telecommunication networks, well logs are now recorded on digital tapes.
126. Which of the following words can represent the word ―collision‖ in the first paragraph?(A )
A. encounter B. running C. revolution D. motion
127. According to the passage, another frequently run porosity log besides nuclear log is? (B ) A. neutron log B. acoustic log C. mud log D. density log
128. Which is necessary before the rock’s water saturation can be calculated? (D ) A. content of the formation water B. mud in the formation water C. density of the formation water D. salinity of the formation water
129. What should we study before we can predict the lateral seismic record on the extension of hydrocarbon-bearing intervals? (C ) A. the logged acoustic impedance B. the presence of gas, oil and water
C. how gas, oil and water affect the logged acoustic impedance D. the principles of gas, oil and water migration
130. What are well logs recorded on nowadays? (C ) A. film B. paper C. digital tapes D. wood
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