Unit 8 Part I
UNIT 8
Part I
Text: Field Geophysics
Grammar : Degrees of Comparison
Ex.1. Translate the following sentences into Russian.
1. The geologic age of a reservoir is older than 10million years.
2. The crust 0-25 miles down is the earth’s thin topmost layer, thinnest under the ocean and
thickest under the continents.
3. The history of petroleum is almost as long as the history of civilization itself.
4. The slower magma cools, the larger crystals grow.
5. In general the greater the intensity of the earthquake shock, the longer it lasts.
6. The older the rocks, the less their fossils resemble living forms; the younger the rocks, the
more their fossils resemble living forms.
7. The origin of the earth is the most important and the most difficult question of natural
science.
8. The quantity of water in the oceans is almost fifteen times as great as that of all the rocks
of the continents and islands above sea level.
9. The lower limit of wave action varies, and may be as much as 600 feet.
10. The more complex the geology of the area being studied, the more computing power is
required to process the massive quantity of data.
11. Relative magnetic measurements are much simpler and the instruments are much lighter.
12. The greater the tectonic forces, the higher the pressure and temperature affecting the rock
mass and the greater the amount of resulting structural deformation and metamorphism.
13. The greater and the more sudden is the change of temperature, the greater is the breaking
of rocks.
14. As soon as rock is exposed to the weather, it gradually starts to break down under the
action of wind and rain, frost and sun.
15. The heavier and more viscous is the oil, the slower is the rate of flow.
16. Speculation on the origin of oil was initiated as early as in the 1860-s.
17. The process of soil formation is as old as most of the rocks now found in the crust of the
earth.
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Ex.2. Combine two sentences into one using the Infinitive as an adverbial modifier of
result.
e.g. The problem is too complicated. It cannot be described in a few words.
The problem is too complicated to be described in a few words.
1. The error is too common. It cannot be neglected.
2. The data are accurate enough. It can be relied upon.
3. Seismic survey is reliable enough. It can provide a true picture of the underground.
4. The grains of the mineral are too small. They cannot be seen with a naked eye.
5. The movements of the earth crust are too slow. They are not noticeable.
Ex.3. State the part of speech of the underlined words. Translate the sentences.
1. Movement of the atmosphere in the form of strong wind is an important agency, and
is, in addition, a leading means of erosion.
2. The mean density of the earth 5.5 means that a cubic foot of average earth substance
weighs about 5.5 times as much as a cubic foot of water.
3. Most minerals can be quickly identified by means of the petrographic microscope.
4. We can read records in the rocks from which we reconstruct the evolution of the
earth.
5. A seismograph records earthquake shocks.
6. Changes in velocity of the transporting agent commonly cause stratification. Another
cause of stratification is a change in the kind of material that is being deposited.
7. Another, though much less important, cause of earthquake is volcanic activity. A
violent eruption often causes the earth to quake.
8. The chemical weathering effects of rain are seen in its solvent action on some rocks,
mainly limestones.
9. Variations in the temperature of the atmosphere effect great changes in rocks.
Temperature changes are usually of more effect in the case of igneous rocks than in
that of sedimentary rocks.
10. The horizontal sands were found to wave considerably in several places.
11. Waves and currents sometimes pile up sand along the coastline.
12. There are methods used to find indirect evidence of the presence of hydrocarbons.
13. Potential recoverable volumes estimated for the find are 710 million bbl of oil.
14. During earthquakes compression of water-saturated sands may force the underground
water to rise along fractures.
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15. Under the force of high pressure oil moves upward.
WORDS TO THE TEXT “FIELD GEOPHYSICS”
чувствительный (о приборе)
1. sensitive adj.
Sensitive instruments are able to measure very
small changes.
1.точка, отметка; 2. пункт, вопрос, дело
2. point n.
1. a freezing point; a northern point on the map;
a point of view
2. a turning point in a career, the point of the
discussion
point (at;to) v.
указывать на (что-либо), свидетельствовать о
All signs point to a significant accumulation of
oil in this region.
3. oil – (gas -) bearing adj.
нефте(газо)носный
an oil-bearing horizon; a gas-bearing layer.
4. enable v.
делать возможным, позволять
The new method enabled the geologists to get a
true picture of the subsurface.
5. slight adj.
небольшой, незначительный
a slight mistake, a slight difference
6. suggest v.
1. предлагать, советовать;
2. предполагать, наводить на мысль
1. Gubkin suggested new methods of training
petroleum geologists.
2. The subsurface information suggests a strong
possibility of hydrocarbons at the depth.
7. guideline n.
основные направления, нормативы
The company has issued new guidelines for
working in harsh environment.
8. precise adj.
точный, определенный
a precise meaning, a precise measurement
9. event n.
явление, событие
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a historical event; a geologic event; a seismic
event
10. reflect
v.
отражать
Silver paper behind a radiator helps to reflect
heat.
11. refract v.
преломлять
Light is refracted by a prism.
12. array n. (seismic)
группа (источников), комплект
geophone array
13. inclination n.
наклон; отклонение
There is a slight inclination in the trajectory of
the well.
14. attenuation n.
затухание, ослабление
The receiver recorded the attenuation of the
seismic signal.
Ex.4. Read the text “Field Geophysics”. Find international words in the text and give their
Russian equivalents.
FIELD GEOPHYSICS
Geophysics is the study of the physics of the earth, its oceans, and its atmosphere.
Petroleum geologists are most interested in the earth’s magnetism, gravity, and especially
seismic vibrations, or vibrations of the earth. Sensitive instruments can measure variations in one
of these physical qualities that may be related to conditions under the surface. These conditions,
in turn, may point to probable oil-or gas-bearing formations. Searching for oil and gas through
geophysical means does not guarantee a successful find, but the combination of geophysical
information and geological know-how reduces the chances of drilling a dry hole.
Geologists searching for petroleum have made good use of the fact that the earth has a
strong magnetic field. Applying the principle that like rocks have like magnetic fields enables the
geologists to compare slight differences in the magnetism generated by the minerals in the rocks.
These differences suggest the locations of different formations and a fairly good picture of its
configuration.
Rocks of differing composition have different electrical properties. Geologists record and
measure the naturally occurring flow of electricity between rocks or across salt water, for
example, and then analyze and interpret the information to reveal subsurface structures and oilbearing rocks that are most likely to be found.
Geophysicists also make use of slight variations in the earth’s gravitational field caused
by the varying weight of rocks. Gravity maps and models help the geologists examine large areas
of development and provide guidelines for planning a seismic exploration program, but it is not
accurate enough to be fully relied on.
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Seismic survey unlike the methods mentioned above gives more precise details on the
underground formations.
Seismic measurements involve first the generation of a seismic event, a mini earthquake
that is transmitted downward from the surface. A seismic wave migrates into the ground and is
reflected and/or refracted up from each interface between layers of different hardness and
density. The deeper the layer is in the earth, the longer it takes for a signal reflected from that
layer to arrive at the surface and be detected by an array of receivers.
Massive amounts of data points are thus collected. They are then visualized and analyzed.
The interpretation of the information obtained allows determining the depth and inclination
angles of the subsurface reflectors. The lithological characteristics can be determined from the
reflection amplitudes and attenuation characteristics contained in the reflected signals.
The evolution of seismic measurements has come a long way from an exploration tool.
Today the measurements under discussion provide information on the structural features which
are associated with hydrocarbon accumulations as well as the presence of gas and the movement
of fluids in the reservoir.
Ex.5. Match synonyms in A and B.
A
B
instrument
property
quality
discovery
to relate
tool
find
to help
to reveal
to connect
to reduce
to bring about
enough
to discover
to cause
accurate
inclination
pool
accumulation
sufficiently
to enable
dip
precise
to decrease
Ex.6. Match antonyms in A and B.
A
B
to reduce
stable
strong
different
like (adj)
inaccurate
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difference
absence
artificially
weak
varying
to raise
downward
naturally
presence
likeliness
precise
to prevent
to enable
upward
Ex.7. Make word combinations from the given verbs and nouns. Form as many variants as
possible.
to measure
find
to record
vibrations
to reduce
wave
to apply
cost
to reveal
survey
to interpret
configuration
to cause
structure
to provide
information
to involve
condition
to reflect
generation
to identify
tool
to determine
generation
to locate
inclination
to compare
angle
Ex.8. Fill in the blanks choosing the proper word from those given above the texts.
(travels; layers; pulse; exploration; reflected; thickness; densities)
A seismic survey is usually the last … step before drilling a prospective site. Seismology
works because the earth’s crust has many … with different … and … . When seismic … from
the surface strikes the layers, part of it … through the layers and part of it is … back to the
surface.
(geophones; records; survey; seismogram; waves; artificially; a seismograph; cables)
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Seismic … starts with small … produced “earthquakes”. Sensors called … pick up the
reflected seismic … and send them through … to a recorder. The recorder, …, amplifies
(усиливает) and … their characteristics to produce a … .
Ex.9. Translate the following sentences into English.
1. Существует определенная зависимость между плотностью среды и скоростью
звука. Чем меньше плотность, тем больше скорость звука.
2. Чем больше разрешающая способность прибора, тем достовернее информация.
3. Чем больше опыта у интерпретатора, тем интереснее ему решать сложные
задачи.
4. Чем выше перепад давления, тем больше насыщение.
5. Чем больше тектонические силы, тем выше давление и температура,
затрагивающие породы.
Ex.10. Translate the sentences into Russian. Pay attention to the underlined words of the
same root.
1. It’s of great importance to estimate the likely amount of these resources.
2. These two substances exhibit like properties.
3. Fossils help us to imagine what some of the ancient plants and animals looked like.
4. Geological maps help geologists to find the rock structures most likely to contain oil
and gas deposits.
5. In some ways, the geologist is like a detective – he studies the evidence and work out
just what has happened.
6. William Smith found that like geological horizons have like fossilized remains.
7. By comparing the textures of the original and altered rocks often it becomes evident
that they were alike, and parts of the same body.
8. Subsurface mapping and interpretation of seismic data are likely to be the most
important tools for locating oil and gas bearing formations.
9. Anticlines unlike synclines are upfolded structures.
10. The analysis used production data for forecasting likely future well behavior.
11. Broadly speaking, the greater the water depth, the greater the likelihood of finding oil.
Ex.11. Translate the following sentences into English using the Infinitive as an adverbial
modifier of result.
1. Полученные данные недостаточно точны, чтобы можно было сделать
окончательный вывод.
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2. Рассматриваемый пример достаточно простой, и его можно применить в нашем
анализе.
3. Вопрос слишком трудный, чтобы сразу ответить на него.
4. Успехи в области интерпретации сейсмических данных слишком значительны,
чтобы их можно было описать в одном коротком сообщении.
Ex.12. Complete the following sentences.
1. Geophysics studies . . . .
2. Electrical survey deals with . . . .
3. Magnetic survey is the study of . . . .
4. Gravitational survey is concerned with . . . .
5. While conducting seismic survey geophysicists consider . . . .
Ex.13. Translate the following sentences into English. Use the active vocabulary of the Unit.
1. Общеизвестно, что поиск нефтегазоносных формаций сегодня немыслим без
применения геофизических методов, главным среди которых является
сейсморазведка.
2. Сейсморазведка – геофизический метод изучения геологических объектов с
помощью упругих волн - сейсмических волн.
3. Этот метод основан на том, что скорость распространения сейсмических волн
зависит от свойств геологической среды, в которой они распространяются:
состава пород, их пористости и др.
4. Эти и другие свойства проявляются в отражении, преломлении, дифракции и
поглощении сейсмических волн.
5. На грани раздела различных пластов волны как отражаются, так частично и
преломляются.
6. Горные породы отличаются по упругим свойствам и поэтому обладают
различными скоростями распространения упругих волн.
7. Методика сейсморазведки основана на изучении времени пробега (travel time)
различных волн от пункта их возбуждения до сейсмоприемников.
8. В сейсморазведке различают два основных метода: метод отраженных волн и
метод преломленных волн.
9. Сейсморазведка – очень важный и во многих случаях самый точный метод
геофизической разведки.
10. Главное назначение сейсморазведки – поиск структур, благоприятных для
накопления углеводородов.
Ex.14. Answer the questions.
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1. What does geophysics study?
2. What geophysical methods are employed in search for oil and gas?
3. How can the chances of drilling a dry hole be reduced?
4. What can magnetic surveying result in?
5. What is the field of application of electrical methods?
6. How are gravity measurements connected with seismic exploration?
7. Which is the most reliable geophysical method?
8. What does a seismic survey consist of?
9. What information is obtained through seismic survey?
10. What equipment is used in geophysical surveying?
Ex.15. Read the text and make a summary of it.
Geophysics is a study of the physics of the earth with special reference to its physical
properties, structure and composition. It is commonly divided into two general branches. The
first includes the subdivisions of the physical properties such as electricity, magnetism, heat,
elasticity, chemistry, etc. , while the second branch studies the three major components of the
earth: solid (lithosphere), liquid (hydrosphere), and gas (atmosphere).
Most underground structures can be diagnosed by geophysical methods. Thus the four
leading geophysical techniques relate to the four most common physical characteristics which
can be determined from the surface: magnetism, density, electrical conductivity, and elasticity,
which are investigated respectively by magnetic, gravitational, electrical, and seismic methods.
The development of seismic imaging in three dimensions greatly changed the nature of
hydrocarbon exploration. This technology uses traditional seismic imaging techniques, combined
with powerful computers and processors, to create a three-dimensional model of the subsurface
layers. 4-D seismology expands on this, by adding time as a dimension, allowing exploration
teams to observe how subsurface characteristics change over time. Exploration teams can now
identify hydrocarbon prospects more easily, place wells more effectively, reduce the number of
dry holes drilled, reduce drilling costs, and cut exploration time. This leads to both economic and
environmental benefits.
Ex.16. Translate the following text in writing. Use a dictionary.
Identifying and recovering hydrocarbons require an accurate, high resolution geological
model of the reservoir structure and stratigraphy.
Geological modeling is considered to be an applied science of creating computerized
representations of portions of the Earth’s crust, especially oil and gas fields and ground water
aquifers. In the oil and gas industry, realistic geologic models are required as input to reservoir
simulator programs to predict the behavior of the rocks under various hydrocarbon recovery
scenarios. An actual reservoir can only be developed and produced once, and mistakes can be
tragic and wasteful. Using reservoir simulation allows reservoir engineers to identify which
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recovery options offer the safest and most economic, efficient and effective development plan
for a particular reservoir.
Geological modeling is a relatively recent subdiscipline of geology which integrates
structural geology, sedimentology, stratigraphy, paleoclimatology and diagenesis. In 2
dimensions a geologic formation or unit is represented by a polygon, which can be bounded by
faults, unconformities or by its lateral extent, or crop. In geologic models a geologic unit is
bounded by 3 dimensional triangulated or gridded surfaces.
Ex.17. Agree or disagree with the following statements.
1. Geophysics studies physical fields of the earth.
2. Like rocks have like magnetic fields.
3. Electrical survey is of no importance in petroleum exploration.
4. Seismic survey is based on the gravitational field of the earth.
5. Seismic survey gives precise and reliable information about underground formations.
Ex.18. Speak on major methods of geophysical surveying. Use the following words and
word combinations.
Verbs: to measure; to be related to; to point to; to search for; to reduce; to apply; to enable; to
compare; to determine; to suggest; to record; to interpret; to reveal; to reflect; to refract; to
transmit; to analyze; to determine; to provide; to obtain.
Nouns and adjectives: physical qualities; magnetism; gravity; seismic vibrations; survey; oil and
gas bearing formations; subsurface conditions; slight differences; the location of formations;
configuration; flow of electricity; guidelines for a seismic exploration program; precise
information; seismic event; a seismic wave; interface between layers; hardness; density; an array
of receivers; inclination angles; subsurface reflectors; reflection amplitudes; attenuation.
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