Match the words in A with the words in B to make collocations.

1. reflection	A. surveying
2. geothermal	B. method
3. groundwater	C. wave
4. ground-penetrating	D. energy
5. accurate	E. operation
6. solve	F. radar
7. reduce	G. acquisition
8. exploration	H. seismology
9. shear	I. problem
10. data	J. uncertainties

Fill in the gaps with correct prepositions.

1. Reflection seismology is used ____ basic research into the nature and origin ____ the rocks.

2. GPR is widely used ____ mapping shallow subsurface ____ ___ a few meters deep.

3. 3D-seismic technology is applied to reduce uncertainties _____ the entire range ____ exploration, development and production operations.

4. These chimneys are caused ____free gas ___ the sediments.

5. Combining P- and S-waves discriminate _____ sands and shales and is valuable ___ helping to detect fractures.

Make up sentences, adding words where necessary.

1. reflection/ accurate/ is/ at present/ the most/ seismology/ method.

2. applied/ to/ uncertainties/ 3D-seimic/ technology/ is reduce.

3. includes/ and/ waves/ full-vector wave-field imaging/ shear/ compressional.

4. economically/ gas/ plague/ chimneys/ areas/ important.

5. used/ exploration/ reflection seismology/ for/ extensively/ is/ hydrocarbons/in.

Fill in the gaps with words which are derived from the word given at the end of each line.

1. The technology of exploration activities has improved exponentially because of …………. in data processing and interpretation	ADVANCE
2. ….. in geophysical measurements can cost a lot of money.	CERTAIN
3. Numerous factors such as subsurface geology, terrain, security issues determine parameters for data …………….	ACQUIRE
4. As S-waves can travel only through a solid, they are …….. to the type of a fluid in the rock.	SENSITIVE
5. ….. Vice President refers to a rank in senior management and usually reports directly to the President of the company and could be more than one in different areas (Upstream, Downstream, Oilfield services)	EXECUTE
6. It is difficult to overestimate ………. of 3D seismic technology for hydrocarbon exploration, development and production operations.	CAPABLE
7. Primary waves are ………. waves that travel quicker in dense rock and slower in fluids.	COPMRESS
8. Gold and uranium as well as other ores are ……….. mineral resources.	VALUE
9. Upstream provides a …….. supply of petroleum for consumers downstream	CONTINUE
10. If the economic penalties of ………. in depth investigations are substantial, it may be cheaper to perform exploratory drilling.	ACCURACY

State whether the following sentences are True or False; correct the false ones.

1. Ground-penetrating radar is widely used to reduce uncertainties across the full range of exploration and production operations.

2. Gas chimneys are extremely useful for economically important areas.

3. Reflection seismology is applied in deep groundwater surveying.

4. The least accurate method of determining depths formation is reflection method.

5. Surveys are used to execute oil-recovery strategies and monitor fluid movement in reservoirs.

6. Geophysicists combine refraction and reflection methods to discriminate among sands and shales.

7. GPR is widely used for mapping shallow subsurface.

You will hear the report on seismic waves. Match the terms with their descriptions. One of them is extra.

1. Body waves	awaves that travel in a circular motion and cause damage by displacing material
2. Secondary waves	b waves propagating along the surface and deforming the material vertically
3. Primary wave shadow zone	c waves that travel through the interior of the earth
4. Secondary wave shadow zone	d waves that are deflected by the Earth’s core forming a special area
5. Love waves	e waves that travel only through solids thus they do not penetrate the Earth’s outer core forming a special zone
6. Rayleigh waves	f waves that move sideways at right angles to the direction of travel
	g waves that do not penetrate the earth’s interior but follow the surface

Answer the following questions.

1. What are the three main applications of reflection seismology?

2. Which method is similar to reflection seismology?

3. When is the GPR method applied?

4. Which method is applied to determine the depths of formations in exploration of petroleum?

5. What are three operations when 3D-seismic technology is applied?

6. What are the capabilities of 3D-seismic technology?

7. What is S-wave?

8. What is P-wave?

9. What does full-vector wave-field imaging help to “see”?

10. When is the combination of P- and S-waves applied?

29. For the gaps 1 – 5, 6 - 10, choose one of the words on the right (1 -6) that best completes the gap in the text. You can use each word only once. For every 5 gaps, there is one extra word.

Ground Penetrating Radar
The depth range of GPR is limited by the electrical (1) ______ of the ground, and the transmitting frequency. As conductivity increases, the penetration depth (2) ______. This is because the electromagnetic energy is more quickly dissipated into heat energy, causing a loss in signal (3) __________at depth. Higher frequencies do not (4) ________as far as lower frequencies, but give better resolution. Optimal depth penetration is achieved in dry sandy soils or massive dry materials such as granite, (5) ____________, and concrete where the depth of penetration is up to 15 m. In moist and/or clay laden soils and soils with high electrical conductivity, penetration is sometimes only a few centimetres.	1. limestone
2. decreases
3. conductivity
4. penetrate
5. positions
6. strength
GPR uses transmitting and receiving antennae. The transmitting antenna radiates short pulses of the (6) _________ (usually polarized) radio waves into the ground. When the wave (7) _________ a buried object or a boundary with different dielectric constants, the receiving antenna records (8) __________ in the reflected return signal. The principles involved are similar to (9) ____________ seismology, except that electromagnetic energy is used instead of acoustic energy, and reflections appear at boundaries with different dielectric constants instead of acoustic (10) __________.	1. dimensional
2.impedances
3.high-frequency
4. encounters
5. variations
6. reflection

Terms and Vocabulary

pattern	cтруктура; график
obtain	получать, приобретать, достигать
sequence	последовательность, ряд
tow	тянуть на буксире, буксировать
echo-sounding	акустическое зондирование
undertake (took, taken)	предпринимать, выполнять, осуществлять
submerge	погружать(ся), покрывать(ся) водой, затоплять, тонуть
burst	подрыв
pass	передавать
echo	отраженный звук, сигнал, отголосок
reach	достигать
ray path	траектория луча
two-way travel time	полное время пробега, время прохождения сигнала в прямом и обратном напраслении
pulse	импульс, вибрация
hemispherical wave front	полусферический волновой фронт, головная часть волны
intercept	улавливать, выделять, перехватывать
space	расставлять, располагать с определенным интервалом
graph	график; диаграмма; кривая; годограф
plot	представлять данные графически; строить (график, диаграмму, кривые)
wiggle	покачивание, отклонение
wiggle trace	трасса, визуализированная способом отклонений
peak	вершина кривой, высшая точка; максимум
trough	прогиб, низшая точка, минимум
magnitude	величина
deflection	отклонение от прямой, прогибание
convention	условное обозначение, договоренность
dual polarity	двойная полярность
display (n,v)	визуальное представление данных, изображение (на экране); показывать, демонстрировать, изображать
wiggle variable area display	изображение, полученное способом отклонений с зачернением положительных амплитуд
variable density display	изображение, полученное способом переменной плотности
variable area data	данные, полученные способом переменной площади
common depth point	общая глубинная точка
vessel	судно
time	выбирать время; рассчитывать (по времени); упорядочивать, синхронизировать во времени
separation	расстояние между ….., интервал
summing	накапливание; накопление
CDP gather	сейсмограмма ОГТ; сейсмограмма общей глубинной точки
hyperbolic curve	гиперболическая кривая
normal move out (NMO)	поправка за нормальное приращение времени
alignment	выравнивание (плоскости, кривой; установка на одном уровне
stack	комплектовать
stacking	суммирование, накапливание трасс
cause	вызывать, заставлять, побуждать
random noise	случайная помеха
cancel out	уничтожаться, взаимно исключаться
seismic section	сейсмический разрез, профиль
seismic line	профиль
time-section	сейсмопрофиль во временах
subtle	трудноуловимый
depth-section	глубинный разрез
traverse	пересекать
convert	преобразовывать
obscure	затемнять, мешать, делать неясным
intrinsic deficiencies	внутренне присущий (естественный) недостаток
multiple	кратноотраженная волна
ringing	реверберация
diffraction	отгибание, дифракционная волна
mimic	имитировать, воспроизводить
arched formations	антиклинально построенные структуры, сводообразная структура
deconvolution	обратная фильтрация, деконволюция
counteract	противодествовать, препятствовать, нейтрализовать
blurring	искажение, нечеткость, затуманивание
spike	импульс, импульсное искажение, отскок
suppression	подавление
incline	наклонять, падать
muting	обнуление части трасс
embody	заключать в себе, содержать
remove	удалять, устранять
collapse	ослаблять, рушить

Pay attention to the pronunciation of the following words and word-combinations.

echo-sounding	minute	trough
axis	oil-bearing	amplitude
interpret	cause	intrinsic deficiencies
obscure	arched formation	blurring
counteract	collapse	society
pattern	occur	deconvolution
hyperbolic curve	alignment	traverse
via	subtle	towards
incline	distortion	submerge

Pay attention to the structure of the words and give their Russian equivalents.

bury-burial	slight-slightly
direct-direction	relate-relative-relatively
correct-correction	desire-desirable-undesirable
suppress-suppression	expensive-inexpensive
migrate-migration	vary-variable-invariable-invariably
pulse-pulsation	indicate-indication-indicator
filter-filtering	locate-relocate
polar-polarity	compress-recompress
distort-distortion	move-movement-remove-motion

Make up word-combinations

1. tow	a wave front
2. undertake	b ray path
3. submerge	c echo-sounding
4. intercept	d pulse
5. space	e hyperbolic curve
6. plot	f wiggle trace
7. time	g two-way time
8. display	h vessel

33. Read the text and do the exercises.

Acquisition

Large-scale geological structures that might hold oil or gas reservoirs are invariably located beneath non-productive rocks, and in addition this is often below the sea. Geophysical methods can penetrate them to produce a picture of the pattern of the hidden rocks. Relatively inexpensive gravity and geomagnetic surveys can identify potentially oil-bearing sedimentary basins, but costly seismic surveys are essential to discover oil and gas bearing structures.

More detailed information about the rock layers within such an area can be obtained by deep echo-sounding, or seismic reflection surveys. In offshore areas these surveys are undertaken by a ship towing both a submerged air or water gun array, to produce short bursts of sound energy, and a set of streamers of several kilometres length. Each streamer contains a dense array of hydrophone groups that collect and pass to recorders echoes of sound from reflecting layers. The depths of the reflecting layers are calculated from the time taken for the sound to reach the hydrophones via the reflector; this is known as the two-way travel time. The pulse of sound from the guns radiates out as a hemispherical wave front, a portion of which will be reflected back towards the hydrophones from rock interfaces. The path of the minute portion of the reflected wave-front intercepted by a hydrophone group is called a ray path. Hydrophone groups spaced along the streamer pick out ray paths that can be spaced to specific points on the reflector surface. Graphs of the intensity of the recorded sound plotted against the two-way time are displayed as wiggle traces, in which each trace represents a geophone on the surface. Peaks and troughs on the wiggle represent up and down movements of the geophone, in which the vertical axis of the wiggle is two-way time, and the amplitude of the peak or trough indicates the magnitude of geophone movement. Generally, peaks face right and are colored black to make it easier to interpret the line. In variable density displays, shades of gray are used to represent amplitude instead of peak/trough deflection.

The Society of Economic Geophysicists has a convention that troughs represent upward motions of the ground and peaks represent downward motions. However, many companies have their own conventions. At shallow burial depths, troughs (upward expansion) represent low-velocity sands, peaks (downward troughs) are high-velocity shales. With greater burial, sands become faster than shales, and troughs will switch to represent shales.

Today, dual-polarity displays of variable area data are common, where troughs are colored red to indicate low-velocity sands at shallow depths, peaks are colored black (to indicate high-velocity shales, and transitions between peaks and troughs are not shown at all. The troughs are then reversed, and superimposed on the original traces so that both peaks and troughs face the same direction. Dual polarity displays of variable density are also common.

Seismic recording at sea always uses the common depth point (CDP) method. A sequence of regularly spaced seismic shots is made as the survey vessel accurately navigates its course. Shots are usually timed to occur at distances equal to the separation of the hydrophone groups. In this way up to 120 recordings of the echoes from any one of 240 reflecting points can be collected. Each represents sound, which has followed a slightly different ray path, but has all been reflected from the same common depth point.

(Discovering the Underground Structure http://www.ukooa.org/education/storyofoil/index.cfm)

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