10.1 Remember the meaning of the following words and word-combinations:

reservoir – коллектор

to settle - оседать, опускаться

silt – ил, наносы

layer – слой

to pile up – накапливаться

sea bottom – морское дно

geologic shift – геологический сдвиг

to result in – приводить к ч-л

over time – со временем

source rock – нефтематеринская порода

sponge – губка

to seep out – просачиваться, выходить на поверхность

permeable rock - проницаемая порода

offshore well – морская скважина

to penetrate - проходить через , проницать

gravity – 1) сила тяжести 2) плотность

to separate – отделять

gravitational separation – гравитационное разделение ( флюидов различной плотности под действием силы тяжести)

density – плотность

solubility – растворимость

to restrict – ограничивать

to locate – определять место, местонахождение

mature - старое, давно разрабатываемое (месторождение)

to access – доходить до, достигать

band – слой

seismic technique – метод сейсмической разведки

3D = 3 dimensional - трехмерный, объемный

odds - шансы

remote areas – отдаленные территории

10.2 Read and translate the following text using a dictionary:

What is an Oil and Natural Gas Reservoir?

Oil and natural gas were formed from the remains of prehistoric plants and animals. Hundreds of mil­lions of years ago, prehistoric plant and animal remains settled into the seas along with sand, silt, and rocks. As the rocks and silt settled, layer upon layer piled up in rivers, along coastlines, and on the sea bottom. Geologic shifts resulted in some of these layers being buried deep in the earth. Over time, the layers of organic material were compressed under the weight of the sediments above them, and the in­creasing pressure and temperature changed the mud, sand, and silt into rock and the organic matter into petroleum. This rock containing the organic matter that turned into petroleum is referred to as source rock. The oil and natural gas is contained in the tiny pore spaces in these source rocks, similar to water in a sponge.

Over millions of years, the oil and gas that formed in the source rock deep within the earth moved up­ward through tiny, connected pore spaces in the rocks. Some seeped out at the surface of the earth. But most of the petroleum hydrocarbons were trapped by nonporous rocks or other barriers that would not allow it to migrate any further. These underground traps of oil and gas are called reservoirs. Reservoirs are not underground "lakes" of oil; reservoirs are made up of porous and permeable rocks that can hold significant amounts of oil and gas within their pore spaces. The properties of these rocks allow the oil and natural gas within them to flow through the pore spaces to a producing well.

Some reservoirs may be only hundreds of feet below the surface. Others are thousands, and sometimes tens of thousands of feet underground. In the U.S., a few reservoirs have been discovered at depths greater than 30,000 feet (9.15 km). Many offshore wells are drilled in thousands of feet of water and penetrate tens of thousands of feet into the sediments below the sea floor.

Most reservoirs contain oil, gas, and water. Gravity acts on the fluids to try to separate them in the res­ervoir according to their density, with gas being on top, then oil, then water. However, other parame­ters, such as fluid/rock properties and solubility will restrict complete gravitational separation. When a well produces fluids from a subsurface reservoir, typically oil and water, and often some gas will be recovered.

The larger subsurface traps are the easiest deposits of oil and gas to locate. In mature production areas of the world, most of these large deposits of oil and gas have already been found, and many have been producing since the 1960s and 1970s. The oil and gas industry has developed new technology to iden­tify and access smaller, thinner bands of reservoir rock that may contain oil and gas. Improved seismic techniques (such as 3D seismic) have improved the odds of correctly identifying the location of these smaller and more difficult to find reservoirs. There is still a lot of oil and gas left to be discovered and produced. Future discoveries will be in deeper basins, and in more remote areas of the earth. There will also be a lot of small reservoirs found in existing oil and gas areas using advanced technologies.

10.3. Answer the questions on the text:

1. What rock is referred to as source rock? 2) Where are oil and natural gas

contained? 3) How are petroleum hydrocarbons trapped? 4) What is an oil reservoir? 5) What rocks is a reservoir made of? 6) How deep below the surface are the reservoirs? 7) Why are oil, gas and water separated in a reservoir? 8) What is there on top of a reservoir? 9) What factors restrict complete gravitational separation? 10) What deposits are the easiest to locate? 11) Why are new technologies being developed? 12) What techniques have improved the odds of correctly identifying the location of smaller reservoirs? 13) Where will future discoveries of oil and gas take place?

10.4. Give English equivalents of the following word-combinations from the text:

накапливаться слой за слоем, со временем, называться нефте-

материнской породой, мельчайшее поровое пространство, перемещаться дальше, морские скважины, в зависимости от плотности, растворимость; территории, где давно ведется добыча (нефти/газа), распознавать и доходить до, более тонкие пласты, усовершенствованная техника, отдаленные территории

10.5. Complete the sentences in column A choosing the correct ending from

column B:

A B

1) Oil and natural gas were formed from … a) large amounts of fluids in their

pore spaces.

2) The layers of organic material were com- b) in remote areas of the earth.

pressed ……..

3) The source rock within the earth has c) according to their density.

got ………..

4) Underground traps of oil and gas are d) the remains of prehistoric plants

called ……….. and animals.

5) Reservoirs can hold ……….. e) reservoirs.

6) Fluids in a reservoir are separated ……. f) tiny pore spaces that contain oil

and natural gas.

7) New technologies allow to identify and g) under the weight of the sediments

access ………….

8) Future discoveries will take place …… h) thinner bands of reservoir rock.

10.6. Choose the only correct variant to fill in the gaps:

1) Rocks and silt settled layer upon layer over …………… .

a) tiny pore spaces b) the remains of plants and animals

c) the source rock d) permeable rock

2) The source rock contains oil and natural gas in ………….. .

a) underground lakes b) a sponge

c) tiny pore spaces d) geological shifts

3) Below the surface the petroleum hydrocarbons …………. by nonporous rocks.

a) are produced b) are allowed c) are penetrated d) are trapped

4) ………. reservoirs have been discovered at 9 kilometers depth.

a) a lot of b) some c) many d) plenty of

5) Fluids are separated in the reservoir because of …………. .

a) gravity b) water c) pressure d) temperature

6) In a reservoir …….. is usually on top, then ……, then ……. .

a) water, gas, oil b) oil, water, gas

c) gas, water, oil d) gas, oil, water

7) 3D seismic allows production engineer to identify and access …………. .

a) the sea floor b) thinner bands of reservoir rocks

c) remote areas of the earth d) mature production areas

10.7. Give the summary of the text about oil and natural gas reservoirs using the

following word-combinations:

Remains of prehistoric plants and animals, be compressed under the weight of sediments, source rock, be trapped by nonporous rocks, to form a reservoir, of different depth, gravity, to separate according to density, to locate subsurface traps, to develop new technologies, to identify and access thinner bands of reservoir rock, remote areas of the earth.

UNIT 11 EXPLORATION METHODS AND TECHNIQUES

11.1. Remember the meaning of the following words:

anticline - антиклиналь, антиклинальная складка (куполовидная складка,

крылья которой падают в противоположных направлениях)

survey - изыскание; съёмка; разведка; профилирование; картирование;

геофизические исследования; производить съёмку

exploration - поисково-разведочные работы; разведка месторождения;

изыскательские работы

gravity anomalies – гравитационные аномалии

magnetic anomalies - магнитная аномалия

seismic grid - сетка сейсмических профилей

public domain - всеобщее достояние; государственная собственность accumulation - аккумуляция; скопление; накопление; залежь;

месторождение (нефти, газа); формирование залежи

investigation - изучение; исследование; обследование (месторождения)

validity – истинность; достоверность; обоснованность; доказанность

onshore seismics - наземная сейсмическая разведка

offshore – морской

folded – складчатый

mapping - составление карты, картографирование, картирование; геодезическая съёмка

prospect - перспективная площадь; разведка; изыскание

wildcat - скважина, заложенная без предварительного геолого-

геофизического обоснования; опорно-геологическая скважина;

разведочная скважина

crude – нефть, «сырая нефть»

lead - продуктивный пояс месторождения

mud - буровой раствор; промывочная жидкость; буровая грязь

play - длина нефтеносного пласта

to develop - подготавливать месторождение к эксплуатации; разрабатывать

(месторождение)

environmental impact assessment - экологическая экспертиза, оценка

воздействия на окружающую среду

11.2. Read and translate the text using a dictionary.

Exploration Methods and Techniques

From the drilling of Drake's well in Pennsylvania in 1859 until far into the twentieth century, wells were sunk close to seepages - what is now known as "seepage drilling” - but there was no exploration in the modern sense until geology was applied to the finding of oil in the late nineteenth century. In 1885 several new fields were discovered on the basis of the theory that oil accumulates in the crests of folded rock layers, known to geologists as anticlines.

The first employment of a geologist by an oil company appears to have been in 1897, but not until the discovery of the Cushing Field, Oklahoma, in 1912 as a result of geological survey did geo­logists enter the industry in any numbers. Soon afterwards, however, many hundreds were roaming all over the USA and other countries in search of anticlines. The period from 1912 to 1925, during which most of the principal anticlines in the USA were discovered, is known as the "anticlinal period", the end of which marks the beginning of modern scientific exploration.

The objective of any exploration venture is to find new volumes of hydrocarbons at a low cost and in a short period of time. Exploration budgets are in direct competition with acquisition opportunities. If a company spends more money finding oil than it would have had to spend buying the equivalent amount "in the market place" there is little incentive to continue exploration. Conversely, a company which manages to find new reserves at low cost has a significant competitive edge since it can afford more exploration, find and develop reservoirs more profitably, and can target and develop smaller prospects.

The usual sequence of activities once an area has been selected for exploration starts with the definition of a basin. The mapping of gravity anomalies and magnetic anomalies will be the first two methods applied. In many cases today these data will be available in the public domain or can be bought as a "non exclusive" survey. Next, a coarse two-dimensional (2D) seismic grid, covering a wide area, will be acquired in order to define leads, areas which show for instance a structure which potentially could contain an accumulation. A particular exploration concept, often the idea of an individual or a team will emerge next. Since at this point very few hard facts are available to judge the merit of these ideas they are often referred to as "play". More detailed investigations will be integrated to define a prospect; a subsurface structure with a reasonable probability of containing all the elements of a petroleum accumulation.

Eventually, only the drilling of an exploration well will prove the validity of the concept. A wildcat is drilled in a region with no prior well control. Wells may either result in discoveries of oil and gas, or they find the objective zone water bearing in which case they are termed "dry".

Exploration activities are potentially damaging to the environment. The cutting down of trees in preparation for an onshore seismic survey may result in severe soil erosion in years to come. Offshore, fragile ecological systems such as reefs can be permanently damaged by spills of crude or mud chemicals. Responsible companies will therefore carry out an Environmental Impact Assessment (EIA) prior to activity planning and draw up contingency plans should an accident occur.

11.3. Answer the questions on the text:

1. When was geology first applied to the finding of oil? 2. Why is the period from 1912 to 1925 known as the “anticlinal period”? 3. What does the end of the "anticlinal period" mark? 4. What is the objective of any exploration venture? 5. Are exploration budgets in direct competition with acquisition opportunities? Why? 6. What is the usual sequence of exploration activities? 7. What are the first two methods applied? 8. What is acquired in order to define leads? What is a lead? 9. What is often referred to as "play"? 10.What is a prospect? 11.What proves the validity of the exploration concept? 12. Why are exploration activities potentially damaging to the environment?

11.4. Translate the following words and phrases into English:

на основе теории; сводовая часть складки; путешествовать, скитаться, странствовать; цель любых поисково-разведочных работ; по низкой цене; приобретение, покупка; стимул; конкурентное преимущество, отличие; гравитационные и магнитные аномалии; быть общедоступным; неопровержимые факты; месторождение нефти; обычная последовательность действий; двухмерная сетка сейсмических профилей; разведочная скважина; наземная сейсмическая разведка; привести к сильной эрозии почв, разлив нефти; химикат, химический продукт, химреагент; составлять план работ в аварийной ситуации.

11.5. Complete these sentences with a suitable word or phrase from the text:

1. Responsible companies carry out ________prior to activity planning.

2. _______, covering a wide area, is acquired in order to define leads.

3. A prospect is a subsurface structure with a reasonable probability of containing all the elements of __________.

4. The cutting down of trees in preparation for _______survey may result in severe soil erosion in years to come.

5. Only the drilling of _______proves the validity of the exploration concept.

6. ________ are areas which show a structure which potentially could contain an accumulation.

7. The first two exploration methods are_________.

8. The objective of any exploration venture is to find new volumes of ______at a low cost and in a short period of time.

9. Not until the _______of the Cushing Field, Oklahoma, in 1912 as a result of geological survey did geo­logists enter the industry in any numbers.

10. In 1885 several new fields were discovered on the basis of the theory that oil accumulates in the crests of folded rock layers, known to geologists as_______.

11.6. Say whether the following sentences are true (T) or false (F).

1. From the drilling of Drake's well in Pennsylvania in 1859 until far into the twentieth century, wells were sunk close to seepages - what is now known as "anticlinal period".

2. An oil company first employed a geologist in 1897.

3. Exploration budgets are related to acquisition opportunities.

4. A coarse three-dimensional (3D) seismic grid, covering a wide area, is acquired in order to define leads.

5. An exploration well is drilled in a region with no prior well control.

6. Responsible companies carry out an Energy Information Assessment (EIA) before activity planning and draw up contingency plans if an accident occurs.

7. Exploration activities may cause damage to the environment.

8. The drilling of an exploration well always results in discoveries of oil and gas

11.7. Retell the text, using the questions from exercise 3 as a plan.

UNIT 12 DRILLLING THE WELL