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.

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