Finding the oil
Ex.1Read the text and answer the questions.
1. What must an oil company begin with before drilling a hole?
2. How can a geologist find out what shape the rocks under the earth's surface have?
3. What is a geological cross-section?
4. When does the job of experts at studying rocks become much harder?
5. What method is most popular to find oil when the conditions of drawing accurate geological cross-sections are very hard?
Locate (v) - определять местонахождение
Cross-section - поперечное сечение (разрез)
Survey (n) – съемка, промер, изыскание
Drill a hole - бурить скважину
Oil is found underground, which makes locating it a difficult job. What is the best way to find it? Drill a hole and hope for the best? This is one way, but when you consider that it can cost anything up to £1 million just to drill one well on land and up to £3 million under the sea, then this method might not seem such a good idea.
The first thing that an oil company will do is to discover what types of rock there are underground, and also whether the rocks are folded or faulted. In other words the oil company wants to know if it is likely that there are some oil traps underground. There are two main ways of doing this. To start with, geologists, who are experts at studying rocks, look closely at an area and find out what types of rock there are. By accurately measuring the angle at which the rocks disappear underground the geologist can build up a picture of how the rocks are shaped beneath the surface. After a great deal of measurement the geologist can make a detailed picture of what the rocks are like under the earth's surface. This is known as a geological cross-section. As you can imagine, it would take geologists a long time to draw accurate geological cross-sections for all the places where there may be oil. If the rocks are very deep or if they are arranged in a complicated way the job is even harder. Because of this, oil companies use other ways of trying to find oil. The most common method is known as seismic survey.
I. Tell your fellow-students where oil can be found.
II. Tell your fellow-students where new oilfields have recently been discovered.
III. Tell your fellow-students what experts take part in finding oil.