Unit 11 How does the industry find oil and natural gas

Words to be remembered:

to look for – искать

oil seeps – просачивание, выход нефти на поверхность

outcrop - обнажаться, выходить на поверхность; выход (пласта или залежи),

           обнажение пород

"hit or miss" – ‘пан или пропал’; либо угадал, либо нет

seismic - сейсмический 

to reflect – отражать

reflection – отражение

formation – пласт

to set geophones – устанавливать сейсмоприемники

crew – бригада

grid pattern - размещение (скважин) в виде решетки, сетки

exploratory well – разведочная, поисковая скважина

commercial – промышленный 

sound wave - звуковая волна 

two-(three-)dimensional – двухмерный (трёхмерный) 

2-D image -двумерное (плоское) изображение

3-D image трёхмерное (объёмное) изображение 

to process – обрабатывать (данные) 

to drill – бурить 

seismic image - сейсмическое изображение

offshore well – морская скважина    

onshore well – наземная скважина

 

Through the early 1900s, finding oil and gas was largely a matter of luck. Early explorers looked for oil seeps to the surface, certain types of rock outcrops, and other surface signs that oil might exist below ground. This was a "hit or miss" process.

But science and technology quickly developed to improve the industry's ability to "see" what lies below ground. Seismic technology uses the reflection of sound waves to identify subsurface formations. A crew working on the surface sets geophones at intervals along a straight line. Then a loud noise is created at the surface. The noise moves through the ground and reflects off of underground formations. How quickly and loudly that sound is reflected to the geophones indicates what lies below ground. This process is repeated many times. Different types of formations reflect sound differently, providing a picture of the types of rocks that lie below. If the geophones are laid out in straight lines, the results are called 2-dimensional (2D) seismic. If they are in a grid pattern, the result is called 3-dimensional (3D) seismic. Reading 2D seismic images to find possible traps and reservoir rocks was as much art as science. Today, sophisticated technology and high-speed computers help geophysicists process massive amounts of seismic data. From these data, they can develop three-dimensional underground maps that significantly improve the industry's ability to locate possible oil or gas deposits. But until a well is drilled, it is impossible to know for certain whether the resource is there, whether it is oil or gas, and whether it can be recovered in commercial quantities.

Once a company identifies where the oil or gas may be located, it then begins planning to drill an exploratory well. Drilling a well is expensive; shallow offshore wells or deep onshore wells can cost more than U.S.$10 million each to drill. In deep water offshore, or in remote areas such as the Arctic, wells can cost substantially more. Companies must analyze all of the available information in determining whether, and where, to drill an exploration well.

Even with the best technology, drilling a well does not always mean that oil or gas will be found. If oil or gas is not found in commercial quantities, the well is called a dry hole; it will be plugged with cement. Sometimes, the well encounters oil or gas, but the reservoir is determined to be unlikely to produce in commercial quantities.

New and better technology has made it possible for the industry to continue finding oil and gas with fewer wells, less waste, less surface disturbance, and greater efficiency.

 

Questions on the text:

  1) How did early explorers find oil and gas? 2) What is seismic technology? 3) How does seismic technology work? 4) What results do geophysicists get if the geophones are laid out in straight lines? 5) How can geophysicists develop three-dimensional underground maps? 6) When does a company begin planning to drill an exploratory well? 7) Is drilling a well expensive? 8) How much does it cost to drill a well? 9) What is a dry hole? 10) What happens to a dry hole? 11) What has enabled the industry to find oil and gas with fewer wells?