In the oil and gas industry, the process of beginning to drill a well. Initially a larger drill bit is used to drill a surface hole, which is lined with casing and cement to protect groundwater. After the surface hole is completed, the main drill bit is inserted and the well is drilled to the total depth.

Can also be referred to as "spudding in".


Drilling for oil and gas is a highly complex task involving sophisticated techniques and machinery. It often costs hundreds of thousands of dollars to drill even a simple well. More difficult wells can cost millions of dollars. The most expensive wells are often found offshore, where high-end drilling platforms can cost over $500,000 per day in times of peak demand.

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  3. What factors are the primary drivers of share prices in the oil and gas sector?

    The primary drivers of share prices in the oil and gas sector are energy prices and economic growth. Stock prices in the ... Read Full Answer >>
  4. What impact does the growth in horizontal drilling have in the oil and gas sector?

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