Oil

 

Tri-Star produces West Texas Intermediate Crude from oil wells in the Permian Basin in the United States.  The company first began exploration of the Permian basin in Martin County, Texas in 1980. The West Texas Oil and Gas Company was formed in 1979 to develop drilling prospects in west Texas. The first crude oil was produced from Tri-Star’s Martin County in 1980. Tri-Star’s most recent well began production in November, 2013 in Kent County, Texas, following 30 years of exploration.

What is oil?

Oil is a fossil fuel formed from the decomposed remains of prehistoric remains of marine plants and animals. Over millions of years, layers of sediment, including sand and silt, cover the remains. These layers exert intense geological pressure and heat on the rock source, converting the organic matter to oil.

After oil is formed, it travels from the source rocks, through tiny pores in the surrounding rock until it either seeps through the rock onto the surface or is trapped beneath a layer of impermeable rock or clay and forms a reservoir. Reservoirs can be found anywhere from 10 to thousands of metres underground or under sea.

West Texas Intermediate (WTI) crude oil is a grade quoted in most economic announcements. WTI is also known as Texas Light Sweet because of its low density and sulphur content.

How is oil extracted?

Oil flows from the source rock where it was formed through porous reservoir rocks. Movements in the earth can trap the flow of oil between layers of cap rock, including granite or marble. To extract the trapped oil, a well is drilled and cased in stages until the final depth is reached. The casing is then perforated and a small diameter pipe is inserted to allow the oil to flow up the well. Production levels are set and a multi-valved structure is connected to control oil flow from the well. Depending on the type of reservoir, either acid or a special fluid containing proppants is used to commence the oil flow.