When the well reaches a pool, oil usually rises up the well because of its density difference with water beneath it or because of the pressure of expanding gas trapped above it.

当井和一个水池相接时，油通常会从井里上升，因为它与井下的水的密度不同，或者因为停留在它上方的膨胀气体的压力。

youdao

Both oil and gas are less dense than water, so they generally tend to rise upward through water-saturated rock and sediment.

石油和天然气的密度都比水小，所以二者通常会浮在被水浸泡的岩石和沉积物的表层。

youdao

The water would exert less pressure on the oil and gas down below, which is why it was important that 【concrete seals】 were in place to avoid any blowout.

因为海水对石油以及井下的天然气造成的压力更小，所以为避免任何喷发，及时用【海水代替泥浆】封堵井口是至关重要的。

youdao

The three groups are Power and Water, Oil and Gas, and Energy Management.

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