Onshore and offshore drilling are two methods used by companies in the oil and gas industry to obtain gas and oil. Onshore drilling is done on land, while offshore drilling is done in a remote location off the shore over the water. The rigs used in onshore drilling are moved in by ground transportation, and many times multiple wells are being drilled from the same site in very close proximity to each other by shifting the rig slightly. Onshore drilling profiles vary from shallow to deep wells, extended reach to ultra-extended reach wells, and vertical to deviated wells. On the other hand, offshore drilling is done in a remote location off the shore over the water, and operators drill below the earth’s seabed as deep as 12,000 feet. These wells are drilled using slender steel pipes and other tools that connect to make a drill sting. Each pipe is about 30 feet long, and as the well is drilled deeper, more pipes are added to the drill sting.
Some key differences between onshore and offshore drilling include:
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Location: Onshore drilling takes place on land, while offshore drilling occurs in a remote location off the shore over the water.
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Accessibility: Onshore drilling is more accessible for crews to arrive and depart from the site, while offshore drilling requires rig setups that take many years to build and is extremely costly to invest in before oil and gas are found.
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Equipment: The equipment used in both operations is almost similar, apart from the drilling platform in onshore drilling, which is somewhat different. Offshore sites feature derricks, crew quarters, and production facilities.
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Production: Most of the crude oil production in the world comes from onshore drilling, as opposed to offshore.
It is important to note that working in the oil and gas industry is dangerous, and both onshore and offshore drilling represent some of the most hazardous lines of work across all occupations. Adding a huge body of water to the extraction equation doesn’t necessarily make offshore drilling any riskier than onshore operations, but it does make the risks different in nature.
