Preface. Peak oil was reached in November of 2018, but we aren’t out of oil, just halfway through.  Giant fields continue to be found, but in the deep ocean or arctic where it is expensive to drill. Below are some bits and pieces of what I could find about deepwater (>4,000 feet) and ultra deepwater (>7,000 feet).

We are not be running out of oil, but yikes, if we’ve had to resort to deep offshore drilling we must surely be desperate. Today about 30% of world oil production is in offshore wells. And they cost a lot: The Berkut rig in Russia was $12 billion dollars. And can take ten years before they start producing oil.

At least 90% of the oil reserves are state owned.  Meanwhile the private oil majors are running out of places to drill in the U.S., Europe, and other countries. Today their major drilling is: 43% Ultra-deepwater, 35% Deepwater, Shelf 7%, Land 14%. In 2023 they only found a billion barrels of oil, 68% less than the 3 billion barrels found in 2022.

Some offshore rig stats:

• Maersk Drilling’s Raya-1 well offshore Uruguay was drilled in water depths of 3,400 meters or 11,156 feet.
• Newfoundland Canada: Hibernia platform can withstand collisions of icebergs up to 1.1 million tons.
• Gulf: The Stones Floating production is the deepest operating oil and gas project reaching 9,500 feet below sea level.
• Gulf: Perdido moored in 8,000 feet of water and produces oil and gas from 7500 to 9500 feet, and was constructed by over 12,000 people
• The first oil well drilled in Texas in 1866 was a little over 100 feet deep: the No 1 Isaac C. Skillern struck oil at a depth that, from today’s perspective, is ridiculously shallow. In 1949, 4230 feet. And 10 years ago, the latest data from the Energy Information Administration shows, the average depth of U.S. exploration oil wells was almost 7,800 feet.
• The well in Angola’s Block 48 will be drilled at a new world record water depth of 3,628 meters. 11,903 feet

Alice Friedemann  www.energyskeptic.com  Author of Life After Fossil Fuels: A Reality Check on Alternative Energy; When Trucks Stop Running: Energy and the Future of Transportation”, Barriers to Making Algal Biofuels, & “Crunch! Whole Grain Artisan Chips and Crackers”.  Women in ecology  Podcasts: WGBH, Financial Sense, Jore, Planet: Critical, Crazy Town, Collapse Chronicles, Derrick Jensen, Practical Prepping, Kunstler 253 &278, Peak Prosperity,  Index of best energyskeptic posts

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Rystad Energy (2024) Upstream majors dive into deeper waters as exploration budgets stay flat in 2024

Conventional discoveries plunged in 2023, with majors hitting a bleak 1 billion barrels of oil equivalent (boe), shattering the post-2020 recovery trend and representing a stark 68% drop from the 3 billion boe in 2022. Notably, frontier basins, which contributed 45% of discoveries in 2022, only accounted for 20% last year.

Majors drilling activity by water depths 2023 (Shell, ExxonMobil, TotalEnergies, BP, Eni, Chevron:

43% Ultra-deepwater, 35% Deepwater, Shelf 7%, Land 14%

AI (2022) Offshore Drilling for Oil: How Does It Work Exactly? Arnold & Itkin

While the majority of crude oil is obtained from wells drilled on land, offshore production is crucial to keeping up with the ongoing petroleum demand. About 15% of U.S. oil production comes from offshore drilling operations in the Gulf of Mexico. About 30% of global oil production comes from offshore operations located in oceans and other bodies of water across the planet.

Because hundreds or thousands of feet of water lie between a drilling rig and the seafloor below, offshore oil production is far more expensive and challenging than oil and gas extraction on land.

Today’s offshore rigs are capable of drilling 250 miles from shore in waters up to 2 miles (10,560 feet) deep. What’s more, they can drill to depths of 28,000 feet below the seafloor. The deepest floating oil platform in the world is the Perdido, which is Spanish for “lost.” Operated by Shell, Chevron, and BP, the platform sits in 8,040-foot-deep water in the Gulf of Mexico. The Perdido is massive, with a structure that towers 876 feet above the water. The rig requires a crew of 172 people to operate it.

Once a potential oil reserve has been found, an exploratory well will be drilled. This is done with a Mobile Offshore Drilling Unit, or MODU, since finding oil is not guaranteed.

Jack-Up Rigs. These drilling platforms sit on three or four massive legs grounded to the ocean floor. Jack-up rigs are towed into position, and then the legs are lowered to the seafloor. Once all the legs are in place, the platform is raised up above the water to keep it safe from changing tides and ocean swells. Jack-up rigs typically operate at water depths of approximately 80 to 500 feet and may drill to depths of 5.6 miles or more below the seabed.

Semi-Submersible Rigs. Designed for offshore drilling in deep water, semi-submersible rigs are partially submerged during drilling operations and are moored with anchors (sometimes up to a dozen). These anchors are operated by computer systems that automatically adjust the tension on each chain to control drift, keeping the rig in place. Semi-submersibles may have their own propulsion systems to navigate to drilling sites, while others must be towed into place. These drilling rigs can operate in water depths of about 1,600 to 9,800 feet and can drill to depths of 6.2 miles or more below the seabed.

Drill Ships. Like semi-submersibles, drill ships are built for deep-water drilling. They are also mobile, able to navigate to the drill site on their own and then use a combination of anchors and propulsion to keep the vessel steady as it drills for oil. Drilling equipment is located on the top deck of a drill ship; the drill operates through a hole in the hull. Drill ships can operate in extremely deep water, at depths of about 1,600 to 11,975 feet and can drill to depths of 7.45+ miles below the seabed.

The following are the main types of production platforms:

• Fixed platforms, which typically operate in depths of up to 1,500 feet.
• Compliant towers, which are often used in depths of 1,000 to 2,000 feet.
• Tension leg platforms, which may be used in depths of up to 4,000 feet.
• Mini-tension leg platforms, which are used for smaller deep-water oil reserves.
• SPAR platforms, which currently drill in water depths of up to 3,000 feet.
• Floating production systems, which use semi-submersible units to drill in ultra-deepwater.
• Subsea systems, which are typically used in waters deeper than 5,000 feet.
• Floating production, storage, and offloading systems (FPSOs), which can drill and store oil before routinely offloading it using smaller shuttle tankers that take it to shore for processing

These offshore production platforms are responsible for extracting and processing crude oil from the rock formations below the seabed. They contain all the equipment and crew members necessary to keep offshore oilfields in production, process oil that has been extracted, and transport it to the coast. Offshore platforms are massive and complex, sometimes requiring more than 100 workers to operate. Because many of these rigs are located miles from shore, crews must remain on board, living and working on the platform for weeks at a time.

Extensive pipeline systems are used to transport oil from platforms to the coast for processing and distribution. Infield pipelines, often referred to as feeder lines or flowlines, are used to transport a mixture of oil, gas, and water from subsea wells to platforms. Export pipelines move processed oil or gas from a platform to the coast.