hsw - offshore drilling

8/6/2019 HSW - Offshore Drilling

http://slidepdf.com/reader/full/hsw-offshore-drilling 1/6

How Offshore Drilling Worksby Robert Lamb

Brow se the article How Offshore Drilling Works

Oil Field Image Gallery

Arnulf Husmo/Stone/Getty Images

Offshore oil platform 'Gullfaks C' stands up to a fierce, North Seastorm. In this part of the world, waves frequently reach as high as 6

feet (2 meters). See more pictures of oil fields and drilling.

Up Next

Oil Shale Quiz

How Oil Drilling Works

Curiosity Project:

Polymer-based Products

You Use Every Day

Introduction to How Offshore Drilling Works

Some people say money makes the world go round. Others insis t the key ingredient is love or

even music. But whatever drives humanity to carry on from day to day, our dependence on

fossil fuels leaves one fact for certain: The axle of our spinning globe is g reased with oil.

We consume m ore than 80 m illion barrels of the stuff every day [source: CIA]. To meet our

ravenous demand for fossil fuels , petroleum companies constantly comb the planet for new

reserves. Since oceans cover nearly three-quarters of Earth's surface, a great deal of those

reserves wind up underwater.

Reaching these unders ea drilling s ites poses quite a challenge. After all, drilling on land is

an undertaking on its own . How do you drill in lightless oce an depths and transport all that

liquid, gas and s olid petroleum back to the surface? How do you keep from polluting the

ocean? And how do you do all of this, with tons of special equipm ent, in the middle of rough

seas?

To surmount these obstacles, petroleum companies

have invested billions into the development of

offshore drilling and offshore oil platforms. The first

of these platforms was constructed in 1897 at the

end of a wharf in California. In the years to follow, oil

prospectors pushed ou t into the ocean, first on piers

and then on artificial isl ands. In 1928, a Texan

oilman unveiled the first mobile oil platform for drilling in wetlands . The structure was li ttle more than a barge with a drilling outfit

moun ted on top, but it set the example for decades of advancements to come.

In the years that followed, petroleum com panies moved even farther into the ocean. In 1947, a cons ortium of oil com panies built the first platform that you couldn't see from land

in the Gulf of Mexico. Even the North Sea, which endures nearly constant inclement weather, is currently home to many offshore drilling sites [sou rce: The Guardian].

Today's oil rigs are truly gigantic structures. Some are basically floating cities, emp loying and housing hundreds of people. Other massive production facilities sit atop undersea

towers that descend as far as 4,000 feet (1,219 meters) into the depths -- taller than the world's mos t ambitious s kyscrapers. In an effort to sus tain their fossil fuel dependency,

humans have built some of the largest floating structures on Earth.

In this article, we'll examine how petroleum companies go about sn iffing out this buried, black gold and the methods they use to extract it.

Hunting for Fossil Fuels

While fossil fuels have only become the driving force behind human civilization in the last couple of centuries, oil and natural gas

have been making their way back to the Earth's surface for millions of years. Spanish conquistadors observed oil rising to the

surface in the Gulf of Mexico in the 16th century, and the Chinese drilled for it in the ground as ea rly as 347 A.D. [source: Totten]. To

find even older evidence, you don't have to look any farther than the prehistoric anim als unlucky enough to have been consum ed by

the world's tar pits.

However, mos t of the world's petroleum is trapped between 500 and 25,000 feet (152 and 7 ,620 meters) unde r dirt and rock. All of

this oil began as tiny plants and animals called plankton, which died in the ancient seas between 10 and 600 m illion years ago.

This decaying matter drifted to the bottom of the ocean and, over time, was covered with sand and mud. In this oxygen-free

environment, a kind of slow cooking process took place. Millions o f years of heat and pres sure eventually transformed this organic

material into vast depos its of liquid, gas and solid pe troleum, all capped in traps under thick layers of rock. We call liquid

petroleum oiland gaseous petroleum natural gas. Solid petroleum depos its often take the form of oil shale or tar sands.

Needless to say, these foss il fuel deposi ts don't just start bubbling crude every time a hillbil ly fires a rifle. Geologists s tudy surface

features and satellite maps , check soil and rock sam ples, and even use a device called a gravity meter to find sub tle gravitational



Dr. Marli Miller/Visuals Unlimited/Getty

Images

Petroleum rises naturally to thesurface at this tar seep in central

California.

Drilling Rights

Once oil companies have identified a possibleundersea oil depos it, they have to obtain drillingrights. Most of the coas t and ocean be long tostates or nations, so companies have to leasedesired areas from the res pective government.For more information about this iss ue, read Whoowns the oceans?

Don Klumpp/Iconica/Getty Images

Drill ships like this one are oftenused to drill exploratory wells into

suspected petroleum deposits.

Note the drill pipe segments storedon deck.

fluctuations that m ight indicate a s ubterranean flow of oi l. Not all of these options a re particularly viable, however, if the terrain

you're canvassing is thousands of feet below pitching ocean waves.

When searching for fossil fuels at sea, oil geologists are able to use special sniffer equipment to detect traces of natural gas in

seawater. But as this method can only help find seeping depos its, oil companies large ly depend on two other means of locating

traps.

When close to the s urface, certain rocks affect the Earth's normal magnetic field. By using sens itive magnetic survey equipment, a

ship can pas s over an area and map any magnetic anomali es that occur. These readings allow geologis ts to hunt for the telltale

signs of underground traps.

Surveyors can also detect poss ible traps through the us e of seismic surveying. This method, known as sparking, involves

sending shock waves down through the water and into the ocean floor. Sound travels a t different speeds through d ifferent types of

rock. If the shock wave reaches a change in rock layers, it bounces back up toward hydrophones dragged behi nd the survey ship.

With the aid of computers, sei smo logists can then analyze the information to pinpoint pos sible traps in the Earth.

Survey ships use bo th compressed air guns and explosives to emit

shock waves. Of these two methods , air guns are far les s of a threat to

sea life, but even acoustic pollution poses a threat to such s eismically

aware sea animals as the endangered blue whale.

What happens once s urvey teams detect undersea oil deposits? Well, it's

time to mark down the GPS coordinates, plant a buoy and obtain a

government lease to begin a l ittle exploratory drilling and see what you've

got.

Exploratory Drilling

You can s end s hock waves

down to the ocean floor all

day, but ultimately you're

going to have to drill a little

if you want to know if you

have a potential gusher onyour hands . To handle this

job, oil companies send out

a mobile drill ing platform to

perform exploratory drilling

on a site. Some of these

platforms are ship-based,

but others have to be towed

to the drilling s ite by other

seagoing vessels.

An exploratory drilling rig

will typically drill four

temporary exploratory

wells over a suspected

deposi t, each taking 60 to

90 days to complete.

Geologists in itially drill to

obtain a core sample. Theprinciple is the same as if

you s tuck a hollow cylinder into a birthday cake and then removed it. You'd then be able to examine the cylinder to dis cover what varying layers of icing and cake existed inside

the cake. Will there be ice cream? This is one m ethod of finding out without cutting yourself a whole slice.

Of course, oil geologis ts aren't hoping for ice cream. They're looking for signs of petroleum , which they call a show. Once a show has occurred, drilling stops and geolog ists

perform additional tests to make s ure oil quality and quantity are su fficient to justify further action. If so, they then drill additional wells to subs tantiate the findings.

Once geologists have established the worth of a petroleum deposit, it's time to drill a production well and begin harvesting the riches. An average well lasts a good 10 to 20

years before it's no longer profitable, so offshore production platforms are built with a long stay in mind. The pla tforms are typically fixed directly to the ocean floor us ing either

metal and concrete foundations or tethering cables . As you might imagine, the platform has to remain as s tationary as pos sible during all this drill ing, no matter how severe the

weather becomes.

One platform can boast as many as 80 wells , though not all of them go straight down. Directional drilling allows oi l platforms to sink production wells into the ocean floor at an

angle in orde r to reach deposits m iles away from the drill s ite. If you've seen the 2007 film "There Will Be Blood," then you may know this as the "I drink your milkshake!" method.

In the film, a maniacal, mus tached oilman boas ts that, through directional drilling, he's managed to drain all the oil beneath a nearby parcel of land. This is sue als o arises in

the offshore drilling industry. For ins tance, in California, the state is au thorized to drill new wells if it can prove that wells in adjacent federal waters are draining Ca lifornia-owned

oil deposits.

Even after its wells have run dry, offshore production platforms o ften find renewed life as a central hub for other nearby oil platforms. The other platforms pipe petroleum over for

processing and/or storage.

So you've sunk millions into erecting your oil rig. Now it's time to get busy drinking that offshore m ilkshake.

Undersea Drilling

You've established your multimillion -dollar offshore drilling platform and, miles beneath you, there's a fortune in untapped petroleum deposits. The challenge in unders ea

drilling is transferring all that precious oil and gas from po int A to point B without losing it and polluting the ocean. How do you tunnel into the Earth without water flowing into the

hole or all the oil surging up in to the sea?

To ensure accurate drilling, engineers connect the drill site to the platform with a subsea drilling template. On a very basic level, this serves the same purpos e as the templa tes

you m ight have used to trace a pattern or carve a jack-o-lantern design into a pumpkin. While the design may vary depending on the exact ocean floor conditions, the drilling

template basically resembles a large me tal box with holes in it to mark the site of each production well.

Since production wells often have to sink m iles into the Earth's crust, the drill itself consis ts mos tly of multiple 30-foot (9.1-meter) drill pipes s crewed together, called a drill

string. They're much like tent poles in this res pect. A turntable on the platform rotates the drill s tring and, at the other end, a drill bi t grinds through the Earth. The drill bit

generally consists of either a rotating bit embedded with industrial diam onds o r a trio of rotating, interlocking bits with steel teeth. In the weeks or m onths it takes to reach the oil

deposi t, the bit may dull and require replacem ent. Between the platform and the ocean floor, all of this equipm ent descends through a flexible tube called a marine riser .



Arnulf Husmo/Stone/Getty Images

An enormous offshore platform lights up the night off the coast of Norway.

Terje Rakke/Riser/Getty Images

Offshore drilling platforms burn off excess natural gas, giving themtheir signature flares.

A Slippery Subject

Despite our culture's dependence on petroleum,

not everyone's a huge fan of offshore oil drilling.Criticism ranges from dire environmentalwarnings to concerns over how oil rigs obstructthe view on a holiday beach trip. To learn more,read Why is offshore d rilling s o controversial?

Malcolm File/Photodisc/Getty Images

A jack-up rig can raise and lower itself on three or four massive"legs." Oil companies float these structures out to a drill site and thenlower the legs until they touch the sea floor and elevate the rig out of

the water.

As the boring hole des cends deepe r into the ground, operators send a constant flow of drilling mud down to the drill b it, which then flows back up to the platform. This thick,

viscous fluid consists of clay, water, barite and a m ixture of special chem icals. The drilling mud lubricates the drill bit, seals the wall of the well and controls press ure inside the

well. Also, as the drill b it shreds rock, the resulting fragments become s uspended in the mud and leave the well in the rising, return flow. On the surface, a circulation system

filters the mud before sending it back down the well.

The drilling mud acts as the first line of defense against high, sub terranean press ures, but there's still a high ris k of a blowout of fluid from the well. To handle these events,

petroleum companies install a blowout prevention system (BOP) on the s eafloor. If

press urized oil and gas gush up the well , the BOP will seal the well with hydraulic valves and

rams . It will then reroute the surging well fluids into specially designed containment systems.

The drilling process itse lf occurs in phas es. The initial surface hole, with a diameter of about

18 inches (46 centimeters) des cends from s everal hundred to several thousand feet. At this

point, engineers remove the drill string and send down hollow segments of metal pipe called

casing. Once cemented into p lace, this conductor pipe barrier lines the ho le and prevents

leaks and caving. For the next phase, a 12-inch (30-centimeter) drill bit digs the well even

deeper. Then, the drill string is agai n removed so surface casing can be ins talled. Finally, an

8-inch (20-centimeter) bit bores the rest of the way to the petroleum deposi t. This final stretch

is called the bottom hole, and is lined with intermediate casing. Throughout this proces s, a

device called a packer travels down the well, expanding against the walls to ens ure

everything is s ealed.

In the next section, we'll follow the well down to the petroleum itself.Striking Oil

Once the drill hits petroleum, a final bit of casing called a production casing goes down to the

bottom of the shaft. This section of casing term inates in a s olid cap, closing the well off from

the surrounding petroleum reservoir . It may seem a bit odd to s eal up the p rize once you've

finally reached it, but the goal is n't to jus t vent press urized oil and gas up to the surface, but to

control its flow. Engineers s end down explosives to perforate the production casing at

different depths to allow petroleum into the well. This all ows the oil and gas to reach the

surface under less pressure, and not as a blasting geyser.

Initially, the natural pressure from the s ubsurface petroleum res ervoir is s ufficient to pushfluids and gas to the surface. Eventually, however, this p ressu re declines , and the use of a

pump o r injections of gas, oil or water are required to bring the petroleum to the s urface. By

adding water or gas to the reservoir, engineers are able to increase rese rvoir press ure,

causing the petroleum to rise again. In some cases, compressed air or steam is sent down a

well to heat the remaining petroleum, which also increases pressure.

If what came up from the wells was pure petroleum, it would just be a m atter of barreling it up

at this point. But this isn't usuall y the case, and it's why offshore drilling platforms often boas t

full production facilities as well. The liquid that rises up to the platform is a mixture of crude

oil, natural gas, water and sedim ents. Most oil refinement takes place onshore, but oil

companies som etimes us e converted tanker ships to treat and store oil at sea. This process

removes unwanted subs tances from the oil, prior to refining.

Natural gas falls into two categories: wet and dry. Wet natural gas contains various vaporized liquids, and thes e have

to be filtered out before it can be transported elsewhere. Dry natural gas, on the other hand, is free of these pollutants.

At this poin t, undersea p ipelines and oil tankers transport the separated oil and natural gas to onshore storage and

treatment plants.

Eventually, a well will either run dry, or the costs of further development will outweigh potential future profits. When this

happens , petroleum com panies p lug and abandon the well. At this point, operators remove platforms from their

moorings -- with explosives if need be -- and either relocate them or drag them back to shore for scrap. Divers then cut

the well casing off below the surface of the ocean floor and seal it in with concrete. In some cases, however, portions of

the oil rig remain and are s lowly overtaken by sea life.

In the next section, we'll take a look at the various kinds of oil platforms in use today.

Mobile Drilling Platforms

During the exploratory drilling phas e, the goals are s imple: Get in, find out if there's oil and

then move on to the next site. If a location proves prospe rous, then the company can bring in a

more perm anent structure. But for the months it takes a crew to size up a location, a mobile

drilling platform provides everything a team needs with minim al investment. Jack-ups, the

mos t common rigs , typically cost between $180 milli on and $190 m illion to build [source:

Offshore Magazine]. There are five varieties of mobile drilling platforms.

Drilling barge: Mostly used for shallow drilling in non-ocean waters, thise pla tform is exactly

what it sounds li ke: a floating barge with drilling equipment. Tugboats tow the platform out tothe site, where anchors hold it in place. However, given that drilling barges bas ically just float

on the s urface, they're only suitable for calm waters.

Jack-up: This rig resem bles a d rilling barge, but with one exception. Once this platform

reaches the drilli ng site, it can lower three or four mas sive legs in to the water until they touch

the bottom. At this poin t, they lift the platform out of the water. This provides a much m ore

stable environment from which to drill, as the legs stabilize the platform against winds and lift

it above pitching waves. The des ign has its limits, however, as deeper waters requ ire

impractically large legs.

Submersible rig: This drilling pl atform combines s ome of the properties of drilling barges

and jack-ups. Only in this case, the production facilities a re elevated on stilts hund reds of feet

above pontoonlike barges . After reaching the drill s ite, the crew floods the barges with water.

The barges s ink until they rest on the sea o r lake floor, while the platform rem ains el evated

above the water on stilts. In effect, the crew s inks the rig in to order to anchor it. When the time comes for the rig to relocate, the crew pum ps the wa ter back out of the barges,

causing them to float back up to the surface and pus h the stilted platform back up into the air. Like the jack-up, this platform is lim ited to shallow waters.



Offshore drilling platforms

Getty Im ages/Handout/Getty Images News/Getty Images

A spar production platform floats at sunset in the Gulf of Mexico. Thestructure's massive cylindrical hull extends down into the depths for

hundreds of feet.

Hellish Heat and Chilling Depths

Deep-sea waters reach nearly freezingtemperatures, contain pressures great enough tocrack iron casings and are subj ect to rough,deep-sea currents. Engineers have to designequipment that can stand up to the pressure,while also preventing boiling oil from hot,underground dep ths from cooling to a solid formand rupturing pipes when it emerges into thechilly ocean environment. While antifreeze hasplayed an important part in preventing this thusfar, more advanced methods are under development [source: Wired].

Semisubmersible rig: This platform is m uch like a submersible rig, except it's des igned to work in much deeper waters. Instead of sinking until its lower hull rests on the

seafloor (which, in deeper waters, would drown everyone), it simply lets enough water in to lower it to appropriate operating heigh ts. The weight of the lower hull s imply

stabilizes the drilling platform, while massi ve anchors hold it in place.

Drill ships: This is es sentially an oceangoing vessel with, you gues sed it, a drilling platform in the m iddle. The drill string extends down to the ocean floor through a moon hole.

Drill ships ope rate in very deep water and often have to ride out rough sea cond itions. They use dynamic positioning equipment to keep aligned with the drill si te. This

equipment uses s atellite information and senso rs on the subs ea drilling templa te to keep track of the drilling location. Using this data, electric motors on the underside of the

hull cons tantly move the ship to keep it lined up with the well.

When it's time for these temporary platforms to move on, the really big rigs en ter the picture. On the next page, we'll take a look at the d ifferent types of offshore production

platforms.

Offshore Production Platforms

Once the exploratory drilling phas e is over and geolog ists have determined that a petroleum res ervoir is worth the mas sive expense, oil com panies prepare to establis h an

offshore production platform. These rigs are des igned to last decades , often far from landand in som e of the most hostile waters on Earth.

Construction crews typically build the platforms on a nearby coast and then trans port them as needed to the drilli ng site. Production costs for these vessels typically run in the

hundreds of millions of dollars . There are currently seven di fferent varieties of offshore

platforms.

Fixed platform: This platform design tackles the challenges of offshore drilling in the m ost straightforward and indus trial way imaginable. Need to fix production facilities to a

position above your drilling site? Why not construct a gigantic tower of concrete and steel and mount your oil rig on top? To fully comprehend the amount of materials that go into

constructing this underwater structure, consider that they operate at depths o f 1,500 feet (457 meters) or l ess -- that's jus t a little taller than Chicago's Sears Tower. These

platforms are extremely stable, des pite the fact that the concrete bas e is n't even attached to the s eafloor. It simply stays in place due to al l the weight above it. However, at

depths greater than 1,500 feet, the design begins to become m ore impractical due to material

costs.

Compliant tower : These rigs take the basic idea of the fixed platform and m ake it viable to operate in depths of 1,500 feet to 3,000 feet (457 meters to 914 m eters). The design

achieves this by relying on a narrower tower of steel and concrete. But while fixed platform des igns are rigid, compliant towers are des igned to sway and move with the stresses

of wind and sea -- even hurricanes. In this res pect, they're much like m odern skyscrapers that

are built to sway with the wind.

Sea Star platform: The Sea Star platform is bas ically a larger version o f the semis ubmers ible des ign we talked about in the las t section. The production facilities sit atop a

large submers ible hull on a tower. When the lower hull fills wi th water, it sinks to a lower

depth, providing s tability while keeping the facilities h igh and dry. However, instead of gian t

anchors hold ing it in place, the Sea Star is connected to the ocean floor by tension legs.

These long, hollow tubes rem ain rigid at all times, preventing any up-and-down motion on the

platform. The legs are just flexible enough to allow s ide-to-side motion, which helps absorb

the stress of waves and wind. These platforms operate from depths of 500 to 3,500 feet (152

to 1,067 meters) and are typically used to tap sm aller reservoirs in deep waters.

Skip to the next page to learn about the four remain ing types of offshore production platforms.More Offshore Production Platforms

In the last section, we looked at some of the varieties of offshore production pla tforms that

allow petroleum companies to reach drill sites as deep as 3,500 feet (1,067 meters). But

there's a great deal of oil under the world's oceans, and more than a few methods of reaching

it. Some of these des igns do away with the traditional concept of an oil platform altogether,

while others elevate some of the designs from the las t section to even grander proportions.

Floating production system: These platforms can take the form of either floatingsemisubmersible platforms or drill ships. The basic idea behind their design is that, once the

well has been drilled, much of the production equipm ent can be mounted on the seafloor and

the petroleum pum ped to the surface facilities through flexible risers. Meanwhile, the p latform

or ship s tays in pos ition with anchors or a dynamic pos itioning system. This approach allows

oil compan ies to reach depths o f up to 6,000 feet (1,829 meters).

Tension leg platform: This platform is ess entially a king-sized version o f the Sea Star

platform, except the tension legs extend from the ocean floor to the platform itself. It

experiences more horizontal motion and a certain degree of vertical motion, but it allows oil

companies to drill at depths of up to 7,000 feet (2,134 meters), well over a mile (1.6

kilometers) beneath the waves.

Subsea system: This approach takes the idea of mounting the wellhead on the sea floor and

applies it to even greater depths -- 7,000 feet (2,1334 meters) or m ore. Once the well has

been drilled by a surface platform, the automated systems transfer the oil and natural gas to

production facilities by either risers or undersea pi pelines .

Spar platform: Finally, if you abs olutely need to drill a hole at a depth of 10,000 feet (3,048 me ters), then the spar

platform is the oi l rig for you. With this des ign, the drilling pla tform s its atop a gian t, hollow cylindrical hull. The other

end of the cylinder des cends around 700 feet (213 meters) into the ocean depths. While the cylinder stops far above

the ocean floor, its weight stabilizes the platform. A network of taunt cables and lines trail out from the cylinder to secure

it to the ocean floor in what is called a lateral catenary system. The drill string descends down through the length of

the cylinder's interior and down to the ocean floor.

As technology improves and existing petroleum res erves wane, exploration will continue to dive into the s ubterranean

depths. This combination of deeper waters and deeper oil wells will pose even greater challenges for oil companies.

While technology plays a vital role in offshore drilling, these mas sive constructions a re also home to large crews of

workers. In the next section, we'll take a look at life on an oil rig.

Oil Rigs: Cities on the Sea

Offshore production platforms may be marvels of modern engineering , but none of that valuable petroleum makes its

way out of the wells and into

refineries without a great deal of human labor. In fact, larger oil rigs often employ more than a hundred workers to keep

the platform running. As many of these rigs are located far from cities and shores , the employees (who range from



Justin Guariglia/National Geographic/Getty Images

A remote access technician dangles underneath a North Atlantic oil rigto inspect the structure's underbelly.

engineers and geologists to divers

and doctors) live for weeks at a time

on these huge structures.

There are definitely pros and cons to

working on an offshore platform. On

the plus s ide, salary and benefits

are us ually pretty good, and

employees typically enjoy long rest

periods when they're not at sea.

Employees will work one or two

weeks on the oil rig, then spend one

or two weeks at home. The

downside , however, is that when

they're at sea, they work 12-hour days, seven days a week. The

weeks away from hom e can strain

workers' home li ves, as they spend

half the year away from their family.

To help cope with these is sues , petroleum compani es frequently put a great deal of effort into providing comfortable living conditions for offshore workers. In many cases,

quarters are on par with those found on major cruise s hips -- featuring private rooms, satellite TV and even gym, sauna and recreation facilities. The food onboard also tends to

be above average -- and available 24 hours a day. After all, work on an oil rig continues day and nigh t, with employees working rotating schedu les of daytime and nighttime

shifts. Helicopters and sh ips bring in mos t of the necess ary materials for day-to-day life on an oil rig, often through choppy weather conditions.

Oil rigs aren't all Jacuzzis and cafeterias, though. Outside the living quarters, life on an oil rig is a constant encounter with potentially deadly conditions. The bus iness of an oil rig

boils down to drawing extremely flammable fluids out of the Earth, burning s ome o f it off in a giant jet of flame and separating highly poisonous hydrogen sulfide gas from the

extracted petroleum. On top of this, workers have to deal with all the typical dangers associated with operating dangerous m achinery and working at tall heights in windy, stormy

conditions.

To cope with these d angers, petroleum companies m ake use of extensive training programs on how to work safely with volatile subs tances on the high seas . These m easures

not only help to safeguard the lives of their em ployees, but also protect their truly mas sive financial investment in constructing and s ustaining an offshore production platform.

Explore the links on the next page to learn more about oil and the bus iness of petroleum.

Lots More Information

Related HowStuffWorks Articles

Oil Shale Quiz

How Oil Drilling Works

How Oil Refining Works

How Gas Prices Work

How Gasoline Works

What is the worst environmen tal disas ter in history?

Why is offshore drill ing so controversial?

What's oil shale?

Have we reached peak oil?

How do you clean up an oil s pill?

More Great LinksAmerican Petroleum Institute

Schlumberger Oilfield Glossary

World Petroleum Council

Sources

Coile, Zachery. "McCain calls for more offshore drilling." San Francisco Chronicle. June 17, 2008. (Sept. 2, 2008)

http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2008/06/17/

MNR111A4M8.DTL&type=politics

Freudenrich, Craig. "How Oil Drilling Works. " HowStuffWorks.com. April 12, 2001. (Sept. 2, 2008)

http://science.howstuffworks.com/oil-drilling.

Hale, Briony. "The ups and downs of life offshore." BBC News. June 18, 2002. (Sept. 2, 2008)

http://news.bbc.co.uk/2/hi/business/2041404.stm

"Happy Landings." The BP Magazine. 2008. (Sept. 2, 2008)

http://www.bp.com/sectiongenericarticle.do?categoryId=

9023145&contentId=7043392Holing, Dwight. "Coastal Alert." Island Press. 1990.

"Jackup building price surges on strong demand." Offshore Magazine. March 12, 2007. (Sept. 5, 2008)

http://www.offshore-mag.com/display_article/286837/120/ARTCL/none/VESSL/

Jackup-building-price-surges-on-strong-demand/

Kelly, David. "Oil Rig, 9 Miles Offshore, Is Home and Work Above the Sea." Los Angeles Times. May 27, 2001. (Sept. 2, 2008)

http://articles.latimes.com/2001/may/27/local/me-3292

Little, Amanda Griscom. "Pumped Up: Chevron Drills Down 30,000 Feet to Tap Oil-Rich Gulf of Mexico." Wired. Aug. 21, 2007. (Sept. 2, 2008)

http://www.wired.com/print/cars/energy/magazine/15-09/mf_jackrig

Macalister, Terry. "More than half of North Sea oil rigs fail safety checks." Nov. 22, 2007. (Aug. 28, 2008)

http://www.guardian.co.uk/business/2007/nov/22/oil

"Norwegian Billionaires' Oil-Rig Building Spree Raises Glut Risk." Bloomberg News. Oct . 11, 2005. (Sept. 5, 2008)

http://www.bloomberg.com/apps/news?pid=nifea&&sid=a0Vcxph3Y2ZU

"Offshore Drilling." NaturalGas.org. 2004. (Sept. 2, 2008)

http://www.naturalgas.org/naturalgas/extraction_offshore.asp

"Offshore Drilling." World Petroleum Council. March 13, 2003. (Sept. 2, 2008)



http://www.world-petroleum.org/education/offdrill/index.html

"Petroleum production." Britannica Online Encyclopædia. 2008. (Sept. 2, 2008)

http://www.britannica.com/EBchecked/topic/1357080/petroleum-production

"Petroleum Technologies Timeline." National Academy of Engineering. 2008. (Sept. 2, 2008)

http://www.greatachievements.org/?id=3675

"Rank Order - oil - consumption." CIA World Fact Book. Aug. 21, 2008. (Aug. 27, 2008)

https://www.cia.gov/library/publications/the-world-factbook/rankorder/2174rank.html

Schlumberger Oilfield Glossary. 2008. (Sept. 2, 2008)

http://www.glossary.oilfield.slb.com/default.cfm

"Spar Platform." GlobalSecurity.org. Nov. 11, 2006. (Sept. 2, 2008)

http://www.globalsecurity.org/military/systems/ship/platform-spar.htm

Totten, George E. "A Timeline of Highlights From the Histories of ASTM Committee DO2 and the Petroleum Industry." ASTM International. 2007 (Sept.

4, 2008)

http://www.astm.org/COMMIT/D02/to1899_index.html

"World's Ten Tallest Buildings." SkySc raperPage.com. 2008. (Sept. 2, 2008)

http://skyscraperpage.com/diagrams/?1241105

hsw - offshore drilling

Documents