Spiga

SPE Updates

How Do 4-D and 4-C Seismic Work?

Used to find oil and gas prospects, there are multiple types of seismic surveys that can be produced over reservoirs to understand the subsurface environment. Made up of reflection and refraction mapping, seismic surveys give geologists a better idea of what lies beneath the surface - or even below thousands of feet of water.

4-D Seismic

One of the most intricate forms of seismic survey, 4-D (four-dimensional) seismic, is a type of geophysics. Also known as time lapse seismic, 4-D seismic incorporates numerous 3-D seismic surveys over the same reservoir at specified intervals of time. Studying multiple time-lapsed 3-D surveys, or three-dimensional subsurface images, portrays the changes in the reservoir over time.

Four-D seismic can determine changes in flow, temperature, pressure and saturation. By scanning a reservoir over a given period of time, the flow of the hydrocarbons within can be traced and better understood. For example, as hydrocarbons are depleted from a field, the pressure and composition of the fluids may change. Additionally, geologists are interested in understanding how the reservoir reacts to gas injection or water flooding. Furthermore, 4-D seismic can help to locate untapped pockets of oil or gas within the reservoir.

Typically, 4-D seismic data is processed by subtracting the data from one survey from the data of another. The amount of change in the reservoir is defined by the difference between the two. If no change has occurred over the time period, the result will be zero.

4-C Seismic

In addition to 4-D seismic, 4-C seismic encompasses multi-component seismic exploration, outlining both compressional and shear waves given off by a seismic source.

While a compressional wave, also known as a P-wave, is how sound travels through the air, where particles travel closer and then farther apart; a shear wave, or S-wave, is similar to an ocean wave, where the particles actually move up and down.

P-waves travel at a higher rate of speed, and unlike S-waves, P-waves are able to pass through liquids and gases. While compressional waves are distorted by gas in the reservoir, shear waves are not affected, making shear waves a better measurement to determine gases in the sedimentary rocks.

Four-C seismic is used to pinpoint and determine the locations of subsurface fractures, as well as define the make-up of the sedimentary rock layers and their corresponding fluids.


Read more!

How does EOR work?

Oil production is separated into three phases: primary, secondary and tertiary, which is also known as Enhanced Oil Recovery (EOR). Primary oil recovery is limited to hydrocarbons that naturally rise to the surface, or those that use artificial lift devices, such as pump jacks. Secondary recovery employs water and gas injection, displacing the oil and driving it to the surface. According to the US Department of Energy, utilizing these two methods of production can leave up to 75% of the oil in the well.

The way to further increase oil production is through the tertiary recovery method or EOR. Although more expensive to employ on a field, EOR can increase production from a well to up to 75% recovery.

Used in fields that exhibit heavy oil, poor permeability and irregular faultlines, EOR entails changing the actual properties of the hydrocarbons, which further distinguishes this phase of recovery from the secondary recovery method. While waterflooding and gas injection during the secondary recovery method are used to push the oil through the well, EOR applies steam or gas to change the makeup of the reservoir.

Whether it is used after both primary and secondary recovery have been exhausted or at the initial stage of production, EOR restores formation pressure and enhances oil displacement in the reservoir.

There are three main types of EOR, including chemical flooding, gas injection and thermal recovery. Increasing the cost of development alongside the hydrocarbons brought to the surface, producers do not use EOR on all wells and reservoirs. The economics of the development equation must make sense. Therefore, each field must be heavily evaluated to determine which type of EOR will work best on the reservoir. This is done through reservoir characterization, screening, scoping, and reservoir modeling and simulation.

Thermal Recovery

Thermal recovery introduces heat to the reservoir to reduce the viscosity of the oil. Many times, steam is applied to the reservoir, thinning the oil and enhancing its ability to flow. First applied in Venezuela in the 1960s, thermal recovery now accounts for more than 50% of applied EOR in the US.

Chemical Injection

Chemical injection EOR helps to free trapped oil within the reservoir. This method introduces long-chained molecules called polymers into the reservoir to increase the efficiency of waterflooding or to boost the effectiveness of surfactants, which are cleansers that help lower surface tension that inhibits the flow of oil through the reservoir. Less than 1% of all EOR methods presently utilized in the US consist of chemical injections.

Gas Injection

Gas injection used as a tertiary method of recovery involves injecting natural gas, nitrogen or carbon dioxide into the reservoir. The gases can either expand and push gases through the reservoir, or mix with or dissolve within the oil, decreasing viscosity and increasing flow.

Carbon dioxide EOR (CO2-EOR) is the method that is gaining the most popularity. While initial CO2-EOR developments used naturally occurring carbon dioxide deposits, technologies have been developed to inject CO2 created as byproducts from industrial purposes.

First employed in the US in the early 1970s in Texas, CO2-EOR is successfully used in Texas and New Mexico and is expected to become more widely spread in the future. Nearly half of the EOR employed in the US is a form of gas injection.

Other EOR applications gaining acceptance are low-salinity water flooding, which is expected to increase production by nearly 20%, and well stimulation, which is a relatively low-cost solution because it can be employed to single wells (rather than the whole reservoir).

Offshore EOR Applications

Although EOR applications are predominantly employed onshore, technologies are being developed to expand the reach of EOR to offshore applications. Challenges that presently exist for offshore EOR include economics of the development; the weight, space and power limitations of retrofitting existing offshore facilities; and fewer wells that are more widely spaced contributing to displacement, sweep and lag time.

Currently, the application of EOR is being considered for a number of offshore developments. With successful subsea processing and secondary recovery methods employed in offshore environments through water and gas injection, the technologies to apply EOR methods is quickly nearing.

EOR in the US

The US Department of Energy estimates that currently there are 89 billion barrels of additional oil trapped in onshore reservoirs. This is in great contrast to the country's current domestic proven reserves, which is estimated at 21.9 billion barrels. The DOE stresses that much of this production could be tapped by implementing EOR methods, namely the injection of carbon dioxide.

In fact, the governmental agency claims that the pervasive application of EOR technologies on US reserves could increase the country's oil recovery from approximately 30% to more than 60%. If this oil was added to the US proven reserves, the country would rank fifth in the world for the size of its reserves.

If this oil could be recovered, the country's dependence on foreign oil would be greatly depreciated, an effort for which the US has been striving. However, a wider application of EOR methods on US reservoirs requires a much higher cost of production, and the price of oil must legitimize the investment.

By Phaedra Friend
of Rigzone.com

Read more!

Great opportunity to make a difference!

Right now any gift you make to The Fresh Air Fund will be matched dollar for dollar by a group of generous donors! If you can give $25 that means $50 for inner-city children. $50 becomes $100!
But you must make your donation by June 30th to take advantage of this wonderful opportunity!Donate now!



If you have been reading novel inspiration regularly you must be aware of The Fresh Air Fund. These guys are serving children since 1877. For further information about this noble cause please read my earlier post here.

So what are you waiting for? Take my word and Donate now!

Read more!

How drillships work?

Truly what it sounds like, a drillship is a marine vessel that's been modified to drill oil and gas wells. While drillships look similar to a tanker or cargo vessel, there are a couple of major differences. Drillships are equipped with a drilling derrick and moon pool. Additionally, drillships have extensive mooring or positioning equipment, as well as a helipad to receive supplies and transport staff.

Typically employed in deep and ultra-deep waters, drillships work in water depths ranging from 2,000 to more than 10,000 feet (610 to 3,048 meters). Drilling equipment is passed through the vessel's moon pool and connected to the well equipment below via riser pipe, a somewhat flexible pipe that extends from the top of the subsea well to the bottom of the drillship.

Drillships are differentiated from other offshore drilling units by their easy mobility. While semisubmersible rigs can also drill in deep waters, drillships are able to propel themselves from well to well and location to location, unlike semisubs, which must rely on an outside transport vessel to transfer them from place to place.

While capable of drilling in deep and ultra-deep waters, a disadvantage to using a drillship is its susceptibility to being agitated by waves, wind and currents. This is especially troublesome when the vessel is actually drilling, because the drillship is connected to equipment thousands of feet under the sea.

A proper mooring system on a drillship is integral to drilling successful wells. In shallower waters, drillships are moored to the seafloor with anywhere from 6 to twelve anchors. Once the water depth becomes too deep, drillships depend on dynamic positioning systems (DPS) to keep the vessel in place while drilling. DPS relies on several thrusters located on the fore, aft and mid sections of the ship, which are activated by an onboard computer that constantly monitors winds and waves to adjust the thrusters to compensate for these changes. Sometimes, both positioning systems are used.

Drillships were first developed in the late 1940s by marine architects. Created to overcome water depth challenges offshore California in the Pacific Ocean, the first drillship was a surplus U.S. Navy patrol craft that was equipped with cantilevered drilling equipment. Seeing some success, the next drill ship incorporated a moon pool and an onboard drilling derrick. After its success, companies soon ordered the construction of subsequent drillships.

Transocean, Pride, Seadrill, Frontier Drilling and Noble are a few of the companies that own and operate drillships globally.

Written by Leslie Fiedler for Rigzone.com

Read more!

Halliburton to Launch Next Gen Stimulation Vessel Offshore West Africa

Halliburton's Completion and Production Division is launching a next generation stimulation vessel, the Stim Star Angola, in response to operators' needs for stimulation treatments on offshore West Africa assets. The new vessel will serve as a high performance platform for delivering technology and helping reduce rig downtime and associated costs for operators.

"We are committed to meeting the needs of operators in the Offshore Angola Region, one of the premier deepwater basins on the globe," said Marc Edwards, vice president of Production Enhancement, within Halliburton's Completion and Production Division.

"With the new Stim Star Angola stimulation vessel, operators will have cost-effective access to all phases of production stimulation including acidizing, fracturing, sand control and conformance solutions for this developing deepwater market."

The new vessel was designed to help minimize rig downtime. Certified for DP2 dynamic positioning, the Stim Star Angola will be capable of working in difficult sea conditions in deepwater locations at tension leg platforms, drill ships, large semisubmersibles, or single wellheads. Cycle time will be minimized by the vessel's proppant, acid and liquid additives capacity, which permits loading sufficient material for multiple treatments, reducing trips to the dock. Cycle time will also be reduced by using the vessel's onboard crane and water maker system.

The vessel is uniquely capable of delivering specialized fracturing and acidizing treatments supported by the latest Halliburton technology developments, including for example, the patented SurgiFrac® service for fracturing deviated and horizontal wellbores.

In keeping with Halliburton's commitment to outstanding health, safety and environmental performance, the Stim Star Angola is engineered to meet or exceed all regulatory requirements enabling the vessel to operate in any international location. The Stim Star Angola will be available by the third quarter of 2009 and will be based in Soyo, Angola.


Read more!

Top graduate schools for petroleum engineering in USA

Following is the list of Top 10 Petroleum Engineering Schools (Graduate Programs) in the USA in 2009.

Rank, University Name, Location, Score

1 University of Texas--Austin (Cockrell), Austin, TX 4.6

2 Stanford University, Stanford, CA 4.2

2 Texas A&M University--College Station (Look), College Station, TX 4.2

4 University of Tulsa, Tulsa, OK 4.0

5 Colorado School of Mines, Golden, CO 3.4

5 Pennsylvania State University--University Park, University Park, PA 3.4

5 University of Oklahoma, Norman, OK 3.4

8 Louisiana State University--Baton Rouge, Baton Rouge, LA 3.3

9 University of Southern California (Viterbi), Los Angeles, CA 3.1

10 New Mexico Institute of Mining and Technology, Socorro, NM 2.8

10 Texas Tech University, Lubbock, TX 2.8

Source: U.S. News and World Report’s 2009 Best Graduate Schools

Read more!

ExxonMobil Barrels in $4.6B in First Quarter 09

"ExxonMobil posted solid first quarter results despite the slowdown in the global marketplace and sharply lower commodity prices. ExxonMobil's first quarter earnings were $4.6 billion, down 58% from the first quarter of last year. Earnings per share were down 54% reflecting lower earnings and the benefit of the share purchase program," said ExxonMobil's Chairman, Rex W. Tillerson.

"In spite of the dramatic changes to the global economic environment, ExxonMobil is maintaining its long-term focus and disciplined approach to capital investment. In the first quarter, capital and exploration project spending increased to $5.8 billion, up 5% from last year. We are committed to investing in our world-class inventory of projects to develop new energy supplies which are vital to economic growth," he continued.

"The Corporation returned significant cash to shareholders in the first quarter, distributing a total of $9.0 billion through dividends and share purchases to reduce shares outstanding."

FIRST QUARTER HIGHLIGHTS

  • Earnings were $4,550 million, a decrease of 58% or $6,340 million from the first quarter of 2008.
  • Earnings per share were $0.92, a decrease of 54%.
  • Capital and exploration expenditures were $5.8 billion, up 5% from the first quarter of 2008.
  • Oil-equivalent production of 4.2 million barrels per day was up slightly from the first quarter of 2008. Excluding the impacts of entitlement volumes, OPEC quota effects and divestments, production was up 2%.
  • Cash flow from operations and asset sales was approximately $9.1 billion, including asset sales of $0.1 billion.
  • Share purchases of $7.0 billion reduced shares outstanding by 1.9%.
  • ExxonMobil announced the arrival of the first Liquefied Natural Gas (LNG) cargo at the South Hook LNG receiving terminal in Wales. The terminal adds to the United Kingdom’s LNG import capacity and energy diversity, with the ability to deliver up to 2 billion cubic feet of gas daily into the U.K. market. The terminal forms part of the Qatargas II joint venture which will supply gas to the U.K. from Qatar's North Field.
  • ExxonMobil inaugurated its newest high efficiency cogeneration plant at its Antwerp refinery in Belgium. In addition to generating 125 megawatts, the new plant will reduce Belgium's carbon dioxide emissions by an amount equivalent to removing 90,000 cars from Europe's roads.
  • ExxonMobil Chemical announced it will build a technology center in Shanghai, China to provide product applications support for its growing business in the Chinese and Asian markets. The technology center is expected to be operational in 2010.

First Quarter 2009 vs. First Quarter 2008

Upstream earnings were $3,503 million, down $5,282 million from the first quarter of 2008. Lower crude oil realizations reduced earnings approximately $4.4 billion while lower natural gas prices decreased earnings about $500 million. Higher operating expenses reduced earnings about $300 million.

On an oil-equivalent basis, production was up slightly from the first quarter of 2008. Excluding the impacts of entitlement volumes, OPEC quota effects and divestments, production was up 2%.

Liquids production totaled 2,475 kbd (thousands of barrels per day), up 7 kbd from the first quarter of 2008. Excluding the impacts of entitlement volumes, OPEC quota effects and divestments, liquids production was up 3%, as increased production from projects in west Africa, the United States and the North Sea, and lower maintenance activity more than offset natural field decline.

First quarter natural gas production was 10,195 mcfd (millions of cubic feet per day), down 34 mcfd from 2008. New production volumes from project additions in Qatar, the North Sea, and Malaysia were offset by natural field decline and lower European demand.

Earnings from U.S. Upstream operations were $360 million, $1,271 million lower than the first quarter of 2008. Non-U.S. Upstream earnings were $3,143 million, down $4,011 million from last year.

Downstream earnings of $1,133 million were down $33 million from the first quarter of 2008. Volume and mix effects reduced earnings about $400 million, while unfavorable foreign exchange impacts and higher operating expenses decreased earnings about $300 million. Higher margins increased earnings about $700 million. Petroleum product sales of 6,434 kbd were 387 kbd lower than last year's first quarter, mainly reflecting asset sales and lower demand.

U.S. Downstream earnings were $352 million, down $46 million from the first quarter of 2008. Non-U.S. Downstream earnings of $781 million were $13 million higher than last year.

Chemical earnings of $350 million were $678 million lower than the first quarter of 2008. Lower volumes and lower margins each reduced earnings approximately $300 million. Unfavorable foreign exchange effects also reduced earnings. First quarter prime product sales of 5,527 kt (thousands of metric tons) were 1,051 kt lower than the prior year due to lower demand.

Corporate and financing expenses of $436 million increased by $347 million due overall to net lower interest income.

During the first quarter of 2009, Exxon Mobil Corporation purchased 107 million shares of its common stock for the treasury at a gross cost of $7.9 billion. These purchases included $7.0 billion to reduce the number of shares outstanding, with the balance used to offset shares issued in conjunction with the company's benefit plans and programs. Shares outstanding were reduced from 4,976 million at the end of the fourth quarter to 4,880 million at the end of the first quarter. Share purchases to reduce shares outstanding are currently anticipated to equal $5.0 billion through the second quarter of 2009. Purchases may be made in both the open market and through negotiated transactions, and may be increased, decreased or discontinued at any time without prior notice.


Read more!

BP Well Positioned For The Future

BP Group Chief Executive, Tony Hayward, said Thursday that the company is well positioned to face the current economic environment and to turn it into an opportunity that, going forward, will set it apart from its competition.

He added, "BP has been, and remains, an organization operating at the frontiers of the energy industry. Our technology and capability allow us to take on challenges that others cannot -- or choose not -- to confront, securing access to new resources now as in the past -- from Iran 100 years ago to the Canadian arctic Thursday.

"But operating at the frontiers is not without risks as we have tragically experienced again this month. Yesterday, I attended the very moving memorial service in Aberdeen for the victims of the helicopter crash.

"That tragedy is a sharp reminder that even Thursday, we cannot take safety for granted and our thoughts and prayers are with the families and friends of those who died.

"Over the last decade, BP has assembled an excellent portfolio of assets -- our job is to realize their full potential in the face of Thursday's uncertain environment. It is not by chance that BP has thrived for so long.

"The ingenuity of our people has led to our success -- and that gives me great confidence with which to face the future.

"A year ago, I addressed you for the first time as the CEO of BP. At the time, we faced a real competitive challenge and we needed to up our game.

"We set out a plan to deliver safe and reliable operations, to restore revenues and to reduce the complexity and cost structure of BP. We've done exactly that.

"At a corporate level, we began to reduce the complexity and cost base of our overheads. By the end of 2008, we had reduced our organization by around 3000 people, and are on track to exceed our original target of 5000 by the middle of 2009. We have also eliminated nearly 20% of the senior positions.

"2008 was a record year for BP. Replacement cost profit reached $25.6bn -- up 39% on 2007. Net cash from operating activities was $38bn, up over 50% on the previous year. Dividends paid per share rose by 30%, to 55 c/share, versus 2007.

"With our operations restored, we benefited from record high oil prices that more than compensated for the fall in the global average refining margin to $6.50 per barrel, down from almost $10 per barrel in 2007.

"Based on the past year's results, I am glad to say that BP has restored its competitive performance -- and that is no mean achievement when you think about the year that has just passed.

He added, "Over the last two years, our focus has been on realizing the full potential of our asset base. Our number one priority of safe and reliable operations has been vital to the underpinning of our restored competitive performance.

"The number of major incidents involving process safety has continued to decrease and our personal accident and injury track record continues to improve. The tragic helicopter accident in the North Sea is a graphic reminder of the inherent risks in this business -- a persistent focus on safe and reliable operations will remain our first priority.

"In E&P, we successfully grew production in line with guidance, the only one of the majors to do so. Underlying production, excluding the effects of high oil prices on our entitlements under production-sharing contracts, was up 5%.

"We started up nine major projects and made good progress on controlling costs. We achieved more than 100% reported reserve replacement for the 15th consecutive year and also delivered resource replacement of more than 200% -- a performance that puts us among the very best.

"In R&M, despite a tough environment, we made good progress in closing half of the competitive performance gap. We rebuilt full economic capability at both the Texas City and Whiting refineries, the Fuels Value Chains were fully established and we made significant progress in simplifying our marketing footprint. Our International Businesses delivered a very strong performance despite the world economic slowdown.

"Overall, we have made good progress and the operational momentum is feeding through to the bottom line.

"Set against our main competitors, we have strong financial momentum. An underlying increase in net income of 39% is well ahead of all of our competitors -- and the operational cash flow even more so. Our goal now is to maintain this momentum as we face the challenge of the current economic climate and lower oil prices.

"Of course it is not only about Thursday's results. It is also about the foundations for future growth and 2008 was, in that respect, a year with real strategic momentum.

"With 13 new field discoveries -- the most significant of which are shown on this map -- exploration had one of its most successful years in the past decade. This included discoveries in the Gulf of Mexico, Angola, Algeria, Egypt and the North Sea -- we also completed the Libya deal -- which serves to highlight the strength and breadth of our exploration portfolio.

"We achieved significant new access -- to both undeveloped resources and new exploration acreage, particularly in North America.

"We were the successful bidder on three exploration licenses totaling 6,000 square kilometers in the arctic Canadian Offshore Continental Shelf. This is a particularly exciting prospect for the future, potentially containing some 20% of the world's yet to find hydrocarbons.

"In the middle of last year we extended our footprint in North America Gas through two deals with Chesapeake. Strategically, this gives us a material position in three top-tier shale basins and creates a balanced portfolio of conventional gas, tight gas, coalbed methane and now shale gas, in the world's biggest natural gas market.

Hayward said, "We have a world class resource base and our improving track record for executing projects gives us real confidence for the future. Last year we said we expected to grow production to 2012, and that we could maintain it out to 2020 from existing projects. The picture is quietly and steadily improving.

"We now expect to grow production between 1 and 2% out to 2013 based on existing projects and have the potential to continue the growth out to 2020.

"Linking now to our downstream business, we concluded the oil sands deal with Husky. A key aspect of the deal was to create an integrated position, with high-quality upstream resources linked to an upgraded U.S. refinery, allowing BP to capture the full value chain.

"We have just begun the upgrade of the Whiting refinery. Re-positioning Whiting towards heavy crude oil means it can take full advantage of Canadian differentials and the light-heavy spread - and will shift the yield of the refinery to higher value products.

"And finally, in Biofuels, we started production from our joint venture in Brazil. This is the largest single investment in Brazilian biofuels by an international oil company. Despite the economic downturn, we believe that a disciplined approach to Alternative Energy continues to offer good opportunities.

"So, not only have we closed our competitive performance gap, we are very well positioned for the future.

"Of course, we are facing the immediate challenge of the current economic climate and lower oil prices. In line with the increase in oil price -- illustrated by the green line on this chart - we have seen a steady increase in costs. Since 2004, when the oil price was at a comparable level to Thursday, our cost base has increased by about 50%.

"At BP, we started our drive to counter cost inflation some 18 months ago and managed to halt that inflationary trend in 2008 despite the continued rise in oil prices for most of the year."

The challenge for the industry now is to bring this cost base down -- and to do this fast, to align with the new market conditions.

The company has been working with its suppliers to improve efficiency by finding better ways to execute activity -- with one important caveat- safe and reliable operations come first whatever cost efficiency measures it undertakes.

And it continues to advance the safety and reliability of its operations through implementing its Operating Management System -- something that is fundamental to creating a culture of continuous improvement within BP.

The company aims in 2009 is to begin to roll back the inflationary trend by driving deflation into its business. Over the last few months, it has already seen sharp drops in the price of steel and petrochemicals. Its approach will be a proactive one. Based on the actions it took in 2008, and the deflation it can already see entering its supply chain, the company expects its costs to fall by around $2bn in 2009.

So, in this volatile environment, the company has kept a steady focus on what it said it would do.

He said, "Our goal is clear; to continue to invest for long term growth while retaining our focus on safe and reliable operations, paying the dividend and driving deflation into our cost base.

"At BP we have a mantra -- "every dollar counts, every seat counts" and we intend to follow it through. We have strong momentum on cost and operations - production is expected to continue to grow and refining availability is expected to be materially higher in 2009 than in 2008 - these underlying business improvements are expected to add to our cash flows in 2009.

"We have a strong balance sheet and based on our current plans, we expect cash inflows and outflows in 2009 to balance at an oil price of around $60 per barrel. That break-even point should continue to fall as we realize the benefits of our operational momentum and our action on costs.

Copyright (c) 2009 Dow Jones & Company, Inc.
Read more!

Ask me a question!

Looking for some answers to your problems? Want some advice with books and software? You have come to the right place. Ask any question related to petroleum engineering (geology, geophysics, reservoir, drilling and production) and i'll answer it for you via email or post the answer at Novel Inspiration. Use the link below to contact me with your queries. Start posting an just give me a week to reply!
Contact Me