- Crude oil
- Hydrocarbon exploration
- Natural gas
Saturday, September 5, 2009
Oil and gas
Oil and gas is a collective term that refers to liquid and gas hydrocarbons extracted from the subsurface. The term oil and gas may refer to:
Future of petroleum production
The future of petroleum as a fuel remains somewhat controversial. USA Today news reported in 2004 that there were 40 years of petroleum left in the ground. Some argue that because the total amount of petroleum is finite, the dire predictions of the 1970s have merely been postponed. Others claim that technology will continue to allow for the production of cheap hydrocarbons and that the earth has vast sources of unconventional petroleum reserves in the form of tar sands, bitumen fields and oil shale that will allow for petroleum use to continue in the future. They argue that both the Canadian tar sands and United States oil shale deposits represent potential reserves with just as much oil as current liquid petroleum deposits.
Price of petroleum
After the collapse of the OPEC-administered pricing system in 1985, and a short lived experiment with netback pricing, oil-exporting countries adopted a market-linked pricing mechanism.[25] First adopted by PEMEX in 1986, market-linked pricing received wide acceptance and by 1988 became and still is the main method for pricing crude oil in international trade.[25] The current reference, or pricing markers, are Brent, WTI .
Petroleum industry
The petroleum industry is involved in the global processes of exploration, extraction, refining, transporting (often with oil tankers and pipelines), and marketing petroleum products. The largest volume products of the industry are fuel oil and gasoline (petrol). Petroleum is also the raw material for many chemical products, including pharmaceuticals, solvents, fertilizers, pesticides, and plastics. The industry is usually divided into three major components: upstream, midstream and downstream. Midstream operations are usually included in the downstream category.
Petroleum is vital to many industries, and is of importance to the maintenance of industrialized civilization itself, and thus is critical concern to many nations. Oil accounts for a large percentage of the world’s energy consumption, ranging from a low of 32% for Europe and Asia, up to a high of 53% for the Middle East. Other geographic regions’ consumption patterns are as follows: South and Central America (44%), Africa (41%), and North America (40%). The world at large consumes 30 billion barrels (4.8 km³) of oil per year, and the top oil consumers largely consist of developed nations. In fact, 24% of the oil consumed in 2004 went to the United States alone [20], though by 2007 this had dropped to 21% of world oil consumed.
In the US, in the states of Arizona, California, Hawaii, Nevada, Oregon and Washington, the Western States Petroleum Association (WSPA) is responsible for producing, distributing, refining, transporting and marketing petroleum. This non-profit trade association was founded in 1907, and is the oldest petroleum trade association in the United States.
Petroleum is vital to many industries, and is of importance to the maintenance of industrialized civilization itself, and thus is critical concern to many nations. Oil accounts for a large percentage of the world’s energy consumption, ranging from a low of 32% for Europe and Asia, up to a high of 53% for the Middle East. Other geographic regions’ consumption patterns are as follows: South and Central America (44%), Africa (41%), and North America (40%). The world at large consumes 30 billion barrels (4.8 km³) of oil per year, and the top oil consumers largely consist of developed nations. In fact, 24% of the oil consumed in 2004 went to the United States alone [20], though by 2007 this had dropped to 21% of world oil consumed.
In the US, in the states of Arizona, California, Hawaii, Nevada, Oregon and Washington, the Western States Petroleum Association (WSPA) is responsible for producing, distributing, refining, transporting and marketing petroleum. This non-profit trade association was founded in 1907, and is the oldest petroleum trade association in the United States.
Sunday, August 30, 2009
Oil reserves
Oil reserves are the estimated quantities of crude oil that are claimed to be recoverable under existing economic and operating conditions.[1]
The total estimated amount of oil in an oil reservoir, including both producible and non-producible oil, is called oil in place. However, because of reservoir characteristics and limitations in petroleum extraction technologies, only a fraction of this oil can be brought to the surface, and it is only this producible fraction that is considered to be reserves. The ratio of producible oil reserves to total oil in place for a given field is often referred to as the recovery factor. Recovery factors vary greatly among oil fields. The recovery factor of any particular field may change over time based on operating history and in response to changes in technology and economics. The recovery factor may also rise over time if additional investment is made in enhanced oil recovery techniques such as gas injection, water-flooding[2], or microbial enhanced oil recovery.
Because the geology of the subsurface cannot be examined directly, indirect techniques must be used to estimate the size and recoverability of the resource. While new technologies have increased the accuracy of these techniques, significant uncertainties still remain. In general, most early estimates of the reserves of an oil field are conservative and tend to grow with time. This phenomenon is called reserves growth.[3]
Many oil producing nations do not reveal their reservoir engineering field data, and instead provide unaudited claims for their oil reserves. The numbers disclosed by some national governments are suspected of being manipulated for political reasons.
The total estimated amount of oil in an oil reservoir, including both producible and non-producible oil, is called oil in place. However, because of reservoir characteristics and limitations in petroleum extraction technologies, only a fraction of this oil can be brought to the surface, and it is only this producible fraction that is considered to be reserves. The ratio of producible oil reserves to total oil in place for a given field is often referred to as the recovery factor. Recovery factors vary greatly among oil fields. The recovery factor of any particular field may change over time based on operating history and in response to changes in technology and economics. The recovery factor may also rise over time if additional investment is made in enhanced oil recovery techniques such as gas injection, water-flooding[2], or microbial enhanced oil recovery.
Because the geology of the subsurface cannot be examined directly, indirect techniques must be used to estimate the size and recoverability of the resource. While new technologies have increased the accuracy of these techniques, significant uncertainties still remain. In general, most early estimates of the reserves of an oil field are conservative and tend to grow with time. This phenomenon is called reserves growth.[3]
Many oil producing nations do not reveal their reservoir engineering field data, and instead provide unaudited claims for their oil reserves. The numbers disclosed by some national governments are suspected of being manipulated for political reasons.
Classifications
Reserves are those quantities of petroleum claimed to be commercially recoverable by application of development projects to known accumulations under defined conditions.[6] Reserves must satisfy four criteria: They must be:
discovered through one or more exploratory wells[6]
recoverable using existing technology[6]
commercially viable[6]
remaining in the ground[6]
All reserve estimates involve uncertainty, depending on the amount of reliable geologic and engineering data available and the interpretation of those data. The relative degree of uncertainty can be expressed by dividing reserves into two principal classifications - proved and unproved.[6] Unproved reserves can further be divided into two subcategories - probable and possible to indicate the relative degree of uncertainty about their existence.[6] The most commonly accepted definitions of these are based on those approved by the Society of Petroleum Engineers (SPE) and the World Petroleum Council (WPC) in 1997
discovered through one or more exploratory wells[6]
recoverable using existing technology[6]
commercially viable[6]
remaining in the ground[6]
All reserve estimates involve uncertainty, depending on the amount of reliable geologic and engineering data available and the interpretation of those data. The relative degree of uncertainty can be expressed by dividing reserves into two principal classifications - proved and unproved.[6] Unproved reserves can further be divided into two subcategories - probable and possible to indicate the relative degree of uncertainty about their existence.[6] The most commonly accepted definitions of these are based on those approved by the Society of Petroleum Engineers (SPE) and the World Petroleum Council (WPC) in 1997
Proved reserves
Proved reserves are those reserves claimed to have a reasonable certainty (normally at least 90% confidence) of being recoverable under existing economic and political conditions, with existing technology. Industry specialists refer to this as P90 (i.e. having a 90% certainty of being produced). Proved reserves are also known in the industry as 1P.[8][9]
Proved reserves are further subdivided into Proved Developed (PD) and Proved Undeveloped (PUD).[9][10] PD reserves are reserves that can be produced with existing wells and perforations, or from additional reservoirs where minimal additional investment (operating expense) is required.[10] PUD reserves require additional capital investment (e.g. drilling new wells) to bring the oil to the surface.[8][10]
Proved reserves are the only type the U.S. Securities and Exchange Commission allows oil companies to report to investors. Companies listed on U.S. stock exchanges must substantiate their claims, but many governments and national oil companies do not disclose verifying data to support their claims.
Proved reserves are further subdivided into Proved Developed (PD) and Proved Undeveloped (PUD).[9][10] PD reserves are reserves that can be produced with existing wells and perforations, or from additional reservoirs where minimal additional investment (operating expense) is required.[10] PUD reserves require additional capital investment (e.g. drilling new wells) to bring the oil to the surface.[8][10]
Proved reserves are the only type the U.S. Securities and Exchange Commission allows oil companies to report to investors. Companies listed on U.S. stock exchanges must substantiate their claims, but many governments and national oil companies do not disclose verifying data to support their claims.
Unproved reserves
Unproved reserves are based on geological and/or engineering data similar to that used in estimates of proved reserves, but technical, contractual, or regulatory uncertainties preclude such reserves being classified as proved. [11] Unproved reserves may be used internally by oil companies and government agencies for future planning purposes, but are not routinely compiled. They are sub classified as probable and possible [11]
Probable reserves are are attributed to known accumulations, and claim a 50% confidence level of recovery. Industry specialists refer to this as P50 (i.e. having a 50% certainty of being produced). Referred to in the industry as 2P (proved plus probable).[8]
Possible reserves are attributed to known accumulations which have a less likely chance of being recovered than probable reserves. This term is often used for reserves which are claimed to have at least a 10% certainty of being produced (P10). Reasons for classifying reserves as possible include varying interpretations of geology, reserves not producible at commercial rates, uncertainty due to reserve infill (seepage from adjacent areas), projected reserves based on future recovery methods. Referred to in the industry as 3P (proved plus probable plus possible).
Probable reserves are are attributed to known accumulations, and claim a 50% confidence level of recovery. Industry specialists refer to this as P50 (i.e. having a 50% certainty of being produced). Referred to in the industry as 2P (proved plus probable).[8]
Possible reserves are attributed to known accumulations which have a less likely chance of being recovered than probable reserves. This term is often used for reserves which are claimed to have at least a 10% certainty of being produced (P10). Reasons for classifying reserves as possible include varying interpretations of geology, reserves not producible at commercial rates, uncertainty due to reserve infill (seepage from adjacent areas), projected reserves based on future recovery methods. Referred to in the industry as 3P (proved plus probable plus possible).
Oil, gas reserves discovered
ISLAMABAD (APP) - The Oil and Gas Development Company Limited (OGDCL) as operator along with its joint venture partners Government Holdings (Pvt) Limited (GHPL) and Orient Petroleum International Inc. (OPII) has discovered oil and gas reserves in Sanghar City, Sindh Province.OGDCL sources told APP that the Company as operator along with its joint venture partners has discovered oil and gas reserves from its exploratory Well Baloch #01, in Sinjhoro Exploration License which is located at a distance of 22.5 km North West of Sanghar City, Sindh Province.The structure of Baloch Well # 01 was delineated drilled and tested by OGDCL’s in house expertise.The well was drilled down to the depth of 3463 meters, targeting to test the potential of sand body (Massive Sands) of Lower Goru formation of Cretaceous age.The significant reserves of hydrocarbons have been found at Baloch Well#01. The hydrocarbon bearing Zone comprising of 32.5 meters has tested 780 BBL of oil per day and about 3.5 MMCFD of gas through 32/64" choke, at well head flowing pressure of 880 Psi.
Oil refinery
An oil refinery is an industrial process plant where crude oil is processed and refined into more useful petroleum products, such as gasoline, diesel fuel, asphalt base, heating oil, kerosene, and liquefied petroleum gas. Oil refineries are typically large sprawling industrial complexes with extensive piping running throughout, carrying streams of fluids between large chemical processing units.
Exploration methods of Oil
Visible surface features such as oil seeps, natural gas seeps, pockmarks (underwater craters caused by escaping gas) provide basic evidence of hydrocarbon generation (be it shallow or deep in the Earth). However, most exploration depends on highly sophisticated technology to detect and determine the extent of these deposits using exploration geophysics. Areas thought to contain hydrocarbons are initially subjected to a gravity survey, magneic survey, passi seismicor regional seismic reflection surveys to detect large scale features of the sub-surface geology. Features of interest (known as leads) are subjected to more detailed seismic surveys which work on the principle of the time it takes for reflected sound waves to travel through matter (rock) of varying densities and using the process of depth conversion to create a profile of the substructure. Finally, when a prospect has been identified and evaluated and passes the oil company's selection criteria, an exploration well is drilled in an attempt to conclusively determine the presence or absence of oil or gas.Oil exploration is an expensive, high-risk operation. Offshore and remote area exploration is generally only undertaken by very large corporations or national governments. Typical Shallow shelf oil wells (e.g. North sea) cost USD$10 - 30 Million, while deep water wells can cost up to USD$100 million plus. Hundreds of smaller companies search for onshore hydrocarbon deposits worldwide, with some wells costing as little as USD$100,000.
Oil and Gas Companies All Over The World
Abu Dhabi National Oil Company (ADNOC).
AGIP (Azienda Generale Italiana Petroli) since 1998 ENI-Agip Exploration and Production.
Anglo Siberian Oil Company plc.
Anonima Petroli Italiana (API)
AnzoilARCO (Atlantic Richfield Company) = BP-Amoco.
Australian Oil & Gas Corporation Ltd.
Australian Worldwide Exploration LimitedBay State Gas.
Bentec Drilling (Preussag DE).Benton Oil & Gas Company.
BHP Billiton.BJ Services Company.
Black Hills Exploration and Production.
(US).BP Amoco ARCO.
Chieftain International (now: Huntoil).
Chinese Petroleum Corporation (Taiwan TW).
Compagnie Générale de Géophysique (CGG).CONOCO (US) (incl. Gulf Canada).
ConocoPhillips.CSIRO Exploration and Mining.
Dana Petroleum plc.Deutag Drilling (Preussag DE) (now: KCA DEUTAG Drilling Limited)Devon Energy Corporation (US) (incl. Santa Fe Snyder Corporation, PennzEnergy).
Dominion Exploration & Production.Elf Aquitaine (TOTAL FINA ELF).
Empresa Colombiana de Petróleos (ECOPETROL).
Empresa Nacional del Petróleo - Chile (ENAP).
Encana.Energy Africa EA.Eni.Enterprise Oil plc. (UK).
Equity Oil Company.ESSO DeutschlandEvergreen Resources (US)ExxonMobilFINA (now:
Oil well
An oil well is a general term for any boring through the Earth's surface designed to find and produce petroleum oil hydrocarbons. Usually some natural gas is produced along with the oil, and a well designed to produce mainly or only gas may be termed a gas well.
Life of a well
The creation and life of a well can be divided up into five segments:
- Planning
- Drilling
- Completion
- Production
- Abandonment
Drilling
The well is created by drilling a hole 5 to 36 inches (127.0 mm to 914.4 mm) diameter into the earth with a drilling rig which rotates a drill string with a bit attached. After the hole is drilled, sections of steel tubing (casing), slightly smaller in diameter than the borehole, are placed in the hole. Cement may be placed between the outside of the casing and the borehole. The casing provides structural integrity to the newly drilled wellbore in addition to isolating potentially dangerous high pressure zones from each other and from the surface.With these zones safely isolated and the formation protected by the casing, the well can be drilled deeper (into potentially more-unstable and violent formations) with a smaller bit, and also cased with a smaller size casing. Modern wells often have 2-5 sets of subsequently smaller hole sizes drilled inside one another, each cemented with casing.To drill the well
The drill bit, aided by the weight of thick walled pipes called "drill collars" above it, cuts into the rock. There are different types of drillbit, some cause the rock to fail by compressive failure. Others shear slices off the rock as the bit turns.
Drilling fluid (aka "mud") is pumped down the inside of the drill pipe and exits at the drill bit. Drilling mud is a complex mixture of fluids, solids and chemicals which must be carefully tailored to provide the correct physical and chemical characteristics required to safely drill the well., Particular functions of the drilling mud include cooling the bit, lifting rock cuttings to the surface, preventing destabilisation of the rock in the wellbore walls and overcoming the pressure of fluids inside the rock so that these fluids don't enter the wellbore.
The generated rock "cuttings" are swept up by the drilling fluid as it circulates back to surface outside the drill pipe. The fluid then goes through "shakers" which strain the cuttings from the good fluid which is returned to the pit. Watching for abnormalities in the returning cuttings and monitoring pit volume or rate of returning fluid are imperative to catch "kicks" (when the formation pressure at the depth of the bit is more than the hydrostatic head of the mud above, which if not controlled temporarily by closing the blowout preventers and ultimately by increasing the density of the drilling fluid would allow formation fluids and mud to come up uncontrollably) early.
The pipe or drill string to which the bit is attached is gradually lengthened as the well gets deeper by screwing in additional 30-foot (10 m) joints (i.e., sections) of pipe under the kelly or topdrive at the surface. This process is called making a connection. Usually joints are combined into 3 joints equaling 1 stand. Some smaller rigs only use 2 joints and some rigs can handle stands of 4 joints.This process is all facilitated by a drilling rig which contains all necessary equipment to circulate the drilling fluid, hoist and turn the pipe, control downhole pressures, remove cuttings from the drilling fluid, and generate onsite power for these operations.
The drill bit, aided by the weight of thick walled pipes called "drill collars" above it, cuts into the rock. There are different types of drillbit, some cause the rock to fail by compressive failure. Others shear slices off the rock as the bit turns.
Drilling fluid (aka "mud") is pumped down the inside of the drill pipe and exits at the drill bit. Drilling mud is a complex mixture of fluids, solids and chemicals which must be carefully tailored to provide the correct physical and chemical characteristics required to safely drill the well., Particular functions of the drilling mud include cooling the bit, lifting rock cuttings to the surface, preventing destabilisation of the rock in the wellbore walls and overcoming the pressure of fluids inside the rock so that these fluids don't enter the wellbore.
The generated rock "cuttings" are swept up by the drilling fluid as it circulates back to surface outside the drill pipe. The fluid then goes through "shakers" which strain the cuttings from the good fluid which is returned to the pit. Watching for abnormalities in the returning cuttings and monitoring pit volume or rate of returning fluid are imperative to catch "kicks" (when the formation pressure at the depth of the bit is more than the hydrostatic head of the mud above, which if not controlled temporarily by closing the blowout preventers and ultimately by increasing the density of the drilling fluid would allow formation fluids and mud to come up uncontrollably) early.
The pipe or drill string to which the bit is attached is gradually lengthened as the well gets deeper by screwing in additional 30-foot (10 m) joints (i.e., sections) of pipe under the kelly or topdrive at the surface. This process is called making a connection. Usually joints are combined into 3 joints equaling 1 stand. Some smaller rigs only use 2 joints and some rigs can handle stands of 4 joints.This process is all facilitated by a drilling rig which contains all necessary equipment to circulate the drilling fluid, hoist and turn the pipe, control downhole pressures, remove cuttings from the drilling fluid, and generate onsite power for these operations.
Completion
After drilling and casing the well, it must be 'completed'. Completion is the process in which the well is enabled to produce oil or gas.In a cased-hole completion, small holes called perforations are made in the portion of the casing which passed through the production zone, to provide a path for the oil to flow from the surrounding rock into the production tubing. In open hole completion, often 'sand screens' or a 'gravel pack' is installed in the last drilled, uncased reservoir section. These maintain structural integrity of the wellbore in the absence of casing, while still allowing flow from the reservoir into the wellbore. Screens also control the migration of formation sands into production tubulars and surface equipment, which can cause washouts and other problems, particularly from unconsolidated sand formations in offshore fields.After a flow path is made, acids and fracturing fluids are pumped into the well to fracture, clean, or otherwise prepare and stimulate the reservoir rock to optimally produce hydrocarbons into the wellbore. Finally, the area above the reservoir section of the well is packed off inside the casing, and connected to the surface via a smaller diameter pipe called tubing. This arrangement provides a redundant barrier to leaks of hydrocarbons as well as allowing damaged sections to be replaced. Also, the smaller diameter of the tubing produces hydrocarbons at an increased velocity in order to overcome the hydrostatic effects of heavy fluids such as water.In many wells, the natural pressure of the subsurface reservoir is high enough for the oil or gas to flow to the surface. However, this is not always the case, especially in depleted fields where the pressures have been lowered by other producing wells, or in low permeability oil reservoirs. Installing a smaller diameter tubing may be enough to help the production, but artificial lift methods may also be needed. Common solutions include downhole pumps, gas lift, or surface pump jacks. Many new systems in the last ten years have been introduced for well completion. Multiple packer systems with frac ports or port collars in an all in one system have cut completion costs and improved production, especially in the case of horizontal wells. These new systems allow casings to run into the lateral zone with proper packer/frac port placement for optimal hydrocarbon recovery.Production
The production stage is the most important stage of a well's life, when the oil and gas are produced. By this time, the oil rigs and workover rigs used to drill and complete the well have moved off the wellbore, and the top is usually outfitted with a collection of valves called a production tree. These valves regulate pressures, control flows, and allow access to the wellbore in case further completion work is needed. From the outlet valve of the production tree, the flow can be connected to a distribution network of pipelines and tanks to supply the product to refineries, natural gas compressor stations, or oil export terminals.As long as the pressure in the reservoir remains high enough, the production tree is all that is required to produce the well. If the pressure depletes and it is considered economically viable, an artificial lift method mentioned in the completions section can be employed.Workovers are often necessary in older wells, which may need smaller diameter tubing, scale or paraffin removal, acid matrix jobs, or completing new zones of interest in a shallower reservoir. Such remedial work can be performed using workover rigs – also known as pulling units or completion rigs – to pull and replace tubing, or by the use of well intervention techniques utilizing coiled tubing. Depending on the type of lift system and wellhead a rod rig or flushby can be used to change a pump without pulling the tubing.Enhanced recovery methods such as water flooding, steam flooding, or CO2 flooding may be used to increase reservoir pressure and provide a "sweep" effect to push hydrocarbons out of the reservoir. Such methods require the use of injection wells (often chosen from old production wells in a carefully determined pattern), and are used when facing problems with reservoir pressure depletion, high oil viscosity, or can even be employed early in a field's life. In certain cases – depending on the reservoir's geomechanics – reservoir engineers may determine that ultimate recoverable oil may be increased by applying a waterflooding strategy early in the field's development rather than later. Such enhanced recovery techniques are often called "tertiary recovery".
Abandonment
When the well no longer produces or produces so poorly that it is a liability, it is abandoned. In this process, tubing is removed from the well and sections of well bore are filled with cement to isolate the flow path between gas and water zones from each other, as well as the surface. Completely filling the well bore with cement is costly and unnecessary. The surface around the wellhead is then excavated, and the wellhead and casing are cut off, a cap is welded in place and then buried.The point at which the well no longer makes a profit and is plugged and abandoned is called the “economic limit.” The equation to determine the economic limit contains four factors, namely: (1) taxes, (2) operating cost, (3) oil price, and (4) royalty. When oil taxes are raised, the economic limit is raised. When oil price is increased, the economic limit is lowered.When the economic limit is raised, the life of the well is decreased. Proven oil reserves are lost when the life of an oil well is decreased. Inversely, when the economic limit is lowered, the life of the well is increased. Proven oil reserves are increased when the life of the well is increased.At the economic limit there often is still a significant amount of unrecoverable oil left in the reservoir. It might be tempting to defer physical abandonment for an extended period of time, hoping that the oil price will go up or that new supplemental recovery techniques will be perfected. However, lease provisions and governmental regulations usually require quick abandonment; liability and tax concerns also may favor abandonment.In theory an abandoned well can be reentered and restored to production (or converted to injection service for supplemental recovery or for downhole hydrocarbons storage), but reentry often proves to be difficult mechanically and not cost effective.
Types of wells
Oil wells come in many varieties. By produced fluid, there can be wells that produce oil, wells that produce oil and natural gas, or wells that only produce natural gas. Natural gas is almost always a byproduct of producing oil, since the small, light gas carbon chains come out of solution as it undergoes pressure reduction from the reservoir to the surface, similar to uncapping a bottle of soda pop where the carbon dioxide effervesces. Unwanted natural gas can be a disposal problem at the well site. If there is not a market for natural gas near the wellhead it is virtually valueless since it must be piped to the end user. Until recently, such unwanted gas was burned off at the wellsite, but due to environmental concerns this practice is becoming less common. Often, unwanted (or 'stranded' gas without a market) gas is pumped back into the reservoir with an 'injection' well for disposal or repressurizing the producing formation. Another solution is to export the natural gas as a liquid.Gas-to-liquid, (GTL) is a developing technology that converts stranded natural gas into synthetic gasoline, diesel or jet fuel through the Fischer-Tropsch process developed in World War II Germany. Such fuels can be transported through conventional pipelines and tankers to users. Proponents claim GTL fuels burn cleaner than comparable petroleum fuels. Most major international oil companies are in advanced development stages of GTL production, with a world-scale (140,000 bbl/day) GTL plant in Qatar scheduled to come online before 2010. In locations such as the United States with a high natural gas demand, pipelines are constructed to take the gas from the wellsite to the end consumer.Another obvious way to classify oil wells is by land or offshore wells. There is very little difference in the well itself. An offshore well targets a reservoir that happens to be underneath an ocean. Due to logistics, drilling an offshore well is far more costly than an onshore well. By far the most common type is the onshore well. These wells dot the Southern and Central Great Plains, Southwestern United States, and are the most common wells in the Middle East.Another way to classify oil wells is by their purpose in contributing to the development of a resource. They can be characterized as:
- production wells are drilled primarily for producing oil or gas, once the producing structure and characteristics are determined
- appraisal wells are used to assess characteristics (such as flow rate) of a proven hydrocarbon accumulation
- exploration wells are drilled purely for exploratory (information gathering) purposes in a new area
- wildcat wells are those drilled outside of and not in the vicinity of known oil or gas fields.
Financial Times and Business Week recognises MBA Oil and Gas Management in 2009 distance learning rankings
The energy sector is facing some of its most profound changes. Global competition is forcing all organisations to concentrate on developing strong management competencies.
Studying the MBA Oil and Gas Management degree will enable you to develop not only advanced skills in strategy and management, but also a sound knowledge of energy management and an understanding of its importance in social, political, economic, cultural and technological respects to national and international strategy and the ability to apply this knowledge to inform decision-making.
The MBA Oil and Gas Management degree is designed to provide experienced practitioners in the oil and gas sector with the advanced business, management and leadership skills needed to function at a strategic level as a contemporary energy manager.
The course is aimed at middle to senior managers or those aspiring to these positions within the Oil and Gas industry.
This master of business administration degree offers significant choice to you in terms of oil and gas subject breadth, study mode and career path. The choice of energy industry focused modules caters for the full spectrum of oil and gas strategic management activities.
Studying the MBA Oil and Gas Management degree will enable you to develop not only advanced skills in strategy and management, but also a sound knowledge of energy management and an understanding of its importance in social, political, economic, cultural and technological respects to national and international strategy and the ability to apply this knowledge to inform decision-making.
The MBA Oil and Gas Management degree is designed to provide experienced practitioners in the oil and gas sector with the advanced business, management and leadership skills needed to function at a strategic level as a contemporary energy manager.
The course is aimed at middle to senior managers or those aspiring to these positions within the Oil and Gas industry.
This master of business administration degree offers significant choice to you in terms of oil and gas subject breadth, study mode and career path. The choice of energy industry focused modules caters for the full spectrum of oil and gas strategic management activities.
The MBA Oil and Gas Management degree is available full-time, part-time executive with online support or in an online study mode
The online MBA course has been listed in The Financial Times and Business Week as one of the Top Distance Learning MBAs available globally.
The MBA Oil and Gas Management curriculum is structured so that you will initially gain experience of all kinds of key decision-making in a range of business functions. This fundamental knowledge will then be applied at a strategic level in the strategic management module.
Within the specialist energy management modules you will gain a comprehensive knowledge of the theory, practice and execution of business decisions in the energy industry.
The project module will have an energy management focus and will give the you an opportunity to further synthesise and apply specialist knowledge to professional practice.
The choice of specialist modules are as follows:
- Energy Policy and the Environment
- Health, Safety and Risk in an Organisational Context
- Leadership, Communication and Change
- Change Management
- Oil and Gas Contract Law
- Oil and Gas Management
- Operations Management: Oil and Gas
- Petroleum Economics and Asset Management
- Project Fundamentals
You will be required to attend a Leadership Week and you will have the option of participating in a study tour to IAE Aix en Provence Université in the South of France.
Benefits and Aims of the MBA Oil and Gas Management Course
Our philosophy to the MBA Oil and Gas Management is that it should provide you with a toolbox of skills combined with a higher level of critical thinking that will stay with you for the rest of your life.
You will certainly develop better subject knowledge and how to apply strategic principles within the Oil and Gas industry. You will acquire improved communication skills, writing skills and leadership skills through the MBA experience. At a personal level you should gain higher levels of self-confidence, self esteem and improved individual strengths and abilities. Ultimately this will lead to more business experience which in turn will result in a better chance of a more responsible job, higher satisfaction with your current job or the opportunity to change or focus your career.
You will certainly develop better subject knowledge and how to apply strategic principles within the Oil and Gas industry. You will acquire improved communication skills, writing skills and leadership skills through the MBA experience. At a personal level you should gain higher levels of self-confidence, self esteem and improved individual strengths and abilities. Ultimately this will lead to more business experience which in turn will result in a better chance of a more responsible job, higher satisfaction with your current job or the opportunity to change or focus your career.
Leadership Workshop
In late May each year the school hosts an MBA leadership workshop. This is an intensive 6 day event with guest speakers from academia and industry. You will experience an outdoor leadership development day and a career leadership event. The attendees also include executives from local businesses.
Study Tour - IAE Aix-en-Provence: Graduate School of Management
The MBA class participates in the study tour to the South of France in June each year. Outline curriculum for study tour:
Day 1: Intercultural Communication Process and Styles Flash Session Day 2 - 5: Business at the Intersection: An interdisciplinary way to look at business
This study tour is delivered by speakers from IAE Aix-en-Provence Graduate Management School, Washington University’s John M. Olin School of Business and the Allen Center for Executive Education at Northwestern University.
Day 1: Intercultural Communication Process and Styles Flash Session Day 2 - 5: Business at the Intersection: An interdisciplinary way to look at business
This study tour is delivered by speakers from IAE Aix-en-Provence Graduate Management School, Washington University’s John M. Olin School of Business and the Allen Center for Executive Education at Northwestern University.
MBA Tutoring and Professional Development
During the MBA Oil and Gas Management course, full-time students will be paired with an academic tutor. Your MBA tutor will offer help in areas such as advice on careers, managing work-life, networking and so on. Students will participate in a number of professional development exercises aimed at helping you understand where your career is going, appreciating your personal strengths and weaknesses, and developing and reinforcing core competencies and skills.
Career Counselling
All students have access to one-to-one career counselling through our careers office. The MBA team work hard with the careers office to develop dedicated resources and seminars for MBA students.
MBA Alumni Association
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Petroleum geology
Petroleum geology refers to the specific set of geological disciplines that are applied to the search for hydrocarbons (oil exploration).
Sedimentary basin analysis
Petroleum geology is principally concerned with the evaluation of seven key elements in sedimentary basins:
- Source
- Reservoir
Seal - Trap
- Timing
- Maturation
- Migration
In general, all these elements must be assessed via a limited 'window' into the subsurface world, provided by one (or possibly more) exploration wells. These wells present only a 1-dimensional segment through the Earth and the skill of inferring 3-dimensional characteristics from them is one of the most fundamental in petroleum geology. Recently, the availability of cheap and high quality 3D seismic data (from reflection seismology) has greatly aided the accuracy of such interpretation. The following section discusses these elements in brief. For a more in-depth treatise, see the second half of this article below.
Evaluation of the source uses the methods of geochemistry to quantify the nature of organic-rich rocks which contain the precursors to hydrocarbons, such that the type and quality of expelled hydrocarbon can be assessed.
Major subdisciplines in petroleum geology
Several major subdisciplines exist in petroleum geology specifically to study the seven key elements discussed above.
Analysis of source rocks
In terms of source rock analysis, several facts need to be established. Firstly, the question of whether there actually is any source rock in the area must be answered. Delineation and identification of potential source rocks depends on studies of the local stratigraphy, palaeogeography and sedimentology to determine the likelihood of organic-rich sediments having been deposited in the past.
If the likelihood of there being a source rock is thought to be high, the next matter to address is the state of thermal maturity of the source, and the timing of maturation. Maturation of source rocks (see diagenesis and fossil fuels) depends strongly on temperature, such that the majority of oil generation occurs in the 60° to 120°C range. Gas generation starts at similar temperatures, but may continue up beyond this range, perhaps as high as 200°C. In order to determine the likelihood of oil/gas generation, therefore, the thermal history of the source rock must be calculated. This is performed with a combination of geochemical analysis of the source rock (to determine the type of kerogens present and their maturation characteristics) and basin modelling methods, such as back-stripping, to model the thermal gradient in the sedimentary column.
If the likelihood of there being a source rock is thought to be high, the next matter to address is the state of thermal maturity of the source, and the timing of maturation. Maturation of source rocks (see diagenesis and fossil fuels) depends strongly on temperature, such that the majority of oil generation occurs in the 60° to 120°C range. Gas generation starts at similar temperatures, but may continue up beyond this range, perhaps as high as 200°C. In order to determine the likelihood of oil/gas generation, therefore, the thermal history of the source rock must be calculated. This is performed with a combination of geochemical analysis of the source rock (to determine the type of kerogens present and their maturation characteristics) and basin modelling methods, such as back-stripping, to model the thermal gradient in the sedimentary column.
Analysis of reservoir
The existence of a reservoir rock (typically, sandstones and fractured limestones) is determined through a combination of regional studies (i.e. analysis of other wells in the area), stratigraphy and sedimentology (to quantify the pattern and extent of sedimentation) and seismic interpretation. Once a possible hydrocarbon reservoir is identified, the key physical characteristics of a reservoir that are of interest to a hydrocarbon explorationist are its porosity and permeability. Traditionally, these were determined through the study of hand specimens, contiguous parts of the reservoir that outcrop at the surface and by the technique of formation evaluation using wireline tools passed down the well itself. Modern advances in seismic data acquisition and processing have meant that seismic attributes of subsurface rocks are readily available and can be used to infer physical/sedimentary properties of the rocks themselves.
Exploration geophysics
Exploration geophysics is the applied branch of geophysics which uses surface methods to measure the physical properties of the subsurface Earth, in order to detect or infer the presence and position of concentrations of ore minerals and hydrocarbons.
Exploration geophysics is the practical application of physical methods (such as seismic, gravitational, magnetic, electrical and electromagnetic) to measure the physical properties of rocks, and in particular, to detect the measurable physical differences between rocks that contain ore deposits or hydrocarbons and those without.
Exploration geophysics can be used to directly detect the target style of mineralisation, via measuring its physical properties directly. For example one may measure the density contrasts between iron ore and silicate wall rocks, or may measure the conductivity contrast between conductive sulfide minerals and barren silicate minerals.
Exploration geophysics is the practical application of physical methods (such as seismic, gravitational, magnetic, electrical and electromagnetic) to measure the physical properties of rocks, and in particular, to detect the measurable physical differences between rocks that contain ore deposits or hydrocarbons and those without.
Exploration geophysics can be used to directly detect the target style of mineralisation, via measuring its physical properties directly. For example one may measure the density contrasts between iron ore and silicate wall rocks, or may measure the conductivity contrast between conductive sulfide minerals and barren silicate minerals.
Geophysical Methods
The following techniques are used:
- Seismic methods, such as reflection seismology, seismic refraction, refraction microtremor
- (ReMi) and seismic tomography.
- Magnetotellurics
- Scientific drilling
- Transient electromagnetic (EM) (see, e.g. Geonics instruments)
- Radio frequency electromagnetic propagation (e.g., ground penetrating radar)
- Electrical techniques, including Electrical resistivity tomography and induced polarization
- Magnetic techniques, including aeromagnetic surveys and magnetometers.
- Gravity and Gravity Gradiometry
- Geodesy
- Remote sensing
- Seismoelectrical Method
Uses
Exploration geophysics is also used to map the subsurface structure of a region, to elucidate the underlying structures, spatial distribution of rock units, and to detect structures such as faults, folds and intrusive rocks. This is an indirect method for assessing the likelihood of ore deposits or hydrocarbon accumulations.
Methods devised for finding mineral or hydrocarbon deposits can also be used in other areas such as monitoring environmental impact, imaging subsurface archaeological sites, ground water investigations, subsurface salinity mapping, civil engineering site investigations and interplanetary imaging.
Methods devised for finding mineral or hydrocarbon deposits can also be used in other areas such as monitoring environmental impact, imaging subsurface archaeological sites, ground water investigations, subsurface salinity mapping, civil engineering site investigations and interplanetary imaging.
Mineral exploration
Magnetometric surveys can be useful in defining magnetic anomalies which represent ore (direct detection), or in some cases gangue minerals associated with ore deposits (indirect or inferential detection).
The most direct method of detection of ore via magnetism involves detecting iron ore mineralisation via mapping magnetic anomalies associated with banded iron formations which usually contain magnetite in some proportion. Skarn mineralisation, which often contains magnetite, can also be detected though the ore minerals themselves would be non-magnetic. Similarly, magnetite, hematite and often pyrrhotite are common minerals associated with hydrothermal alteration, and this alteration can be detected to provide an inference that some mineralising hydrothermal event has affected the rocks.
Gravity surveying can be used to detect dense bodies of rocks within host formations of less dense wall rocks. This can be used to directly detect Mississippi Valley Type ore deposits, IOCG ore deposits, iron ore deposits, skarn deposits and salt diapirs which can form oil and gas traps.
Electro-magnetic (EM) surveys can be used to detect a wide variety of base metal sulphide deposits via detection of conductivity anomalies which can be generated around sulphide bodies in the subsurface. EM surveys can also be used to detect palaeochannel-hosted uranium deposits which are associated with shallow aquifers, which often respond to EM surveys in conductive overburden. This is an indirect inferrential method of detecting mineralisation.
Regional EM surveys are conducted via airborne methods, utilising either fixed-wing aircraft or helicopter-borne EM rigs. Surface EM methods are based mostly on Transient EM methods utilising surface loops with a surface receiver, or a downhole tool lowered into a borehole which transects a body of mineralisation. These methods can map out sulphide bodies within the earth in 3 dimensions, and provide information to geologists to direct further exploratory drilling on known mineralisation. Surface loop surveys are rarely used for regional exploration, however in some cases such surveys can be used with success (eg; SQUID surveys for nickel orebodies).
Electric-resistance methods such as induced polarisation methods can be useful for directly detecting sulphide bodies, coal and resistive rocks such as salt and carbonates.
The most direct method of detection of ore via magnetism involves detecting iron ore mineralisation via mapping magnetic anomalies associated with banded iron formations which usually contain magnetite in some proportion. Skarn mineralisation, which often contains magnetite, can also be detected though the ore minerals themselves would be non-magnetic. Similarly, magnetite, hematite and often pyrrhotite are common minerals associated with hydrothermal alteration, and this alteration can be detected to provide an inference that some mineralising hydrothermal event has affected the rocks.
Gravity surveying can be used to detect dense bodies of rocks within host formations of less dense wall rocks. This can be used to directly detect Mississippi Valley Type ore deposits, IOCG ore deposits, iron ore deposits, skarn deposits and salt diapirs which can form oil and gas traps.
Electro-magnetic (EM) surveys can be used to detect a wide variety of base metal sulphide deposits via detection of conductivity anomalies which can be generated around sulphide bodies in the subsurface. EM surveys can also be used to detect palaeochannel-hosted uranium deposits which are associated with shallow aquifers, which often respond to EM surveys in conductive overburden. This is an indirect inferrential method of detecting mineralisation.
Regional EM surveys are conducted via airborne methods, utilising either fixed-wing aircraft or helicopter-borne EM rigs. Surface EM methods are based mostly on Transient EM methods utilising surface loops with a surface receiver, or a downhole tool lowered into a borehole which transects a body of mineralisation. These methods can map out sulphide bodies within the earth in 3 dimensions, and provide information to geologists to direct further exploratory drilling on known mineralisation. Surface loop surveys are rarely used for regional exploration, however in some cases such surveys can be used with success (eg; SQUID surveys for nickel orebodies).
Electric-resistance methods such as induced polarisation methods can be useful for directly detecting sulphide bodies, coal and resistive rocks such as salt and carbonates.
Oil and gas
Seismic tomography, seismic reflection and 3D seismic surveying is the geophysical exploration technique most commonly used in the onshore and offshore petrochemical exploration industries. Seismic reflection techniques are used to map the subsurface distribution of stratigraphy and its structure, which can be used to map out hydrocarbon plays; seismic refraction parameters are used to calculate the density of the subsurface layers to determine such parameters as density, porosity and rock type.
Downhole geophysics tools are used within oil and gas exploration for several purposes;
Downhole geophysics tools are used within oil and gas exploration for several purposes;
- density tools measure rock density and porosity
- caliper tools measure hole diameter
- gamma-logging tools measure the radioactivity of the wall rocks in the bore hole
- EM tools measure wall-rock conductivity - to inform on porosity, sulphide content, lithology, etc.
Civil engineering
Ground penetrating radar is utilised within civil construction and engineering for a variety of uses, including detection of utilities (buried water, gas, sewerage, electrical and telecommunication cables), mapping of soft soils and overburden for geotechnical characterisation, and other similar uses.
Civil engineering can also utilise remote sensing information for topographical mapping, planning and environmental impact assessment. Airborne electromagnetic surveys are also used to characterise soft sediments in planning and engineering roads, dams and other structures.
Civil engineering can also utilise remote sensing information for topographical mapping, planning and environmental impact assessment. Airborne electromagnetic surveys are also used to characterise soft sediments in planning and engineering roads, dams and other structures.
Archaeology
Ground penetrating radar can be used to map buried artefacts, such as graves, mortuaries, wreck sites, and other shallowly buried archaological sites.
Ground magnetometric surveys can be used for detecting buried ferrous metals, useful in surveying shipwrecks, modern battlefields strewn with metal debris, and even subtle disturbances such as large-scale ancient ruins.
Sonar systems can be used to detect shipwrecks.
Ground magnetometric surveys can be used for detecting buried ferrous metals, useful in surveying shipwrecks, modern battlefields strewn with metal debris, and even subtle disturbances such as large-scale ancient ruins.
Sonar systems can be used to detect shipwrecks.
Exploration geophysics in society
In addition to universities and technical institutes such as the Colorado School of Mines, University of British Columbia, Curtin University, professional societies such as the Society of Exploration Geophysicists (SEG) (seg.org) and the CSEG and ASEG have the most recent updates of the sciences and technologies of exploration geophysics.
Exploration Geophysics careers are in such widely varying industries as oil & gas exploration, mining, environmental studies, planetary physics and even archaeology.
Exploration Geophysics careers are in such widely varying industries as oil & gas exploration, mining, environmental studies, planetary physics and even archaeology.
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