Survey for Searching Oil and Gas

Sesmic Survey

The search for oil and gas requires a knowledge of geography, geology and geophysics. Crude oil is usually found in certain types of geological structures, such as anticlines, fault traps and salt domes, which lie under various terrains and in a wide range of climates. After selecting an area of interest, many different types of geophysical surveys are conducted and measurements performed in order to obtain a precise evaluation of the subsurface formations, including:

• Magnetometric surveys. Magnetometers hung from airplanes measure variations in the earth’s magnetic field in order to locate sedimentary rock formations which generally have low magnetic properties when compared to other rocks.

• Aerial photogrammetric surveys. Photographs taken with special cameras in airplanes, provide three-dimensional views of the earth which are used to determine land formations with potential oil and gas deposits.

• Gravimetric surveys. Because large masses of dense rock increase the pull of gravity, gravimeters are used to provide information regarding underlying formations by measuring minute differences in gravity.

• Seismic surveys. Seismic studies provide information on the general characteristics of the subsurface structure. Measurements are obtained from shock waves generated by setting off explosive charges in small-diameter holes, from the use of vibrating or percussion devices on both land and in water, and from underwater blasts of compressed air. The elapsed time between the beginning of the shock wave and the return of the echo is used to determine the depth of the reflecting substrata. The recent use of super-computers to generate three-dimensional images greatly improves evaluation of seismic test results.
• Radiographic surveys. Radiography is the use of radio waves to provide information similar to that obtained from seismic surveys.

• Stratigraphic surveys. Stratigraphic sampling is the analysis of cores of subsurface rock strata for traces of gas and oil. A cylindrical length of rock, called a core, is cut by a hollow bit and pushed up into a tube (core barrel) attached to the bit. The core barrel is brought to the surface and the core is removed for analysis.

When the surveys and measurements indicate the presence of formations or strata which may contain petroleum, exploratory wells are drilled to determine whether or not oil or gas is actually present and, if so, whether it is available and obtainable in commercially viable quantities.

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Well’s Production prediction with Microseismic Technology

With efficiency being crucial when every dollar counts, operators in unconventional plays could add microseismic technology to fracture modeling methods to gain insight into permeability advances and better forecast production.

That’s according to Sudhendu Kashikar, vice president of completions evaluation for MicroSeismic Inc.

Understanding drainage volume and improved permeability of stimulated rock are essential to forecasting production, he said. Typically, several models are used to accomplish this, but the approach has its drawbacks.

A single frack model per stage ignores geological variations along the wellbore. Plus, a discrete fracture network (DFN) model is needed to determine how fracturing actually improves the permeability of stimulated rock, Kashikar said.

Microseismic techniques can simplify the workflow and help with production forecasting, Kashikar said during a webcast June 16.

“Technology and procedures were developed to discriminate the microseismic events and fractures described by these events, capturing propped versus unpropped fractures,” Kashikar said while describing Productive-stimulated rock volume (Productive-SRV) technology. “A rock volume capturing the proppant-filled refractures showed much better correlation to the cumulative production than the total stimulated rock volume.”

Productive-SRV technology estimates how much stimulated fracture remains open through proppant placement by using estimated target zone productivity, a DFN, propped fracture estimate and the Fat Fracture drainage estimate, according to MicroSeismic’s website.

Focus is usually on the location of the proppant, but focus should also be on the amount of improved permeability achieved within the SRV or the Productive-SRV, he said.

Understanding and measuring such improvements will lead to the next step in reservoir stimulation and production forecasting, he said.

Using microseismic data has proven beneficial in establishing a deterministic DFN, which shows fractures detected through seismic.

“For every microseismic event we describe a fracture plane. The size is guided by the magnitude, and the orientation comes from the focal mechanism,” he said. “This is much easier to do with surface microseismic.”

The model is calibrated to actual fluid volumes pumped for a well. A mass balance approach is used to fill the fractures with proppant starting from the wellbore moving outward until the proppant is consumed for that stage, Kashikar explained. Once the fracture network and the propped network have been established, a geocellular grid can be superimposed to obtain the SRV and productive SRV to capture the proppant-filled rock volume, he said.

“One advantage of this workflow is the ability to capture fracture intensity—the number of fractures, the orientation of these fractures—to quantify the permeability enhancement achieved,” Kashikar added.

Key steps for the production forecasting workflow are describing three reservoir volumes—the productive SRV (the propped fractures), total SRV (includes propped and unpropped fractures) and the permeability scalar for individual cells within each region to determine how permeability improved for neighboring cells.

This workflow, he said, captures not only the size and shape of the drainage volume but also permeability within the drainage volume.

The process is a big step forward, he said, in understanding and determining the effectiveness of hydraulic fracturing.

“Rather than relying on a single representative fracture model, we can fully and accurately capture the variable fracture geometry and fracture intensity for the entire length of the wellbore, providing a much better production forecast,” Kashikar said. “We can now use the productive stimulated rock volume and the stimulated rock volume with permeability scalars to directly and explicitly describe the reservoir volume in the reservoir simulator.”

Source: www.epmag.com

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Oil Exploration With Gravity And Magnetic Geophysical Methods

Gravity and magnetic methods are an essential part of oil exploration. They do not replace seismic. Rather, they add to it. Despite being comparatively low-resolution, they have some very big advantages.

These geophysical methods passively measure natural variations in the earth’s gravity and magnetic fields over a map area and then try to relate these variations to geologic features in the subsurface. Lacking a controlled source, such surveys are usually environmentally unobjectionable.

At a comparatively low cost, airborne potential field surveys can provide coverage of large areas. Allowing quick regional coverage, even gravity surveys can now be recorded from an aircraft with airly high reliability.

In Canada, digital regional gravity and magnetic data are available at zero cost from federal government agencies. Local and detailed surveys are acquired by exploration companies.

Because many college programs tend to overemphasize seismic as almost the only geophysical tool for oil exploration, other methods are sometimes overlooked by explorationists and managers. Where useful gravity and magnetic data are disregarded, risk reduction is incomplete, and the results of exploration programs are less reliable.

What anomalies mean

The physical rock property that links gravity anomalies to rock composition is density. The rock property that links magnetic anomalies to rock composition is total magnetization. Thus, each potential-field method valuable provides its own picture of the subsurface.

Density is scalar, but magnetization is a vector total of a vast and commonly unpredictable variety of remanent and induced magnetizations. Unlike density, magnetization can depend on very slight variations in the occurrence and distribution of particular minerals, which may have little relation to the overall lithology.

A geophysical anomaly is the difference between the observed (measured) geophysical field value and the value that would be observed at the same location if the Earth were more uniform. Nonuniformities in the physical properties of rocks give rise to geophysical anomalies.

Being responsive to lateral variations in rock properties, gravity and magnetic methods are best suited for detecting steep discontinuities such as faults. Seismic methods, by contrast, are best for detecting vertical rock variations and low-angle discontinuities such as layer boundaries.

The gravity field is simple, unipolar and almost perfectly vertical. The geomagnetic field is complicated: It has two or more poles, and it is commonly strongly nonvertical. Besides, it changes all the time, necessitating frequent updates by government agencies.

Gravity lows (negative anomalies) occur where rocks in the subsurface have a comparatively low density, which reduces their downward gravitational pull. Where the rock density is relatively high, the gravitational pull is increased, and a gravity high (positive anomaly) occurs.

Magnetic anomalies are more complex because the magnetic field and rock magnetization are both complicated. With a nonvertical dipolar field, a single rock-made anomaly source can be deceptively associated with a pair of apparent anomalies: a high and a low side by side.

Gravity and magnetic surveys should be designed purposefully to resolve the specific kind of anomalies that are expected from geologic targets of interest in a particular study.

Gravity and magnetic surveys should be designed purposefully to resolve the specific kind of anomalies that are expected from geologic targets of interest in a particular study. If a survey is too tight, money is wasted on redundant coverage. If a survey is too sparse, the desirable anomalies are undersampled and not delineated sufficiently. The idea is to design the sparsest and smallest, hence cheapest, survey that would resolve all the expected desirable anomalies.

Examples of exploration use

In the platformal Phanerozoic Alberta and Williston basins, most big magnetic and gravity anomalies are associated with ductile structures and rock composition variations in the crystalline basement inherited from orogenic events in the Precambrian. Such ductile ancient structures were fairly seldom reactivated, and they had relatively little influence on the Phanerozoic basins above.

More important are the later brittle basement faults and fractures, whose offset can be as little as a few meters, sometimes below seismic resolution.

Such brittle faults had a variety of direct and indirect influences on many intervals in the Phanerozoic sedimentary cover. They are commonly associated with subtle gravity and magnetic lineaments, some of which cut across the regional pattern of major anomalies. To help delineate fault networks, researchers created a regional gravity and magnetic atlas of the southern and central part of the Alberta Basin.

A gravity or magnetic lineament can be a gradient zone, linear break in the anomaly pattern, straight anomaly or even an alignment of separate local anomalies. Long lineaments are more likely to be associated with faults than short ones, especially if they occur in swarms or are a part of a regional pattern.

The best data processing methods are simple and intuitive so that derivative maps and anomalies are easy to relate to their precursors in the raw data.

Gravity and magnetic data can be processed specifically to highlight subtle lineaments (Figure 1). Particularly useful processing methods tend to be first and second horizontal and vertical derivatives, third-order residuals, automatic gain control, total gradient (analytic signal) and shaded-relief maps (shadowgrams). Wavelength filtering has a major pitfall in that Gibbs ringing can produce lineament-like artifacts, so it is best avoided.

FIGURE 1. This regional horizontal-gradient magnetic map of central and southern Alberta shows selected lineaments highlighted as straight white lines (after Lyatsky et al., 2005). (Source: Lyatsky Geoscience Research & Consulting Ltd.)

To help identify faults, gravity and magnetic lineaments should be compared with topographic and drainage lineaments. Seismic data and geological studies can help to determine if suspected faults had an influence on any particular play interval.

In horst and graben basins such as the offshore Queen Charlotte Basin on the west coast of British Columbia, the first step is to examine geological information from the surrounding areas on land and from drillholes in the basin. The pattern of raised and lowered crustal blocks in and around the basin can be determined from geologic field mapping and from a combination of seismic and gravity data.

Magnetic data (Figure 2) in the Queen Charlotte Basin were used to further delineate the networks of local and regional faults. Seismic data in this basin suffer from an uneven maximum depth of signal penetration due to the presence of numerous volcanic stringers. On land and offshore magnetic data were instrumental in the delineation of extrusive and intrusive igneous rocks, which was crucial for understanding the patterns of organic maturation.

FIGURE 2. In this horizontal-gradient magnetic vector map of the Queen Charlotte Islands and Hecate Strait, British Columbia, the numbered heavy black arrows indicate magnetic lineaments. Light thin lines indicate the magnetic horizontal gradient, with length proportional to the gradient magnitude and pointing “downhill.” (Source: Lyatsky Geoscience Research & Consulting Ltd.)

Teaching of gravity and magnetic methods

The relatively low priority given to potential-field methods in many oil-oriented college programs impoverishes students and their employers. Where gravity and magnetics courses exist, too often they focus—with intimidatingly advanced mathematics—on the physics of potential fields at the expense of exploration applications, survey design and methods of geological interpretation.

Too many gravity and magnetics textbooks are also very mathematical (with a superb exception of Nettleton, 1971). Too little tends to be said about the relationships between anomalies and variations in rock composition, which is the key to geological interpretation.

Misleadingly, numerical inversions of potential fields data are sometimes presented as interpretations. However, mathematics is abstract. Interpretation is essentially geological, with geophysical data used to provide geological information.

When geologists, seismologists and potential fields experts are too narrowly specialized, they do not talk to each other enough. The result is commonly disregard of valuable gravity and magnetic information. Alternatively, interpretations are too numerical to be useful if geological considerations are ignored.

Gravity and magnetics experts in oil exploration should talk less in an echo chamber among themselves. They should learn to think more like their clients, who tend to be geologists and seismologists. Their work should be presented from first principles, with minimum mathematics and with maximum geological consideration. Only then can interdisciplinary walls be brought down and exploration managers can vividly see the essential practical utility of gravity and magnetic methods.

Source : www.epmag.com

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17.6 million Americans live near oil and gas wells and fracking

Those who live within 1 Km from active wells are more at risk of cardiac and neurological problems, cancer and malformation at birth

Physicians, Scientists and Engineers (Why) for Healthy Energy is a non-profit research institute that provides scientific and technical information based on the health, environmental and climatic impacts of energy production and use and is now published on Environmental Perspectives Health  the study "Towards Consistent Methodology to Quantify Populations in Proximity in Oil and Gas Development: A National Spatial Analysis and Review of Environmental and Climate Dimensions of Energy Production and Use," which shows that "approximately 17.6 million Americans live within a kilometer of an active oil or gas well ". The study, conducted with researchers at the California-Berkley University and Havey Mudd Collegs, is the first US census on the number of people living near petroleum and gas production sites, both traditional and fracking wells .

The Why recall that previous studies "have found that active oil and gas production degrades the quality of air, surface water and groundwater; Contaminate soil and increase exposure to noise and light pollution. According to separate studies, when people live within one kilometer of these activities, they have a greater risk of being hospitalized for numerous medical problems, including heart and neurological problems, tumors, and increased incidence and severity of asthma. Neighborhood proximity to these activities has also been associated with birth problems, including premature birth, lower birth weight, neural tube defects, and congenital heart defects.

Yet so far, only a few studies have been published to quantify populations living near petroleum and gas stations and these studies did not link pollutant emissions to certain types of oil and gas production activities.

The study's main author, Eliza Czolowski, explains, "Our study was designed specifically to determine how many Americans saw increased health risks from potential exposure to pollutants emitted by petroleum and gas activities."

In addition to computing the total population of the Usa exposed, researchers analyzed exposure in the various US states by highlighting those with particularly high percentages of population living close to active wells. West Virginia was the most risky state, with 50% of residents living near an active oil or gas well. Right after Oklahoma, it's 47%. La Czolowski. It points out that "When a member on two of a population is potentially exposed to a health risk, this becomes a concern for public health."

Nearly a quarter of Ohioans - 24% - live alongside active wells. MA is the Texas true to most people at risk: 4.5 million. Near live ponds they live 1.4 million children up to 5 years old, a subgroup very vulnerable to environmental exposures

The researchers examined both hydraulic fracturing techniques (fracking) and traditional wells, and Czolowski noted that "Despite the differences in conventional and non-conventional oil production techniques, the health risks can be very similar. Many atmospheric pollutants, including benzene, formaldehyde and particulate matter, are emitted from both conventional and non-conventional activities because they are co-produced with oil and gas, not specifically because a well is fractured hydraulically. Also the emissions of atmospheric pollutants from associated activities, such as drilling wells and truck traffic, are not specific to hydraulic fracturing. "

The researchers point out that some of the data they requested were not available and therefore encourage further studies that follow similarly stringent methodologies, focusing in particular on public health, and taking into ACCOUNT variables excluded from their study, such as population density and activities.

The study concludes that "Given the large number of individuals and the large percentage of populations potentially exposed to pollutants emitted by petroleum and gas activities, protection standards and policies should be considered. Health protection policies may include minimum distances between these activities and places where they live, play and study people, as well as a widespread deployment of the best available technologies to reduce air pollution. "

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Steerable Downhole Mud Motor - Directional Drilling

Steerable Downhole Mud Motor (SDMM) commonly referred to as Mud Motor or Drilling Motor acts much as a positive displacement motor which provides additional rpm to the drill bit from the flow of drilling fluid (mud).

This drilling motor is far different from an electrical motor in it's working principle and operation.

(A lot of people get confused initially)

Since its introduction, the positive displacement motor has undergone revolutionary changes and improvements. Downhole drilling motors have proven to be successful in the most rigorous of drilling environments. From the time of its inceptions, the mud motors have gone extensive improvements that has enhanced its performance, operational and economical reliability. 

Today there are numerous players in the industry providing mud motors for different operational requirements. Few to name are National Oil Varco (NOV), Schlumberger, Halliburton, Baker Hughes, Weatherford, Cavo, Bico, Jaguar, APS, etc. Different mud motors provided by different companies vary a little from each other but, there basic operating principle remains the same. 

Mud Motors have extensively wide range of applications and few of them are listed below:

Conventional Directional Drilling

Side-Tracking

Performance Drilling

Short/Medium/Ultra-short Radius Wells

Air/Foam or Under-balanced Drilling 

ERD Wells

HP/HT Wells

Coiled Tubing Drilling

Vertical Drilling

Casing Drilling

Milling

Coring

Slim Hole Drilling

Working Principle

Mud motors converts the flow energy of drilling fluid (mud) in rotational motion that's utilized in rotating drill bits at a much higher rpm. 

It's imperative that flow rate can be used to control the rpm of the drill bit as per operational requirements. Flow rates for muds are provided by the mud pumps.

Bit RPM = {Flow rate (in GPM) x RPG (Revolutions Per Gallon)} + Rotary RPM 

Note: 

RPG is defined as the revolutions made by bit box and in turn bit, when one gallon of mud flows through it & is mentioned by the manufacturer for each type of SDMM.

While sliding rotary rpm will be zero.

Parts of SDMM:

Simple classification of SDMM parts can be categorized as: 

Top Sub Options

Power Section

Drive Shaft Assembly

Adjustable Bent Housing Assembly

Bearing Assembly

Bit Box

Top Sub options

Top Sub: 

Top sub is simply a cross over housing at the top end of the motor. The lower connection uses a thread that connects to the upper box of the stator housing.

Dump Sub:

It contains a Dump Valve Assembly. This allows the mud to fill or drain from the drill string while tripping.

To avoid the ingress of solids from the annulus when the pumps are off, it’s normal to run a float sub as close to the motor as possible.

The motor will function perfectly without a dump valve - It can be laid down and replaced by a sub having the same connections or run with the ports blanked-off. 

Failure of the dump valve assembly can cause sometimes serious troubles.

Motor Catch & Rotor Catch Top Subs:

The rotor catch system is designed to retrieve the motor in case of a housing fracture. It will retrieve the motor from the upper stator box connection down to the drill bit. The motor catch system has the additional feature of an integral catch flange within the top sub. It will retrieve the motor from the top sub down to the drill bit.

Power Section

Positive Displacement Motors (commonly called a PDM) are reverse applications of a Moineau pump or screw pump. 

It mainly consists of Rotor & Stator.  

Rotor is chrome-plated alloy steel of spiral-helix shape. 

Stator is a hollow steel housing, lined with a molded-in-place elastomer rubber compound. 

A spiral-shaped cavity is produced in the stator during manufacturing. The rotor is produced with matching lobe profile and similar helical pitch to the stator, but with one lobe less. The rotor can therefore be matched to and inserted inside the stator. When assembled, the rotor and stator form a continuous seal along their matching contact points. Fluid is pumped into the motor’s progressive cavities. The force of the fluid movement causes the shaft to rotate within the stator. Thus, it is a positive displacement motor. The rotational force is then transmitted through the connecting rod and drive shaft to the bit.

  

Stage is the distance measured parallel to the axis between two corresponding points of the same spiral lobe. This distance is commonly referred to as the lead of the stator. A slight interference fit between rotor OD and stator ID controls motor power. 

Mud motors are divided into slow-speed, medium-speed and high-speed types. This is done by changing the pitch of the motor stages, by the number of "lobes" and resultant cavities of the stator. 

The greater the number of lobes, the higher the motor torque and the lower the output RPM. 

Increasing the flow rate through a given power section directly increases the output speed. To increase the output speed of a power section without changing the flow rate, the cavity size is changed. A high speed power section will require a larger fluid inlet area (cavity) to allow more fluid throughput into the cavity.

The torque generated by the power section is proportional to the differential pressure applied across the power section and is independent of fluid flow. Generally, the more weight applied to the bit, the higher the torque needed to keep the bit turning, so the higher the differential pressure across the Power Section.

The maximum recommended differential pressure is limited by the stator elastomer. If pressure increases beyond the limits of the elastomer, the stator elastomer will deform, breaking the cavity seal so the mud flow leaks past the rotor and rotation stops – this is commonly known as a stalled motor.

Drive Shaft Assembly

The drive shaft assembly converts the eccentric motion of the rotor into concentric rotation for the bearing assembly via a connecting rod attached to the lower end of the rotor. It transmits the torque and rotational speed from the rotor to the drive shaft and bit. Universal joints convert the eccentric motion of the rotor into concentric motion at the drive shaft. 

It also accommodates any angle set on the adjustable bent housing (or fixed bend housing) and carries the thrust load from the rotor caused by the pressure drop across the power section.

Adjustable Bent Housing

ABH connects stator to the bearing assembly and also houses drive shaft assembly. It has a field adjustable angle-setting to produce a wide range of build rates.

Angle setting may be set to zero for vertical drilling or may be set to any other angle setting as desired. Once the angle is set for the mud motor, it can't be changed when it's down hole and has to be pulled out of the hole to change the angle-setting.

Higher rotary rpm could be used at low angle-setting as compared to a high angle-setting.

Drilling at a higher rotary rpm provides a drill bit with more torsional force provided by the entire rotating drill string as compared to the torsional force provided alone by the mud motor.

(That's the reason why ROP in rotary mode > ROP in sliding mode)

Bearing Assembly

The drive shaft assembly is supported within the bearing housing by radial and axial thrust bearings. It transmits the rotation of the drive shaft assembly to the drill bit and the compressive thrust load created by the weight of the collars and drill string to the rotating bit box & supports the radial and bending loads developed while directional drilling.  

It also carries the tensile off-bottom thrust load produced by the pressure drops across the rotor and the drill bit, as well as any load caused during back reaming. The high capacity radial bearings readily withstand side loads caused by drilling with a deflection device or uneven cutting action along the drill bit periphery. The tungsten carbide radial bearings and angular contact bearing section supports the radial loads along the full length of the bearing assembly, creating a very stiff, strong assembly

Types of Bearing Assembly-

Mud Lubricated Bearing Assembly

Oil Sealed Bearing Assembly

Mud Lubricated Bearing Assembly regulate the flow of mud through the bearing assembly. This diverted mud (usually 4 - 10%) is used to cool and lubricate the shaft, radial and thrust bearings. It exits to the annulus directly above the bit sub. The exact percentage of mud diverted is determined by the condition of the bearings and the pressure drop across the bit. Mud lubricated bearing assemblies can be used in the hottest holes with the lowest aniline point drilling fluids, as there are no elastomeric seals.

Oil Sealed Bearing Assembly is an alternative to the mud-lubricated bearing. A sealed bearing would be recommended where corrosive muds are used, where a lot of LCM of various sizes is pumped or where there is a requirement for a very low pressure drop across the bit (Pbit).

Bit Sub

At Bit sub the drill bit is make up with the motor and it's the only moving external part of the motor.

  

Note: 

In addition to above, different manufacturers can have more or less parts.

The operating conditions and parameters for the mud motors may vary for different manufacturers.

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Oil Exploration

Crude oil is usually located deep below the earth's surface, without any visible traces of being present.

In the early years of the oil industry, one could easily find small amounts of oil in the vicinity of the oil urinating drilling. "Oil Lakes" are small amounts of oil that come up on the surface or in water.

However, a well drilling is very expensive; Therefore, alternative methods have been sought in order to locate oil. Today, geologists determined using a range of techniques where oil could be found. They make use of include seismic and visual observation techniques to determine the geological formations could contain oil.

• Seismic surveys

this case a small amount of underground explosive is detonated. In addition, to be sensitive instruments used which register the shock waves moving across the ground and which are reflected by rock walls. On the basis of the speed and direction of the waves geologists can identify the type of rock formations, and to detect the types of which are known to oil or hydrocarbons (such as gas) may contain.

• Vibro-seismic survey

, with special vibrating trucks are used, which is a controlled signal to submit the bottom. Although this method is more complicated, it is often used in places where explosives can not be used for practical reasons.

• Geophysical research

, this method is used to measure the thickness of sediment and in order to map out the shape of the structures within the sediment. In this way, often underground structures could be located in the last 30 years where oil had gathered.

• Research based on aerial photographs

on the basis of aerial photos, maps can be established in which the main geological properties are shown of an area. The photos are also used to determine oil field pipelines and infrastructure very closely. This information is of great value for planning seismic surveys and other projects.

• Surface Research

Here, specific localized areas on the ground and it is determined their height. One of the tools used therewith, is a theodolite, which is equipped with a telescope that measurement angles horizontally and vertically.

• Gravity investigation

In this method, there is used a highly sensitive gravimeter, which is analyzed to gravity variations. These variations may indeed indicate hidden geological structures. The study is usually performed in an early stage of exploration. The researchers thereby identify areas that may be potentially interesting. At these zones is then carried out, a more detailed seismic survey.

Drilling for oil

When certain areas of potential interest are labeled, are drills used to dig wells. Seismic research shows that the best places to look for oil. In this way, the risk of finding dry wells ( "dry hole") is limited. They contain no oil.

A drill is guided straight into the ground. If the rig can not be drawn directly on the surface, it is placed next to it and is drilled at an angle. The horizontal drilling technology is used to drill into the portion of the source which horizontally through the oil (the "output section") passes along the path from the oil reservoir.

Oil Transport

Crude oil is transported by pipeline from the drilling rig to tank farms. Since the oil is stored in huge tanks. The crude oil is then transported by pipeline to a local refinery or an oil tanker to an overseas refinery.

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