Questforoil Studenttasks Uk

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STUDENT TASKSQuest for Oil

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1. Game tasks .................................................................................................................................................................................................................................................... 3

2. Themed tasks2.1 Theme: Seismology (tasks 1-6) ....................................................................................................................................................................................................... 52.2 Theme: Seismic (tasks 7-10)....................................................................... ...................................................................................................................................... 52.3 Theme: Oil wells (tasks 11-13)......................................................................................................................................................................................................... 62.4 Theme Oil production (tasks 14-16)........................................................ .................................................................................................................................... 7

3. Game tasks/Experiments3.1 Seismic investigation of substrata (GeoCase equipment) ............................................................................................................................................... 83.2 My Own Little Oil Field .......................................................................................................................................................................................................................... 113.3 Permeability ................................................................................................................................................................................................................................................. 143.4 Migration of oil in sand .......................................................................................................................................................................................................................... 163.5 Determining rock density ................................................................................................................................................................................................................... 173.6 The content of water and organic material in soil ............................................................................................................................................................. 19

A. ContentsStudent tasks

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The Quest for Oil-related questions that can be answered quickly are shown below.

1. Game tasksStudent tasks

Task 1Oil is made up of:

A) Decomposed biological material from dead fish, plants, etc.

B) A mixture of dissolved particles of stone and rock

broken down by atmospheric pressure over millions of years

C) Calcite crystals and coccoliths, condensed by passive

exposure to UVB solar radiation over billions of years

Task 2What is the temperature at 3.4 km below the earths surface?

A) 180-240 C B) 120-180 C C) 60-120 C

Task 3Which one of these rocks does not contain oil?

A) Limestone B) Shale C) Igneous rock

Task 4When under water, oil always moves

A) Upwards

B) Downwards

C) Oil is always static

Task 5Is the porosity of shale high, medium or low?

A) High B) Medium C) Low

Task 6To pump up oil from the sea floor, a mixture of:

and

are used.

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Task 7Explain why some rocks contain more oil than others.

Task 8Explain why it is important to closely monitor the drilling speed when drilling for oil.

Task 9Explain why it is not always financially feasible to buy a brand-new offshore oil rig:

Task 10Explain why it is not always financially feasible to buy a pipeline.

Task 11Three different types of offshore drilling rig are used in Quest for Oil. Name them.

1)

2)

3)

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2. Themed tasksStudent tasks

2.1 Theme: Sedimentology

Task 1Are the following materials sediments? Justify your answers.

1) Beach sand2) Rock salt3) Peat

Task 2Reservoir rocks: Limestone and sandstone are common reservoir rocks. Explain why in more detail, defining the concepts of permeability and porosity at the same time.

Task 3Is it possible to artificially increase the porosity and permeability of reservoir rocks? Explain your answer.

Task 4 Would you primarilly use porosity or permeability to calculate the oil reserves in your oil field? Why?

Task 5Explain why it is currently not possible to retrieve 60% of the oil reserves found in the North Sea?

1) Geological reasons2) Technical reasons

Explain.

Task 6Describe and explain at least two different methods that can be used to enhance the recovery of oil from an oil field.

2.2 Theme: Seismology

Task 7How will a salt diapir appear on a seismogram? Draw a sketch or insert an image/figure into your reply and explain:

1) How is rock salt formed?2) Why and how does salt move upwards?3) Why is salt an excellent seal rock?

Themed tasks are assignments related to oil exploration.

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Task 8What does a fault trap look like on a seismogram? Sketch or insert an image into your reply and explain.

1) How are faults created?2) How are oil traps created along faults?3) What are oil traps at faults called?

Task 9How is it seismically possible to see direct signs of oil/gas? Explain:

1) How does the presence of gas affect the signal?2) Explain and sketch how to interpret a fault trap on a seismogram (2D)?

Task 10Explain the different seismic technologies that are used:

1) At sea2) On land3) Explain the sources of signal noise in the various

technologies.

2.3 Theme: Oil wells

Task 11Drilling for oil and gas is expensive. There is a one in five chance of finding oil/gas.

Which "checkpoints" should be included in a drilling programme? Explain why.

Task 12Describe the sequence of drilling events leading up to a blowout, including the following in your description:

1) Explain what technically constitutes a blowout.2) How is pressure usually controlled in the well?3) Briefly describe the set of problems around the

Deepwater Horizon disaster.

Task 13Drilling rigs.

1) Which rigs are the most common in the North Sea and why?

2) Which type of rig is used in deep water (max. depth: 4,000 m)?3) Why do oil companies usually lease rigs instead

of owning them?

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2.4 Theme: "Oil production

Task 14Production technology - answer the questions below:

1) What is involved in field expansion?2) When is the production of oil completed?3) Where is Denmarks offshore industry located and

what does it involve?

Task 15Describe environmental problems relating to offshore oil production, citing examples of:

1) Environmental problems "on site"?2) Environmental problems in transit?3) Environmental problems in the Arctic?

Task 16Crude oil comes in different qualities. Explain:

1) What is the difference between "light" and "heavy" oil?2) How does the quality of crude oil affect its market

price?3) What is the quality of "Danish oil"?

DRILLSHIPOperates at water

depths up to 12,000 ft.

SEMI-SUBMERSIBLEOperates at water depths

up to 10,000 ft.

JACK-UP RIGOperates at water

depths up to 500 ft.

DRILLING BARGEOperates in

shallow waters

LANDRIG

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Project weeks or project days provide a good opportunity for subsequent follow-up with an experiment.

Note: These tasks usually require materials that have to be obtained in advance by the instructor. See under Materials in the task concerned for an itemised list of materials.

START THE SEISMIC MEASUREMENTS.

3. Game tasks/ExperimentsStudent tasks

3.1 Seismic investigation of substrata (GeoCase equipment)

PurposeTo gain better insight into how to study substrata in relation to oil exploration, geological survey of substrata and earthquake waves.

Equipment Tape measure Pencil and paper 4 geophones Geophone sensor (HS4 unit) Aluminium slide plate with permanently attached cable Large hammer with permanently attached cable Ear protectors

IMPORTANT:Take good care of the equipment, as it is neither waterproof nor rainproof.

Experiment set-up

Task 1Select a suitably flat location, e.g. a field or football pitch. Position the geophones by carefully inserting the tip into the ground (THEY ARE TOO FRAGILE TO BE PUSHED INTO THE GROUND WITH YOUR FOOT!). Place the geophones along a straight line in the numbered sequence at intervals of three metres.

Task 2Connect the 4 numbered geophones to the 4 numbered sockets on the front of the HS4 unit (red to red and black to black).

Task 3Connect the white cable with the serial plug to the back of the HS4 unit, then connect the plug from the hammer to one of the outlets on the white cable. Connect the other plug on the white cable to the aluminium slide plate. After this, connect the HS4 unit to the USB port on the computer.

Task 4Start the Handyscope HS4 program, if this has not already been done. Click "Scope" in the small box that appears. When the program starts, select "File" and click Restore instrument setting... Find the file named Basisopstning til seismik.set on the desktop.

Task 5After this, you must selcted the calculation of the average of 4 impacts. Enter the Measure menu, select Perform averaging of, and then 4 measurements.

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As only two geophones are used in the first few exercises, "remove" the extra geophones (3 and 4) by clicking the "eyes" at the bottom of the screen (the geophones will con-tinue to measure but will not be viewable on the screen). When all four geophones have to be used, just click the geophones again to render all measurements visible. 1. Place two geophones next to one another at a distance

of 2m from the metal plate. Hit the metal plate with the hammer. What is the duration of the two waves recorded by the geophones? The seismic wave shapes recorded by the two geophones should be (almost) identical. Are they?

2. Move one geophone 2m further away from the metal

plate and hit it again. What is the difference in the duration registered by the two geophones? Estimate the seismic velocity in the sedimentary layer beneath the geophones. What happened to the amplitude of the wave registered by the geophone furthest from the metal plate? Why did this occur?

3. Position one geophone next to the metal plate. Position the other geophone 0.5m from the metal plate. Hit the plate again and note the durations registered by these two geophones.

Move the geophone furthest from the plate to a distance of 10m from the metal plate in steps of 0.5m. Measure the duration of the seismic response at each interval out to the furthest position.

4. Use all four geophones in this exercise. Find the seismic velocity in the bedrock. If there are

two sediminentary layers, there will be two velocities. If there are two sedimentary layers, determine the

depth of the second layer.

Processing the resultsPlot the time of the wave arrival as a function of the distance for the seismic source. If there are two layers, the graph will resemble Figure 1, otherwise the graph will be a straight line.

The time it takes for a wave to move through homogenous material is linear.

In the graph in Figure 1, we can see that the points are not linear. On the other hand, we can make two lines (red lines 1 and 2). This means that two different layers are present. Line 2 is the refracted waves duration curve. Xc is the shortest distance at which the refracted wave can be measured and is called the critical distance.

Figure 1

Figure1: An example of times plotted for a seismic measurement. xc shows where line 2 starts. Line 2 should be a broken line from xc until x=0.

ti

00

XC

Line 1

Line 2

Geophone 5

Geophone 3

Geophone 2

Distance (m)

Geophone 1

Geophone 4

Tim

e (s

ec)

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If your line 1 does not pass through (0.0) in the graph, then there is a delay in the set-up of the measuring equipment. This is not unusual and can be rectified by making a paral-lel displacement of the entire graph so that line 1 passes through (0.0). In practice, this will only mean that times read from (0.0) up to where line 1 transects the y axis must be deducted from all times registered on the graphs y axis.

The distance (depth) to the stratum boundary between the two layers can be determined using the formula:

In which:z = depth1 = velocity in the upper stratumti = transection of the time axis for the extrapolated line 2O = critical angle of refraction 1 can be found using the inclination of Line 1, 1. v1 is calculated as 1/1. v2 can be similarly determined using the inclination coefficient for line 2, 2: v2=1/2. c can then be determined using the law of refraction: sin c =v1/v2 ti is read on the graph. 5. Describe which geological material(s) will yield the

velocities measured. 6. Assess the seismic signals main period by counting

wave tops (or valleys) across a well-defined time interval. Calculate the signals main frequency and use the relation V to calculate the signals wavelength in the strata you have found.

Tidying upPack up the equipment and carefully roll up the cables.

1

2z= v

1t

1/cosO

c

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Seismic profiles

Seismic profiles

NB: the X axis is in feet and the Y axis is in metres

3.2 My Own Little Oil Field

Prerequisites

1. We have two seismic profiles through the reservoir (see the figure).

2. The MOLO-1 well hit the top of the reservoir at a depth of XXXX feet.

3. The MOLO-1 well found the oil/water transition zone (bottom of the reservoir) at a depth of XXXX feet.

4. The average porosity ( ) is set at 0.XXX (xx.x vol%)

5. The reservoir rock includes another rock without reservoir characteristics The net/gross ratio (N/G) is 0.90 (90%v/v)

6. The average water saturation (Sw) in the reservoir is 0.XX (XXvol.%)

7. The oil formation volume factor (FVF, reduction in volume of oil resulting from the gas content for adjusting the reservoirs pressure and temperature to atmospheric conditions) is set at 1.2.

8. The recovery factor (RF) is set at 0.25 (25% of the stock tank oil initially in place (STOIIP) is thus retrie-ved at the surface).

Your task is now to:

1. Calculate the formations volume, (GRV = Gross Rock Volume)

1. Calculate the volume of oil that can be recovered from the reservoir (STOIIP)

2. Calculate the reserves.

MOLO-1 well

feet

5,700

6,000

6,300

6,600

6,900

7,200

7,500

7,800

0 1,000 3,000 4,000 5,000 6,000 m2,000

Top of reservoir

Surface of contact between oil and water (transition zone)

West East

NorthMOLO-1 well

South

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MAO-1 well

NB: the X axis is in feet and the Y axis is in metres

A probe measurement yielded the profile shown for the wells porosity and carbon-hydride saturation.

Approx. 180foot chalk-oil reservoirh 60m

GRapi0 150

TVDSSFT7700 6700

LLDOHMM0.2 200

LLSOHMM0.2 200

MSFLOHMM0.2 200

TNPHCFCF0.6 0

DRHOG/C30.75 -0.25

RHOBG/C31.7 2.7

DTCO1US/F140 40

DEPTHFT

PHI-CFCF0.5 0

BVW 0.5 0

VGAS-CFCF0.5 0

VOIL-CFCF0.5 0

SW-CFCF1 0

VSHCFCF0 1

PHI-CFCF1 0

0 VSH

VSH PHI-

TVDSSFT

Lista Fm

North Sea MarlTop D1

GOC

Top D2A

Top D2B

MhM1A

M1b1M1b2M1b3M1b4M1b5M1b7

M1b8

M2

M3

OWC

M4

6950

7000

7050

7100

7150

7200

7250

7300

7350

6800

6900

7000

7100

7200

GRapi0 150

TVDSSFT7700 6700

LLDOHMM0.2 200

LLSOHMM0.2 200

MSFLOHMM0.2 200

TNPHCFCF0.6 0

DRHOG/C30.75 -0.25

RHOBG/C31.7 2.7

DTCO1US/F140 40

DEPTHFT

PHI-CFCF0.5 0

BVW 0.5 0

VGAS-CFCF0.5 0

VOIL-CFCF0.5 0

SW-CFCF1 0

VSHCFCF0 1

PHI-CFCF1 0

0 VSH

VSH PHI-

TVDSSFT

Lista Fm

North Sea MarlTop D1

GOC

Top D2A

Top D2B

MhM1A

M1b1M1b2M1b3M1b4M1b5M1b7

M1b8

M2

M3

OWC

M4

6950

7000

7050

7100

7150

7200

7250

7300

7350

6800

6900

7000

7100

7200

Task 1 The shape of the reservoir resembles a spherical cap.

The gross rock volume (GRV) is the volume of a spherical cap with a height of h and radius of. h is found using the probe measurement from the wellis determined on the basis of the seismogram.Calculate GRV by inserting into term (the number could be very big!)

GRV = 1/6h(3+h)

feet

5,700

6,000

6,300

6,600

6,900

7,200

7,500

7,800

0 1,000 3,000 4,000 5,000 6,000 m2,000

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Task 2

Gross rock volume (GRV) net-gross ratio (N/G) porosity ( ) oil saturation (S

oil) =1water saturation (S

w)

oil formation volume factor (FVF, here set at1.2)

Calculate STOIIP using this expression (the unit at this stage is in m):

STOIIP = GRV N/G Soil / FVF

Task 3

We convert STOIIP (m) into STOIIP (million bbls) by inserting in this term:

STOIIPmillion bbls

= STOIIPm

6.29:1,000,000

Finally, calculate the reserves based on a recovery factor (RF) of 0.25(=25%):

reserves = STOIIPmillion bbls

RF

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3.3 Permeability

PurposeThe purpose of this experiment is to show how a soils permeability and field capacity differ depending on the type of soil concerned.

TheorySoil is made up of three components:

1. Hard components, i.e. minerals and organic matter

2. Water with dissolved substances

3. Air with a slightly different composition than atmo-spheric air.

Voids in the soil can contain both air and water. The water and air volume is jointly referred to as soils pore volume. The ratio between pore volume and the soils hard components indicates the soils porosity (measured in %). Soil with large voids is called porous.

Variations in the relative volumes of these three com-ponents means that the soils permeability - i.e. to water - varies. The velocity at which water leaches down to groundwater deposits is indicated in mm/min. The velocity of water is highest where soil voids are biggest.

Similarly, variations in the three components affect the soils field capacity, i.e. the ability of the soil to retain water.

Porosity

Large, round and uniformly sized grains create many voids between them. Hydrau-lic conductivity is high through this type of soil.

High permeability.

Smaller grains mean smaller voids between the grains.

Lower permeability.

If a soils grains vary in size, e.g. as is the case in topsoil, the small grains will fill out the air cavities, and water will not flow as easily through the soil.

Low permeability.

Clay adheres into small flat grains through which it is almost impossible for water to penetrate. Clay can form a water-stopping layer.

Between zero and almost zero permeability.

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HypothesisWrite a well-reasoned hypothesis about the expected cor-relation between porosity, permeability and field capacity for your sand or soil mixture.

MaterialsFunnel, filter paper, 250-300 ml measuring cylinder, 300 ml conical flask, weighing scales, fine sand, medium sand, coarse gravel, water and a clock.

ProcedureWeigh a total of 200 g of each grain size on a piece of filter paper.The experiment can be varied by mixing different grain sizes and/or by using fertile garden soil for the experiment.

Place the funnel in the plastic measuring cylinder.Place the filter paper holding the weighed volume in the funnel. Pour 300 ml water over the sample. Pour slowly into the middle of the funnel.

Note the starting time when the first drop drips into the measuring cylinder and the ending time for the last drop. Read the volume of water in the measuring cylinder.

Calculate the amount of water retained in the sample. Repeat this procedure for the other two grain sizes.

ResultsCalculate permeability.Process the results into a column graph for each of the three samples.

DiscussionExplain the results using the terms porosity, permeability and field capacity.

Gravel Sand Silt Clay

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3.4 Migration of oil in sand

PurposeTo perform simple experiments to learn more about how oil migrates through sand.

TheoryOil and gas are formed in bedrock rich in organic material. In order for oil and gas to be able to collect in an oil trap that is profitable to exploit, the oil/gas must first migrate, i.e. wander, through permeable layers before ultimately being "trapped" under an impermeable layer, whose shape forms an oil trap.

Conclusion

Hypothesis

How do you expect oil located under a layer of sand to move?

And how will a layer of clay affect the migration of the oil? Justify your hypothesis.

MaterialsSand, beaker or glass, water, vegetable oil (mixed with colouring and a little washing-up liquid), clay.

ProcedurePour 1-2 cm of oil into a glass.Then pour sand on top of this, covering the oil and forming a "pure" layer of sand.Finally, carefully pour 2-3 cm of water into the glass.

Set the oil aside for 20-30 minutes and observe it in the meantime. Leave the sample alone until the next module and see whether more oil has migrated.

Discuss the results and a new hypothesis about the formation of oil traps. Was your hypothesis correct? If not, revise the hypothesis. Did you include the solubility of the colouring in your hypothesis?

Next, based on the results, set up a new experiment to show how an oil trap works. You will also be issued with clay in addition to the materials you have already.

Prerequisites for deposits of oil and gas

Prerequisites for deposits of oil and gas

Trap

Source rockReservoir

Clay Sand Organic material

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3.5 Determining rock density

PurposeTo perform experiments and measurements concerning the density of density rocks.

MaterialsVarious rocksWeighing scalesSmall string bags (e.g. like the bags used for packing bird suet)Spring balance (one per group)Large (0.51 l) beakerWater.

TheoryDensity is defined as mass per unit volume, often indicated as g/cm3. If the substance being measured has a mea-sureable shape (e.g. cubical or spherical), then it is possible to measure and calculate its volume. But the rock samples we are to measure are so irregularly shaped that it would be hopeless to measure them and calculate their volume.

Therefore, this experiment uses Archimedes principle, which states that the upward buoyant force which is exer-ted on a body immersed in a fluid, whether fully or partly submerged, is equal to the weight of the fluid that the body displaces. When we fully submerge a stone, the grams of water displaced will therefore equal the stones volume, as the density of water is 1 g/cm3 (slightly depending on the temperture, but which is insignificant in this experiment).

The spring balance measures force in N. This must be converted into grams by multiplying by 1,000 and dividing by 9.82, as 1 N = 1 kg x m/s2, and the gravitational accele-ration is 9.82 m/s2.

ProcedureThe class is divided into four different groups, each of which is issued with a number of identified sample rocks.

1. Pick up the samples one by one and assess their density. Try to see if your group can agree on ranking the samples by density (from lowest to highest). Use this as your hypothesis.

Lowest Highest

NB! Geologists often use the concepts "light" and "heavy" when they actually mean "low" or "high" density. Heavy rocks/minerals are defined as high-density rocks/minerals.

2. Now weigh the rock samples one by one in a dry state: place them in the small string bag and hang the bag on the hook of the spring balance. When the spring stops moving, take as precise a reading as possible (N = Newton) and note this on the form. Most of the samples will weigh less than 200g, which is why the 2 N-spring balance can be used; but as the basalt samples weigh more, you will have to use the 5 N-spring balance to weigh them.

3. Pour 500 ml of water into the beaker.

4. Now, re-weigh the samples but this time weigh them when they are fully submerged in water. Make sure that the sample does not touch the bottom or sides of the beaker and that that the long hook of the spring balance does not touch the water.

5. Calculate the density of the various rocks (a spreads-heet is useful for this procedure).

Download the excel spreadsheet with the calculator on www.questforoil.com/qfo-for-schools

Archimedes was a Greek mathematician, physicist and engineer who lived most of his life (c. 287-212 BC) in Syracuse on Sicily. He left abundant writings with theoretical considera-tions and mathematical calculations of physical conditions. They were not seriously re-examined in Europe (translated from Arabic sources - and subsequently directly from Greek) until the Renaissance where they exerted a strong influ-ence on the development of the natural sciences.

But Archimedes was also a practician and several of his inventions are still in use to this day, such as the block-and-tackle pulley system and Archimedes screw (a "never-ending screw" used for raising water), but only a few isolated details about them have survived. Legend has it that when he discovered the principle of the weight of a fluid displaced by a body, he stood up while taking a bath and shouted "Eureka!". Today this concept is used when a complex correlation is understood and, for instance, the EUs industrial programme EUREKA has taken its name from this expression.

Source: Den store danske Encyklopdi (Danish encyclopaedia).

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DiscussionWhat does a rocks density tell you about: Its composition of minerals? Its formation process?

Conclusion

Results

Rock Weight in air, g

=1000 x N/9.82

Weight in water, g

=1000 x N/9.82

Weight loss, g =

volume,

cm3

Density, g/cm3

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3.6 The content of water and organic material in soil

TheorySoil contains minerals, water and air, as well as large or small amounts of organic substances, such as plant residue, animals and micro-organisms. By subjecting a soil sample to high heat, it is possible to burn off the organic components leaving only the minerals.

PurposeTo determine the percentage of organic substances con- tained in a soil samples dry matter.

Materials Soil sampleCrucibleBunsen burnerTongs for holding the crucibleWeighing scalesRacks

ProcedureDetermine the moisture content:1. Weigh out 20 g of soil and place the sample in an oven at 110o C for 24 hours2. Weigh the sample and calculate the water loss

Determine the content of organic material1. Weigh a dried soil sample do not use more than about 20 g2. Place the soil sample in a small porcelain crucible and

heat it over a Bunsen burner until it is red hot.

IMPORTANT:Carry out the experiment in a fume cupboard if possible! The sample should be red-hot for at least 25 minutes.

3. Weigh the soil sample again

Calculating the results4. Calculate the soils content of organic material (%) by

dividing its weight after heating by its weight before heating and multiplying this by 100.

Example of experiment set-up

Answer sheetQuest for Oil

Task:

Task: