Petroleum Engineering Assignment 1Due Date: 15th of April 2013 Lateef Akanji (Ph.D., D.I.C.) Petroleum and Gas Engineering University of Salford
[email protected] October 14, 2012 UoS Well Test Equations ∆Pskin = (Pwf )measured − (Pwf )calculated ∆Pskin s = qµB 2πκh Jmeasured P − Pwf + ∆Pskin = Jcalculated P − Pwf 70.6µB −948φµctr2 ∆P = − q1Ei kh κt ∆G = VuLco∆P ρo + (q2 − q1)Ei −948φµctr2 κ(t − t1) C = VuLco Np tp = q ∆P m = Cycle κtp tpDA = φµctA PDM BH = 2.3026(P ∗ −P )/m qµB κ = 0.183 mh qµB κ = 162.6 mh (P1hr − Pwf ) κ s = 1.1513 − log + 3.2255 2 m φµctrw (Pi − Pwf (t1)) κ s = −1.1513 + logt1 + log + 0.35173 2 m φµctrw
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[email protected] h∆P κ = 141.64e κ tM φct = tD µr2 2 rD M l.2 tL ∆tc tL ∆tc 2 2 F ig qµB (PD )M h ∆P M −4 2.uk Page 2 of 25 .UoS Well Test Equations qµB ∆PD κ= 2πh∆P κ= tL ∆tc tL ∆tc 2 F ig 2 qµB (PD )M 2πh ∆PM κ tM φct = 2 µr tD 2 rD M or in field unit qµB ∆PD κ = 141.t.ac. uk Page 3 of 25 .ac. B.t. Determine the relative ages in Figure 1 2. Describe the sequence of events that resulted in the formation of the geological features observed in Figure 1
[email protected] Petroleum Geology :Geologic Features Figure 1: Geologic feature Question 1 1. C and D 3. Name the features marked A. Identify the rock types in the area shown Figure 2 2.UoS Petroleum Geology :Geological Map Interpretation Question 1 Figure 2: Geological map Question 2 1.t. Determine the relative ages of the rocks 3.uk Page 4 of 25 . Name the geological structures that you are able to identify (in the case of folds. draw their axes) 4. Describe the geological history of the area
[email protected]. UoS Exploration : Exploration techniques Question 2 Question 3 1. State and define the principle methods of exploration and reservoir prediction 2.t. What sources of energy are most often used in seismic exploration?
[email protected]. What are the principal uses of seismic data l. What are the two methods commonly used in seismic prospecting? (a) Which is most often used? (b) Which gives the most information? 3. Describe hydrocarbon indicators on a seismic section 4.uk Page 5 of 25 . akanji@salford. describe the major subdivisions and brief geological history of the North Sea 2. Discuss the historical oil and gas production profile from the UK North Sea and the future direction l.UoS Petroleum Geology (Case-studies GP1 ):UK North Sea Question 3 Question 4 1.t.uk Page 6 of 25 . Using a simplified map. Describe the diffferent kinds of sedimentary rock and fluid types found in the North Sea and relate them to the depositional processes that led to their formation 5.ac. Describe the major distributions of oil and gas fields in the Southern North Sea (SNS) basin and adjacent onshore UK areas 3. Using a simplified stratigraphic column describe the oil and gas fields found in the Northern North Sea (NNS) 4. Discuss the historical oil and gas production profile from the Niger Delta and the potentials for future exploitation l. Using a simplified map. Describe the diffferent kinds of sedimentary rock and fluid types found in the Niger Delta and relate them to the depositional processes that led to their formation 5.UoS Petroleum Geology (Case-studies GP2 ):Nigerian Niger Delta Question 4 Question 5 1. describe the major subdivisions and brief geological history of the Nigerian Niger Delta basin 2.uk Page 7 of 25 .ac. Using a simplified stratigraphic column describe the oil and gas fields found in the Nigerian Niger Delta basin 4.t. Describe the major distributions of oil and gas fields in the Niger Delta basin 3.akanji@salford. t. Discuss the historical oil and gas production profile from the Arabian Gulf and the potentials for future exploitation l.UoS Petroleum Geology (Case-studies GP3 ):Arabian Gulf Question 5 Question 6 1. Using a simplified stratigraphic column describe the oil and gas fields found in the Arabian Gulf basin 4.ac.uk Page 8 of 25 . Describe the major distributions of oil and gas fields the Arabian Gulf basin 3. describe the major subdivisions and brief geological history of the Arabian Gulf basin 2. Describe the diffferent kinds of sedimentary rock and fluid types found in the Arabian Gulf and relate them to the depositional processes that led to their formation 5.akanji@salford. Using a simplified map. Using a simplified map.UoS Petroleum Geology (Case-studies GP4 ):Gulf of Mexico Basin Question 6 Question 7 1.ac. Describe the diffferent kinds of sedimentary rock and fluid types found in the Gulf of Mexico and relate them to the depositional processes that led to their formation 5. Describe the major distributions of oil and gas fields in the Gulf of Mexico 3.akanji@salford. Using a simplified stratigraphic column describe the oil and gas fields found in the Gulf of Mexico 4. Discuss the historical oil and gas production profile from the Gulf of Mexico and the potentials for future exploitation l. describe the major subdivisions and brief geological history of the Gulf of Mexico basin 2.t.uk Page 9 of 25 . ] 457.48 meters [2o per 100f t. 333. Using Figure 3 and the information provided in Table 2. Determine the relative position of the rig and target (a) rectangular coordinates (b) polar coordinates Table 1: Coordinates of rig and target T arget N S (meters) EW (meters) 964 −144 Rig 1334 653 2.UoS Drilling (Ass ): Drilling Engineering Question 7 Question 8 1. 500 f t.2 meters [1.akanji@salford. design a build and hold trajectory Table 2: Build and hold trajectory design Vertical depth Horizontal displacement Kick-off depth Build rate 3. 560 f t.uk Page 10 of 25 .ac.] 2o per 30. The target and the rig coordinates of a well are given in Table 1. determine the following: (a) radius of curvature of the build section (b) hold angle (c) measured depth (M D) at start of Hold section (M Dhold) (d) measured depth (M D) at total depth (M DT D ) l.688 meters [10.] 3.] 1.5 meters [4. 375 f t. 218.t. From your design. ac.uk Page 11 of 25
[email protected] Drilling (Ass ): Drilling Engineering Question 8 Figure 3: A build and hold trajectory l. Explain the following production related terms.akanji@salford. Describe the following well-test methods and state the main objectives of conducting each (a) Injectivity test (b) Fall-off test (c) Interference test (d) Drill-stem test (e) Pulse test l.uk Page 12 of 25 .UoS Production & Well-Test :Well-Test Objectives Question 8 Question 9 1.t.ac. stating all related equations (a) Productivity index (b) Vertical lift performance (c) Inflow performance relationship (d) Gas reservoir deliverability 2. m (b) the pressure at t = 10 hrs (c) the permeability. κ (d) the skin effect.2 × 10−9 P a−1[8.9f t.1m [0.2 cp] h = 21 m[68.2 × 10−3 P a − s[9.26 ct = 1.2 bbl/d] 1.32 µo = 9. Plot Pwf versus time on a semilog coordinate sheet (Sheet A) 2.uk Page 13 of 25
[email protected] Production & Well-Test : Pressure Drawdown Question 9 Question 10 Table 3 is a pressure drawdown test data from a well in an undersaturated reservoir with the following properties: Pi = 20.2 m3/d[108.17 Swi = 0. determine: (a) the gradient.7 M P a[3002.] φ = 0.] q = −17.27 × 10−61/psi] rw = 0. From your plot and using appropriate equations.328 f t.ac. s (e) whether the system is damaged or stimulated l.3 psi] Boi = 1. 35 18.ac.uk Page 14 of 25 .41 18.t.29 18.38
[email protected] 18.25 Figure 4: Sheet A l.UoS Production & Well-Test : Pressure Drawdown Question 10 Table 3: Pressure drawdown test data T ime(hours) 32 43 53 64 72 81 110 Pwf (M P a) 18.32 18. l. Question 11 continued on next page. Figure 5 is a pressure build-up curve from a reservoir with a limited drainage area.8 acre). (a) Determine the production time tp (b) Estimate the slope. . Use Figure 6 and the following additional data.ac.t. estimate the Pws(1hour) and the corresponding Pwf (d) Why is the Pws(1hour) different from the corresponding Pwf ? Figure 5: Pressure build-up curve with a limited drainage area 2.uk Page 15 of 25 . m (c) From the graph. Using the Matthews-Brons-Hazenbroek (MBH)
[email protected] × 106 m2 (103.UoS Production & Well-Test : Build-up & reservoir pressure Question 10 Question 11 1. determine the mean pressure of the drainage area of a well in the above reservoir which is placed at the center of a square with a surface A = 0. . ac.1 m [0.2 × 10−9P a−1 [8. cumulative production q = 38.52 (rb/stb) Pi = 20.3 m3/d [241bbl/d].t.328 f t] Question 11 continued on next page. .3 psi] µo = 9.17 [ ] Swi = 0. l.7 M P a [3002. production rate before shut-in Boi = 1.uk Page 16 of 25 .9 ft] φ = 0.25 [ ] ct =
[email protected] × 10−61/psi] rw = 0.2 × 10−3 Pa-s [9.UoS Production & Well-Test : Build-up & reservoir pressure Question 11 (continued) Figure 6: MBH dimensionless pressure for different well locations in a square drainage area (after MatthewsBrons-Hazenbroek) Additional pressure build-up data Np = 21409 m3 [134648bbl]. .2 cp] h = 21 m [68. 4 m [368.8 Additional data q = 300 m3/d [= 1887bbl/d] µ = 0. The distance to the observation well is 112.82 × 10−3 Pa-s [0. The measured pressure changes are drawn on a transparent sheet versus t (hour). During an interference test. and matched by parallel shifting in Figure 7 with the type curve.0 h = 12 m [39.uk Page 17 of 25 . water was injected in the active well for 22
[email protected] t] (a) Determine the permeability.4f t] r = 112. In the match point: (a) tM = 100hours 2 (b) (tD /rD )M = 50 (c) ∆PM = 105 Pa [= 14. κ and (b) φct l.8f t].UoS Production & Well-Test : Interference and Diagnostics Question 11 (continued) Question 12 1.ac.5psi] (d) PD M = 0.82cp] Bw = 1.4 m [368.
[email protected] Production & Well-Test : Interference and Diagnostics Question 12 Figure 7: Illustration of type curve matching for an interference test l.uk Page 18 of 25 .ac. uk Page 19 of 25 .t. Figure 8: Well test interpretation models l. The corresponding pressure change and derivative plots are also shown on a log-log plot.UoS Production & Well-Test : Interference and Diagnostics Question 12 Question 13 Figure 8 is a well test interpretation models for wells near a single fault. channel system and wedge systems. Analyze each of the plots.ac.akanji@salford. If the density of the oil is 900 kg/m3. 1. .uk Page 20 of 25 . the water saturation is 0. and the oil saturation is 0.akanji@salford. describe the following 1. how much oil (in kg) is contained in the reservoir? Question 15 With the aid of annotated phase envelope diagrams. Ignoring the expansion of the oil that would occur when it is produced from the reservoir. dry-gas and wet gas 3. the total volume (at standard conditions) of gas initially in place (GIIP) Question 16 continued on next page. Determine: 1. 10 m thick.t. light. intermediate and heavy crude systems Question 16 Given the gas production data shown in Table 4. and with a 5 km radius in the horizontal plane. how many barrels of oil are in this reservoir? (One barrel = 0.1589 m3). l. 2. The mean porosity of the reservoir is 15%. retrograde condensation.7. .3.UoS Reservoir Performance : Reservoir Engineering Question 13 Question 14 Consider a reservoir that is shaped like a circular disk. cricondenbar and cricondentherm 2.ac. 09 11.t. the volume of gas (Gp) that will be produced at the abandonment pressure of 3 M P a when Z = 0.1 23.1 2.89 Gp (108 m3 ) 0 6.88
[email protected] 0.uk Page 21 of 25 .UoS Reservoir Performance : Reservoir Engineering Question 16 (continued) Table 4: Data from a gas reservoir P ressure(M P a) 25 24 23 22 21 Z 0. Explain why the abandonment pressure is not 0.86 0.1 M P a (1 atm) l.95 3.ac.87 0.8 17. if fluid is flowing parallel to the layering? 2. in m3/s? 2.uk Page 22 of 25 . in equal volumetric proportions. where k1 = 1000 mD. but occurring in a ’random’ spatial distribution.ac. k2 = 100 mD. a pressure drop of 100 kP a is imposed along a core that has length of 10 cm. What will be the volumetric flowrate Q of the water. if fluid is flowing perpendicular to the layering? 3. 1 m thick.akanji@salford. Estimate the effective permeability in this case. l.UoS Reservoir Rock : Rock properties Question 16 Question 17 In a laboratory experiment. 1. The permeability of the core is 200 mD. and the viscosity of water is 0. and a radius of 2 cm. rock 2 and rock 3. in m/s? Question 18 Consider a layered reservoir consisting of alternating layers. What is the effective permeability of this rock. and k3 = 10 mD. of rock 1.t.001 P a − s. Imagine that the reservoir consists of these three rock types. 1. What is the numerical value of q = Q/A. its porosity is 15%. What is the effective permeability of this rock. 05 mm 1. If the radius of the blob is
[email protected] Page 23 of 25 . The surface tension between the oil and water is 0.ac.UoS Reservoir Rock : Rock properties Question 18 Question 19 Consider a small blob of oil surrounded by water.02 N m.t. What is the value of the capillary pressure? 2. Is the pressure higher in the oil or the water? l. 059 0. the apparent molecular weight (AMW) 2.ac.035 0.UoS Reservoir Fluid : Fluid properties Question 19 Question 20 Table 5 is the fluid compositional data of a gas reservoir.31 1.000 Question 21 An oil reservoir has the compositional data given in Table 6 1.046 0.t. mole fraction 0. the composition in volume fraction Table 5: Data from a gas reservoir Component Methane Ethane Propane Isobutane n-butane Composition.00 l.030 1. What is the API gravity of the oil? Use ideal-solution principles Table 6: Data from a gas reservoir Component n-butane n-pentane n-hexane Mole fraction 0.uk Page 24 of 25 . the specific gravity γ 3.akanji@salford. Compute 1.29 0.40 0.820 0. the composition in weight fraction 4. akanji@salford. 365 1.t. Draw a pattern of the brine Table 7: Data from a gas reservoir Component Na Ca Mg S 04 Cl C 03 HC 03 Mole fraction 7. The analysis of a formation water is given in Table 7. 582 305 521 14.uk Page 25 of 25 .UoS Reservoir Fluid : Fluid properties Question 21 Question 22 1.ac. 162 705 0 l. Convert the concentrations of solids for the brine to (a) milligrams per liter (b) percent solids (c) milliequivalents per liter 2.