Rondon 1N PVT Report

Reservoir Fluid Study

for

Occidental de Colombia

Rondon 1N Well

RFL05097

Core Laboratories Venezuela, S.A.

Calle 25 (Carretera Via El Mojan) Km 3 al lado dwe la Coca-ColaTel +58 261 7574611, fax +58 261 7578684

The analyses, opinions or interpretations in this report are based onobservations and material supplied by the client to whom, and for whoseexclusive and confidential use, this report is made. The interpretations oropinions expressed represent the best judgement of Core LaboratoriesVenezuela, S.A. (all errors and omissions excepted); but Core LaboratoriesVenezuela, S.A. and its officers and employees assume no responsibility and make no warranty or representations as to the productivity, proper operationor profitability of any oil, gas or any other mineral well formation inconnection with which such report is used or relied upon.

Core Laboratories Venezuela, S.A.Km 3 Via El Mojan. Parcelamiento Buena VistaMaracaibo, Edo. Zulia-VenezuelaTel: 58 261 7574611Fax: 58 261 7578684Web: http://www.corelab.com

Sincerely,Core Laboratories Venezuela, S.A

Gustavo CabezaProject ManagerReservoir Fluids Laboratory

August 1st of 2005

Occidental de Colombia.Bogota, Colombia.

Attention : Eng. Ciro Pinto Rizzo Subject: Reservoir Fluid Study Well: Rondon 1NFile: RFL 05097

Gentlemen:

On May 20th of 2005, two wellhead samples were collected by Core Laboratoriesrepresentativesfrom the subject well and were delivered to our fluid laboratory in Maracaibo,Venezuela for performance of a reservoir fluid study.

Upon arrival at the laboratory, the samples were validated by measuring their bubble pointpressures at laboratory temperature; the selected sample was restored to reservoirconditions for subsequent PVT testing. Additional tests were required during the course ofthe study, preliminary results were provided to the client during the course of the laboratorystudy, as well. Final report is presented in the following pages.

It has been a pleasure to perform this study for Occidental de Colombia. Should anyquestions arise or if we may be of further service in any way, please do not hesitate tocontact us.

Occidental de ColombiaRondon 1N Well___________________________________________________________________________________________RFL05097

Table of Contents

Section A - Summary of PVT Methods and Data Page

Summary of PVT methods....................................................................................................... A.1-A.2Summary of PVT data.............................................................................................................. A.3

Section B - Summary of Samples Received and Validation Data

Well information........................................................................................................................ B.1Summary of samples received and validation data.................................................................. B.2

Section C - Compositional Analysis of Bottomhole Reservoir Fluid

Compositional Analysis of Reservoir Fluid to C36+.................................................................. C.1-C.2

Section D - Constant Composition Expansion

Single phase fluid properties at reservoir temperature............................................................. D.1Constant composition expansion at reservoir temperature...................................................... D.2Graphs of constant composition expansion at reservoir temperature...................................... D.3Constant composition expansion at different temperatures..................................................... D.4

Section E - Differential Vaporization

Differential vaporization data.................................................................................................... E.1Graphs of differential vaporization............................................................................................ E.2Differential vaporization data adjusted to surface conditions.................................................... E.3

Section F - Viscosity of Reservoir Fluid

Reservoir fluid viscosity data at Reservoir Temperature.......................................................... F.1-F.2

Section G - Separation Test of Reservoir Fluid

Atmospheric Flash test at 75 °F................................................................................................ G.1Molecular composition of evolved gas during atmospheric flash at 75 °F................................. G.2

Atmospheric Flash test at 140 °F.............................................................................................. G.3Molecular composition of evolved gas during atmospheric flash at 140 °F............................... G.4




___________________________________________________________________________________________Core Laboratories Venezuela, S.A.


Table of Contents, continued

Section H - Appendix

Data used in gas compositional calculations............................................................................ H.1Data used in liquid compositional calculations......................................................................... H.2Crude oil caracterization.......................................................................................................... H.3Crude oil distillation.................................................................................................................. H.4



Section A - Summary of Analysis Methods and PVT Data



Summary of Analysis Methods

Sample ValidationThe bubble point pressure at ambient temperature and free water content of each wellheadsample were determined as initial quality checks. From this quality control, the samples showedgood agreement with respect to the measured bubble point pressures and did not contain freewater. Therefore, the samples were deemed valid and were used to continue with testing

Heat TreatmentEach wellhead sample was heated to 200°F prior to subsampling for every PVT test to avoidwax or asphaltene deposition problems

Pressurized Wellhead Fluid CompositionApproximately 30 cc of pressurized fluid was flashed to atmospheric pressure at 120 °F andseparated into its respective gas and oil phases. The evolved gas and residual liquid wereanalyzed separately, using gas-liquid chromatography and recombined on a weight basis toproduce a C36+ weight percent composition. Calculations to mole% and the plus fractionsproperties are described below.

Gas CompositionsGas compositions were measured using a "one shot" Varian 3800 gas analyzer using methodGPA 2286. The gas chromatograph utilizes 3 columns to clearly identify all the elutedcomponents from N2, CO2 and C1 through C11+. The chromatograph is calibrated twice perweek using air and synthetic hydrocarbon gas with known compositions. The resultantcalibration data is checked statistically against previous calibrations prior to performing analyseson unknown samples.

Liquid CompositionResidual/stocktankliquid composition were measured using a Varian 3400 chromatograph. Thegas chromatograph utilizes a cold on-column, "sandwich injection" technique to ensure that arepresentative sample is injected and swept onto the column. The sample is run twice; first theoriginal fluid and then the same spiked with n-tetradecane. This allows the laboratory to take intoaccount any heavy end (C36+) losses that may have occurred, during the chromatographic runand make an accurate correction prior to reporting the liquid composition. The data obtainedfrom the gas chromatograph is in weight percent. Calculations to mole% and the plus fractionsproperties are described below.

The chromatograph is checked twice per week as well, using a gravimetric n-paraffin mixcontaining a range of pure components from C8 through C36 and a synthetic gas-oil mix(D2887) with known composition. The resultant calibration data is checked statistically againstprevious calibrations prior to performing analyses on unknown samples.

A.1___________________________________________________________________________________________Core Laboratories Venezuela, S.A.


Summary of Analysis Methods (Continuation)

Calculation of Mole% Compositions and Plus Fraction PropertiesThe residue or stocktank liquid whole sample molecular weight and density are measured usinga cryscope unit and a PAAR densimeter respectively.

The mole% data is calculated using GPSA mole weight and density data, where individualcomponents are identified, from carbon dioxide through decanes. Katz and Firoozabadi data areused from undecanes through pentatriacontanes. The residue mole weight and density valuesare calculated so that the pseudo average mole weight and density are the same as themeasured values. This can lead to anomalous residue mole weights and densities where theKatz and Firoozabadi values may not be suitable for the isomer groups detected.

Other alternativesare to use an assumed C36+ molecular weight and density value, use a linearextrapolation technique for components from C10 to C35 to calculate the C36+ properties or toutilise distillation analysis to produce a C11+, C20+ or C36+ residual oil fraction and physicallymeasure the molecular weight and density.

Constant Composition ExpansionA portion of the wellhead fluid sample was charged to a high pressure visual cell and thermallyexpanded to the reservoir temperature of 225 °F. A constant composition expansion wascarried out during which the bubble point pressure and pressure-volume data for the singlephase and two phase fluid were determined. The density of the single phase fluid was alsodetermined by weighing measured volumes pumped from the cell at 5000 psig. Density data forother pressures were calculated using the volumetric data.

Differential VaporizationThis was carried out in a high pressure visual cell at reservoir temperature. At several pressurestages below the observed saturation pressure, the sample was stabilized. The gas evolvedwas then pumped out of the cell and its volume, compressibility and composition weredetermined. The final stage was carried out at atmospheric pressure when the residual liquidwas pumped out of the cell and its density was determined



Summary of Analysis Methods (Continuation)

ViscosityLive-oil viscosity was measured in a rolling ball viscometer at reservoir temperature. Viscositydeterminations were carried out over a wide range of pressures from above the reservoirpressure to atmospheric pressure.

The measurements were repeated at each pressure stage until five or more results agreed towithin 0.5% of the ball roll-time. The densities, obtained from the constant compositionexpansion and differential vaporization tests, were used in the calculation of viscosities incentipoise.

Separator TestsFive atmospheric flash tests at different temperatures each were carried out using a pressurizedtest separator cell. A portion of the wellhead sample, at a pressure above saturation pressure,was pumped into the separator cell and stabilized at ambient pressure and test temperature. Thgas evolved was pumped out of the cell and the volume and composition were determined. Thefinal stage was carried out at atmospheric pressure and ambient temperature and the density ofthe residual liquid was determined.

Crude Oil CaracterizationA set of atmospheric tests was also performed accordingly with ASTM methodologies and theirresults are presented in the Appendex.



Summary of PVT Data

Constant Composition Expansion at 225 °F

Saturation pressure (bubble-point) 508 psig

Average single phase compressibility 7.62 X 10-6 psi (from 3750 psig to 508 psig)

Thermal expansion at 5000 psig 1.0761 vol at 225 °F / vol at 60°F

Differential Vaporization at 225 °F

Solution gas-oil ratio at saturation pressure 109 scf/bbl of residual oil at 60°F

Relative oil volume at saturation pressure 1.148 vol/vol of residual oil at 60°F

Density at saturation pressure 0.7759 g cm-3

Wellhead Fluid Viscosity at 225 °F

Viscosity at reservoir pressure 1.622 centipoise at 3750 psig

Viscosity at saturation pressure 1.166 centipoise at 508 psig

Separator Test DataPressure Temperature Formation Volume Total Solution Stocktank Oil

(psig) (°F) Factor Gas-oil ratio Density at 60 °F(scf/bbl) (g cm-3)

Test 1

508 225 1.127 1030 75 0.8505

Test 2

508 225 1.132 1080 140 0.8531

Test 3

508 225 1.140 1160 180 0.8547

Test 4

508 225 1.147 1210 200 0.8562

Test 5

508 225 1.155 1280 220 0.8572



Section B - Summary and Validation Data of Samples Received



Reported Well and Sampling Information

Reservoir and Well Information

Field........................................................................ RondonWell......................................................................... Rondon 1NReservoir Fluid........................................................ Black Oil Formation................................................................ *Current Reservoir Pressure .................................... 3750 psigReservoir Temperature........................................... 225 °F

Installation............................................................... *Sand....................................................................... M2 - APerforated Interval ................................................. 10154' - 10160´

Sampling Information

Date sampled.......................................................... 20-May-05Time sampled ........................................................ 05:30Type of samples..................................................... Wellhead Sampling company.................................................. Core Laboratories Colombia

Choke..................................................................... *Status of well.......................................................... *

Bottomhole pressure............................................... 3750Bottomhole temperature......................................... n/a

Wellhead pressure.................................................. 305 psigWellhead temperature............................................ 100 °F

Separator pressure ................................................ *Separator temperature ........................................... *

Pressure base......................................................... 14.7 psiaTemperature base ................................................. 60°F

Separator gas rate.................................................. *Separator oil rate ................................................... *Water flowrate......................................................... n/aGas gravity (Air = 1)................................................ *Supercompressibility factor..................................... *H2S......................................................................... *CO2........................................................................ *BS&W...................................................................... *Oil gravity ................................................................ *

Comments: * Data not provided

___________________________________________________________________________________________Core Laboratories Venezuela, S.A. B.1


Summary of Samples Received

Wellhead SamplesLaboratory

Sample Cylinder Sampling :- Bubble point :- Water SampleNumber Number Pressure Temp. Pressure Temp. Cut Volume

(psig) (°F) (psig) (°F) (%) (cm3)

1.1 436251D 305 100 310 76 0.2 890

1.2 897612C 305 100 305 76 0.2 890

Note:

Sample No.1.1 and 1.2 were selected for compositional and further PVT analysesOne 1000 cc plastic container with crude oil sample was also received to perform crude oil caracterization

___________________________________________________________________________________________Core Laboratories Venezuela, S.A. B.2


Section C - Compositional Analysis of Wellhead Fluid



Compositional Analysis of Wellhead Sample to C36 plus

Component Mole % Weight %H2 Hydrogen 0.00 0.00H2S Hydrogen Sulphide 0.00 0.00CO2 Carbon Dioxide 0.66 0.13N2 Nitrogen 0.20 0.03C1 Methane 10.83 0.79C2 Ethane 2.37 0.33C3 Propane 2.35 0.47iC4 i-Butane 0.98 0.26nC4 n-Butane 1.67 0.44iC5 i-Pentane 1.12 0.37nC5 n-Pentane 1.08 0.36C6 Hexanes 2.01 0.79C7 Heptanes 4.11 1.74C8 Octanes 6.15 3.01C9 Nonanes 5.28 2.89C10 Decanes 4.76 3.04C11 Undecanes 4.34 2.92C12 Dodecanes 4.00 2.95C13 Tridecanes 4.03 3.23C14 Tetradecanes 3.88 3.37C15 Pentadecanes 3.35 3.16C16 Hexadecanes 2.76 2.80C17 Heptdecanes 3.02 3.28C18 Octadecanes 2.18 2.50C19 Nonadecanes 1.85 2.23C20 Eicosanes 1.72 2.16C21 Heneicosanes 1.59 2.11C22 Docosanes 1.48 2.06C23 Tricosanes 1.40 2.04C24 Tetracosanes 1.36 2.06C25 Pentacosanes 1.36 2.14C26 Hexacosanes 1.25 2.05C27 Heptacosanes 1.23 2.11C28 Octacosanes 1.18 2.09C29 Nonacosanes 1.15 2.12C30 Triacontanes 1.07 2.03C31 Hentriacontanes 0.97 1.91C32 Dotriacontanes 0.79 1.61C33 Tritriacontanes 0.73 1.54C34 Tetratriacontanes 0.87 1.88C35 Pentatriacontanes 0.64 1.42C36+ Hexatriacontanes plus 8.23 27.58

_____ _____Totals : 100.00 100.00

Note: 0.00 means less than 0.005.

___________________________________________________________________________________________Core Laboratories Venezuela, S.A. C.1


Compositional Analysis of Wellhead Sample to C36 plus

Calculated Residue Properties

C7 plus Mole% 76.73Molecular Weight (g mol-1) 274Density at 60°F (g cm-3) 0.8690



C36 plus Mole % 8.23Molecular Weight (g mol-1) 734Density at 60°F (g cm-3) 0.9503

Calculated Whole Sample Properties

Average mole weight (g mol-1) 219Density at 60°F (g cm-3) 0.8419

___________________________________________________________________________________________Core Laboratories Venezuela, S.A. C.2


Section D - Constant Composition Expansion (CCE)



Constant Composition Expansion at 225°F

Single-phase Fluid Properties

Saturation pressure (bubble-point pressure) 508 psig

Thermal expansion factor of single phase fluid at 5000 psig(Vol at 225°F)/(Vol at 60°F) 1.0761 vol / vol

Average single phase compressibility(From 3750 psig to 508 psig) 7.62 x 10 -6 psi-1

Density at saturation pressure 0.7759 g cm-3

Mean Single-phase Compressibilities

Pressure Range MeanInitial Pressure Final Pressure Compressibility

(psig) (psig) (psi-1) (1)

5000 3750 6.45 x 10 -6

3750 2500 6.81 x 10 -6

2500 1500 7.40 x 10 -6

1500 508 8.85 x 10 -6

(1) Mean compressibility = (V2-V1) / [(V1+V2)/2] x 1/(P1 - P2)

___________________________________________________________________________________________Core Laboratories Venezuela, S.A. D.1


Constant Composition Expansion at 225°F

Pressure Relative Density Instantaneous Y-function (3)(psig) Volume (1) (g cm-3) Compressibility

(psi-1 x 10-6) (2)

5000 0.9678 0.80174500 0.9709 0.7992 6.374000 0.9740 0.7966 6.483750 Reservoir pressure 0.9756 0.7953 6.573500 0.9772 0.7940 6.643000 0.9805 0.7913 6.772500 0.9839 0.7886 6.972000 0.9875 0.7857 7.231500 0.9913 0.7827 7.611000 0.9953 0.7795 8.22900 0.9962 0.7789 8.79800 0.9971 0.7782 9.07700 0.9980 0.7774 9.43600 0.9990 0.7767 9.90508 Saturation pressure 1.0000 0.7759 10.51506 1.0015504 1.0029502 1.0044500 1.0060480 1.0221464 1.0364421 1.0823 2.425361 1.1713 2.284302 1.3032 2.145249 1.4860 2.021207 1.7063 1.922166 2.0365 1.826132 2.4678 1.746116 2.7554 1.709101 3.1022 1.67373 4.0853 1.608

(1) Relative Volume = V / Vsat ie. volume at indicated pressure per volume at saturation pressure. (2) Instantaneous compressibility = (V2-V1) / V1 x 1/(P1-P2)(3) Y-function = (Psat - P ) / ((Pabs)(V/Vsat - 1)).



Graphs of Constant Composition Expansion at 225 ºF

Relative Volume vs Pressure

Y Function vs Pressure

0.9650

0.9700

0.9750

0.9800

0.9850

0.9900

0.9950

1.0000

0 1000 2000 3000 4000 5000

Pressure, psig

Rel

ativ

e vo

lum

e, V

/Vsa

t

0.000

0.500

1.000

1.500

2.000

2.500

3.000

3.500

4.000

0 100 200 300 400 500

Pressure, psig

Y Fu

nctio

n



Constant Composition Expansions at Different Temperatures

SaturationTemperature Pressures

(°F) (psig)

75 341140 402180 446200 471220 500225 508

Saturation Pressure vs Temperature

300

350

400

450

500

550

50 100 150 200 250

Temperature, °F

Satu

ratio

n Pr

essu

res,

psi

g



Section E - Differential Vaporization (DV)



Differential Vaporisation at 225°F

Solution Relative Relative Deviation Gas IncrementalPressure Gas-Oil Oil Total Density Factor Formation Gas Gravity

(psig) Ratio Volume Volume (g cm-3) (Z) Volume (Air = 1.000)Rs(1) Bod(2) Btd(3) Factor (4)

508 109 1.148 1.148 0.7759 Saturation Pressure400 91 1.141 1.286 0.7774 0.954 0.04456 0.875300 77 1.136 1.475 0.7787 0.957 0.05887 0.859200 59 1.129 1.906 0.7807 0.958 0.08644 0.875100 39 1.120 3.158 0.7828 0.967 0.16333 0.9660 0 1.084 0.7931 2.021

At 60°F = 1.000

Residual Oil Properties

Density of residual oil 0.8598 g cm-3 at 60°F

API 32.9

(1) GOR in cubic feet of gas at 14.70 psia and 60°F per barrel of residual oil at 60°F.(2) Volume of oil at indicated pressure and temperature per volume of residual oil at 60°F.(3) Volume of oil plus liberated gas at indicated pressure and temperature per volume of residual oil at 60°F.(4) Volume of gas at indicated pressure and temperature per volume at 14.70 psia and 60°F.

___________________________________________________________________________________________Core Laboratories Venezuela, S.A. E.1


Graphs of Differential Vaporisation

Solution Gas-Oil Ratio v Pressure

Relative Oil Volume v Pressure

0

20

40

60

80

100

120

0 100 200 300 400 500 600

Pressure (psig)

Gas

-Oil

Rat

io (s

cf /

bbl)

1.000

1.020

1.040

1.060

1.080

1.100

1.120

1.140

1.160

0 100 200 300 400 500 600

Pressure (psig)

Rel

ativ

e O

il Vo

lum

e (V

/Vr)



Differential Vaporisation Data Converted to Production Separator Conditions

Oil Solution Formation Gas FormationPressure Density Gas/Oil Volume Volume

(psig) (g cm-3) (scf / bbl) Factor FactorRs(1) Bo(1) Bg(2)

5000 0.8017 1.0964500 0.7992 1.0994000 0.7966 1.1033750 Reservoir pressure 0.7953 1.1043500 0.7940 1.1063000 0.7913 1.1102500 0.7886 1.1142000 0.7857 1.1181500 0.7827 1.1221000 0.7795 1.127900 0.7789 1.128800 0.7782 1.129700 0.7774 1.130600 0.7767 1.131508 Saturation pressure 0.7759 108 1.132400 0.7774 90 1.125 0.04456300 0.7787 76 1.120 0.05887200 0.7807 58 1.113 0.08644100 0.7828 39 1.105 0.163330 0.7931 0 1.059

Notes:

(1) Differential data corrected to surface separator conditions of :-

Stage 1 0 psig and 140°F

Rs = Rsfb - (Rsdb - Rsd) x (Bofb / Bodb)

Bo = Bod x (Bofb/Bodb)

(2) Volume of gas at indicated pressure and temperature per volume at 14.70 psia and 60°F.







Notes:












Notes:












Notes:








Section F - Reservoir Fluid Viscosity Data



Reservoir Fluid Viscosity Data at 225°F

Pressure Oil Calculated Oil/Gas(psig) Viscosity Gas Viscosity Viscosity

(cP) (cP) (1) Ratio

5000 1.7974500 1.7274000 1.6573750 Reservoir pressure 1.6223500 1.5873000 1.5172500 1.4462000 1.3761500 1.3061000 1.236900 1.221800 1.207700 1.193600 1.179508 Saturation pressure 1.166400 1.175 0.0132 89.1300 1.178 0.0131 90.0200 1.201 0.0129 93.2100 1.297 0.0124 104.70 1.753

(1) Calculated using the method of Lee, Gonzales and Eakin, JPT, Aug 1966.

___________________________________________________________________________________________Core Laboratories Venezuela, S.A. F.1


Graph of Reservoir Fluid Viscosity Data at 225°F

1.000

1.100

1.200

1.300

1.400

1.500

1.600

1.700

1.800

1.900

0 1000 2000 3000 4000 5000 6000

Pressure (psig)

Visc

osity

(cP)

___________________________________________________________________________________________Core Laboratories Venezuela, S.A. F.2


Section G - Separator Test Data



Separator Test Data - Test #1

Gas-Oil Gas-Oil Oil Formation Separation Gas GravityPressure Temperature Ratio Ratio Density Volume Volume of flashed gas

(psig) (°F) Rsfb (g cm-3) Factor Factor (Air = 1.000)(1) (2) Bofb (3) (4)

508 225 - 0.7759 1.127 Saturation Pressure

0 75 102 103 0.8445 1.007 1.105 *



API 34.7

Note

* Evolved gas collected and analysed to Undecanes plus

(1) GOR in cubic feet of gas at 14.70 psia and 60°F per barrel of oil at indicated pressure and temperature.(2) GOR in cubic feet of gas at 14.70 psia and 60°F per barrel of stocktank oil at 60°F.(3) Volume of saturated oil at 508 psig and 225°F per volume of stocktank oil at 60°F.(4) Volume of oil at indicated pressure and temperature per volume of stocktank oil at 60°F.

___________________________________________________________________________________________Core Laboratories Venezuela, S.A. G.1


Compositional Analysis of Separator Test Gas to C11+

Test StagePressure Stage, psig 0Temperature Stage, °F 75

Component Mole % Weight %

CO2 Carbon Dioxide 2.94 4.04N2 Nitrogen 0.98 0.86C1 Methane 53.21 26.67C2 Ethane 12.82 12.04C3 Propane 12.09 16.66iC4 i-Butane 3.57 6.48nC4 n-Butane 5.14 9.33iC5 i-Pentane 2.33 5.25nC5 n-Pentane 3.15 7.10C6 Hexanes 0.67 1.80 M-C-Pentane 0.43 1.13 Benzene 0.03 0.07 Cyclohexane 0.49 1.29C7 Heptanes 0.23 0.72 M-C-Hexane 0.64 1.96 Toluene 0.05 0.14C8 Octanes 1.03 3.68 E-Benzene 0.01 0.03 M/P-Xylene 0.04 0.13 O-Xylene 0.01 0.03C9 Nonanes 0.13 0.52C10 Decanes 0.01 0.04C11+ Undecanes Plus 0.00 0.00

Totals : 100.00 100.00Note: 0.00 means less than 0.005.

Calculated Residue Properties Mole Weight Density(g mol-1) (g cm-3 at 60°F )

C7+ Heptanes plus 103.3 0.7370C10+ Decanes plus 134.0 0.7780C11+ Undecanes plus _ _

Calculated Whole Gas PropertiesGas Gravity 1.105 (Air=1 @ 14.7 psia and 60°F)Whole Sample Mole Weight 32.01 g mol-1

Gross Calorific Value 1790 BTU/scf Net Calorific Value 1638 BTU/scf







0 140 104 108 0.8208 1.039 1.198 *



API 34.2

Note











C7+ Heptanes plus 102.2 0.7350C10+ Decanes plus 141.3 0.7840C11+ Undecanes plus 154.0 0.7950









0 180 109 116 0.8061 1.060 1.246 *



API 33.9

Note




















0 200 113 121 0.7995 1.071 1.312 *



API 33.6

Note




















0 220 118 128 0.7924 1.082 1.370 *



API 33.4

Note
















Section H - Appendix



Data Used in Gas Compositional Calculations

Component Mole Weight Density Component Mole Weight Density(g mol-1) (g cm-3 at 60°F) (g mol-1) (g cm-3 at 60°F)

Hydrogen * 2.016 N/A 33DMC5 * 100.20 0.6954Oxygen/(Argon) ** 31.999 1.1410 Cyclohexane * 84.16 0.7827Nitrogen (Corrected) ** 28.013 0.8086 2MC6/23DMC5 * 100.20 0.6917Methane ** 16.043 0.2997 11DMCYC5/3MC6 * 99.20 0.7253Carbon Dioxide ** 44.010 0.8172 t13DMCYC5 * 98.19 0.7528Ethane ** 30.070 0.3558 c13DMCYC5/3EC5 * 99.20 0.7262Hydrogen Sulphide ** 34.080 0.8006 t12DMCYC5 * 98.19 0.7554Propane ** 44.097 0.5065 Heptanes (nC7) * 100.20 0.6875i-Butane ** 58.123 0.5623 22DMC6 * 114.23 0.6994n-Butane ** 58.123 0.5834 MCYC6 * 98.19 0.7740Neo-Pentane * 72.15 0.5968 ECYC5 * 98.19 0.7704i-Pentane ** 72.150 0.6238 223TMC5/24&25DMC6 * 114.23 0.7060n-Pentane ** 72.150 0.6305 ctc124TMCYC5 * 112.21 0.751122DMC4 * 86.18 0.6529 ctc123TMCYC5 * 112.21 0.757423DMC4/CYC5 * 78.16 0.7129 Toluene * 92.14 0.87342MC5 * 86.18 0.6572 Octanes (nC8) * 114.23 0.70633MC5 * 86.18 0.6682 E-Benzene * 106.17 0.8735Hexanes (nC6) * 86.18 0.6631 M/P-Xylene * 106.17 0.867122DMC5 * 100.20 0.6814 O-Xylene * 106.17 0.8840M-C-Pentane * 84.16 0.7533 Nonanes (nC9) * 128.26 0.721224DMC5 * 100.20 0.6757 Decanes *** 134 0.778223TMC4 * 100.20 0.6947 Undecanes *** 147 0.789Benzene * 78.11 0.8820 Dodecanes *** 161 0.800

Data Source Refs :

* ASTM Data Series Publication DS 4B (1991) - Physical Constants of Hydrocarbon and Non-Hydrocarbon Compounds.

** GPA Table of Physical Constants of Paraffin Hydrocarbons and Other Components of Natural Gas, GPA 2145-96.

*** Journal of Petroleum Technology, Nov 1978, Pages 1649-1655. Predicting Phase Behaviour of Condensate/Crude Oil Systems Using Methane Interaction Coefficients - D.L. Katz & A. Firoozabadi.

Note :The gas mole % compositions were calculated from the measured weight % compositions using the most detailed analysis results, involving as many of the above components as were identified. The reported component mole % compositions were then sub-grouped into the generic carbon number components.

___________________________________________________________________________________________Core Laboratories Venezuela, S.A. H.1


Data Used in Liquid Compositional Calculations

Component Mole Weight Density Component Mole Weight Density(g mol-1) (g cm-3 at 60°F) (g mol-1) (g cm-3 at 60°F)

Hydrogen * 2.016 N/A Undecanes *** 147 0.789Hyd. sulphide ** 34.080 0.8006 Dodecanes *** 161 0.800Carbon Dioxide ** 44.010 0.8172 Tridecanes *** 175 0.811Nitrogen ** 28.013 0.8086 Tetradecanes *** 190 0.822Methane ** 16.043 0.2997 Pentadecanes *** 206 0.832Ethane ** 30.070 0.3558 Hexadecanes *** 222 0.839Propane ** 44.097 0.5065 Heptadecanes *** 237 0.847i-Butane ** 58.123 0.5623 Octadecanes *** 251 0.852n-Butane ** 58.123 0.5834 Nonadecanes *** 263 0.857i-Pentane ** 72.150 0.6238 Eicosanes *** 275 0.862n-Pentane ** 72.150 0.6305 Heneicosanes *** 291 0.867Hexanes ** 86.177 0.6634 Docosanes *** 305 0.872Me-cyclo-pentane * 84.16 0.7533 Tricosanes *** 318 0.877Benzene * 78.11 0.8820 Tetracosanes *** 331 0.881Cyclo-hexane * 84.16 0.7827 Pentacosanes *** 345 0.885Heptanes ** 100.204 0.6874 Hexacosanes *** 359 0.889Me-cyclo-hexane * 98.19 0.7740 Heptacosanes *** 374 0.893Toluene * 92.14 0.8734 Octacosanes *** 388 0.896Octanes ** 114.231 0.7061 Nonacosanes *** 402 0.899Ethyl-benzene * 106.17 0.8735 Triacontanes *** 416 0.902Meta/Para-xylene * 106.17 0.8671 Hentriacontanes *** 430 0.906Ortho-xylene * 106.17 0.8840 Dotriacontanes *** 444 0.909Nonanes ** 128.258 0.7212 Tritriacontanes *** 458 0.9121-2-4-T-M-benzene * 120.19 0.8797 Tetratriacontanes *** 472 0.914Decanes ** 142.285 0.7334 Pentatriacontanes *** 486 0.917

Data Source Refs :

* ASTM Data Series Publication DS 4B (1991) - Physical Constants of Hydrocarbon and Non-Hydrocarbon Compounds.

** GPA Table of Physical Constants of Paraffin Hydrocarbons and Other Components of Natural Gas GPA 2145-96.

*** Journal of Petroleum Technology, Nov 1978, Pages 1649-1655. Predicting Phase Behaviour of Condensate/Crude Oil Systems Using Methane Interaction Coefficients - D.L. Katz & A. Firoozabadi.

Note :The residue mole weight and density values ( eg heptanes plus, undecanes plus, eicosanes plus) are calculated so that the calculated average mole weights and densities correspond with the measured values. This can lead to anomalous residue mole weights and densities where the Katz and Firoozabadi values may not be suitable for the isomer groups detected.

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TEST DESCRIPTION FINAL RESULT LIMITES/*DILUTION UNITS OFMEASURE

TEST METHOD DATE TECHN

Agua 1.0 % v/v ASTM D 1796-97 06/23/05 YCHSedimento < 0.1 0.1 % v/v ASTM D 1796-97 06/23/05 YCHAgua y Sedimentos 1.0 0.1 % v/v ASTM D 1796-97 06/23/05 YCHGravedad API @ 60 oF 34.6 0.1 ASTM D 287-00 06/23/05 YCHAsfaltenos N-Heptano 0.60 0.05 % Peso IP 143-96 06/23/05 YCHParafinas 11.85 0.01 % Peso UOP 46-85 06/23/05 YCHPunto de Inflamacion (C. Abierta) 47 20 oF ASTM D 92-01 06/23/05 YCHContenido de Azufre 0.17 0.01 % Peso ASTM D 1552-01 06/27/05 MJContenido de Ceniza < 0.001 0.001 % Peso ASTM D 482-00 06/27/05 MJContenido de Sal < 1.0 1 Lbs./1000 bbls ASTM D 3230-99 06/27/05 MJPunto de Fluidez 4 -36 oC ASTM D 5853-00 06/23/05 YCHNiquel total (Ni) 5.0 0.5 mg/Kg SW-846/6010 B 06/28/05 AMVanadio total (V) 1.0 5 mg/Kg SW-846/6010 B 06/28/05 AMViscosidad Cinematica a 100 °F 5.35 0.1 cSt ASTM D 445-01 06/27/05 LOViscosidad Cinematica a 122 °F 4.34 0.1 cSt ASTM D 445-01 06/27/05 LOViscosidad Cinematica a 210 °F 2.28 0.1 cSt ASTM D 445-01 06/27/05 LOPresion de vapor Reid @ 100 °F 4.9 0.1 psi ASTM D 323-99 07/25/05 HRCalor de Combustion (Valor Calorífico) 19874 600 Btu/ lbs ASTM D 240-00 07/21/05 MJ

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CORE LABORATORIES L A B O R A T O R Y T E S T S R E S U L T S

JOB NUMBER: 250484 USTOMER: Occidental de Colombia ATTN: Uriel Sanchez

CLIENT I.D………………... Pozo: Rondon 1 N LABORATORY ID..... 250484-01DATE SAMPLED….........… 05/20/05 DATE RECEIVED..... 06/20/05TIME SAMPLED….............. TIME RECEIVED...... 13:00WORK DESCRIPTION........ REMARKS.................: Muestreado por: Cliente

TEST DESCRIPTION FINAL RESULT LIMITES/*DILUTION UNITS OFMEASURE

TEST METHOD DATE TECHN

Destilación atmosférica

Punto Inicial de Ebullicion 150 0 °F ASTM D 86-01 06/23/05 YCH

5% Destilado 228 0 °F

















90% Destilado NA 0 °F

95 % Destilado NA 0 °F

Punto Final Ebullicion 650 0 °F

Porcentaje Destilado 85.0 0Porcentaje Total Recuperado 99.5 0.1Porcentaje de Residuo 14.5 0.1Porcentaje de Perdidas 0.5 0.1

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Report prepared by Report approved by

Gustavo Cabeza David McEvoyProject Manager Laboratory ManagerReservoir Fluid Laboratory Reservoir Fluid Laboratory


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Rondon 1N PVT Report