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Exhibit 15.2



LOGO

THIRD PARTY REPORT

RESERVES ESTIMATION AND VALUATION OF

(CHAD AND KAZAKHSTAN  PKKR & KOLZHAN)

AS OF 31stDECEMBER, 2011

Prepared for

PETROCHINA COMPANY LIMITED

APRIL, 2012





CONFIDENTIAL

This document contains proprietary and confidential information which may not, without the express written

permission of Gaffney, Cline & Associates, be released to any third party in any form, copied in any way or

reproduced, nor utilized for any purpose except that for which it is intended, and must be returned upon request.

www.gaffney-cline.com







|           |  |            |  |               
|---------- |  | ---------- |  | --------------
|PetroChina |  | Copy No. 1 |  | KK1815 & K1816



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LOGO



|                            |  |          |   | 
|--------------------------- |  | -------- | - | 
|                            |  | Page No. |  
|INTRODUCTION                |  |          | 2 | 
|METHODOLOGY                 |  |          | 4 | 
|1 .    RESULTS SUMMARY      |  |          | 5 | 
|1.1    Net Reserves         |  |          | 5 | 
|1.2    Gross Volumes        |  |          | 5 | 
|1.3    Net Present Values   |  |          | 6 | 
|1.4    Sensitivity Analysis |  |          | 7 | 
|2.    BASIS OF OPINION      |  |          | 7 | 
|                            | 
|APPENDIX                    |  |          |   | 
|I.    Glossary              |  |          |   | 



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| |  |                                                                                                                                      
| |  | -------------------------------------------------------------------------------------------------------------------------------------
| |  | LOGO                                                                                                                                 
| |  | Gaffney, Cline & Associates (Consultants) Pte. Ltd. 80 Anson Road
#31-01C Fuji Xerox Towers
Singapore 079907 Telephone: +65 6225
6951
| | 
| |  | www.gaffney-cline.com                                                                                                                



|                                  |  |               
|--------------------------------- |  | --------------
|DSR/dh/L0168/2012/KK1815 & KK1816 |  | 3rdApril, 2012

PetroChina Company Limited

9 Dongzhimen North Street, Dongcheng District

Beijing 100007

China

Dear Gentlemen,

THIRD PARTY REPORT

RESERVES ESTIMATION AND VALUATION OF

(CHAD AND KAZAKHSTAN 
PKKR & KOLZHAN)

AS OF 31stDECEMBER, 2011

INTRODUCTION

Gaffney, Cline & Associates (GCA) was requested by China National Oil and Gas Exploration and
Development Corporation International Holding Ltd. (CNODCI), to conduct reserves estimation and valuation (as of 31stDecember, 2011) of selected petroleum assets in Chad and Venezuela, in which CNODCI has current interests. The
SEC Executive and SEC Technical Reports were submitted to CNODCI in January and February, 2012, respectively.

At about the same time with the above project preparation, GCA was requested by PetroKazakhstan Inc (PKI) to conduct reserves estimation and evaluation (as of 31stDecember, 2011) of selected petroleum assets in Kazakhstan, in
which PKI has current interests. The Kazakhstan assets cover five subsidiaries involved in oil and gas exploration and production under PKI  JSC PetroKazakhstan Kumkol Resources (PKKR), JSC Turgai Petroleum (TP), JSC Kazgermunai (KGM),
PetroKazakhstan Ventures Inc. (PKVI) and Kolzhan LLP (Kolzhan).

Related to the Kazakhstan Project, PKI requested GCA to
prepare a third party report for CNODCI. The third party report is required since PKI is an integrated oil and gas company owned by CNODCI and JSC KazMunaiGas Exploration Production (KMG EP). CNODCI holds 67% Wl and KMG EP 33% Wl in PKI; therefore,
indirectly CNODCI holds interest in the assets owned by PKI. The Third Party Reports on Kazakhstan assets (SEC Executive and SEC Technical) were submitted to PKI and CNODCI in February, 2012, respectively.

Recently, CNODCI requested GCA to prepare a Third Party Report intended to be submitted to PetroChina Company Limited
(PetroChina). This report is to summarize the results of reserves estimation and valuation as of 31stDecember, 2011 as mentioned above of only selected petroleum assets. The selected petroleum assets determined by CNODCI are in Chad and Kazakhstan (PKKR & Kolzhan).



UEN:
198701453N



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PetroChina (Third Party Report) |  | LOGO



METHODOLOGY

In carrying out the review, GCA relied upon information and data provided either through CNODCI or PKI (for PKKR & Kolzhan assets), which comprised: basic engineering data; geoscience information
and engineering interpretations associated with such data; other technical reports; costs and commercial data; and development plans. The available data and interpretations were reviewed for reasonableness and the latter adjusted where appropriate.

The results presented in this report are based upon information and data made available to GCA on or
before 16thDecember, 2011. The Reserve Estimates,
forward production estimates and Net Present Value (NPV) computations as presented herein are based upon these data and represent GCAs opinion as of 31stDecember, 2011.

It is GCAs considered opinion that the estimates of oil and gas reserve volumes as of 31stDecember, 2011, presented in this document are, in aggregate, reasonable and were prepared in accordance with the
Final Rule of Modernization of Oil and Gas Reporting (17 CFR Parts 210, 211, 229 and 249) published by the US Securities and Exchange Commission (SEC) on 14thJanuary, 2010 on Federal Register/ Vol. 74, No. 9 (see web version:
http://www.sec.gov/rules/final/2010/33-8995fr.pdf). The definitions are applicable to the Proved reserve categories and sub-classifications.

Economic models were constructed based on terms of the applicable petroleum contracts as provided by CNODCI or PKI, in order to calculate CNODCIs net revenue interest Proved reserves. As of
31stDecember, 2011, all Proved SEC reserves were
allocated up to the end of the license contract period only.

As per SEC guidelines, the oil prices which were used in the
evaluation are the unweighted 12-month arithmetic averages of the first-day-of-the month price for each month within the 12-month period (January to December, 2011) prior to the end of reporting period, unless prescribed by contract. Those prices
were not escalated throughout the evaluation period except where alternate prices are prescribed by contract. The report also summarises the sensitivity results in which oil prices were escalated throughout the evaluation period except as prescribed
by contract. The historical 12-month oil prices were supplied by CNODCI or PKI.

Future capital costs were derived from
development program forecasts prepared by CNODCI or PKI for each production unit and corresponding recent historical unit cost data. The recent historical cost data for each relevant production unit were utilized to determine current operating cost
conditions. These costs were not escalated throughout the evaluation period in the Base Case; however the future capital and Operating Costs were escalated in the sensitivity analysis.

CNODCIs net reserve volumes are derived by converting calculated net revenues accruing to CNODCI under the terms of the relevant
petroleum contract into equivalent barrels of oil utilising the average 2011 oil pricing explained above. The CNODCI net revenue interest volumes reported in this document represent those amounts that are determined to be attributable to
CNODCIs net economic interest after the deduction of amounts attributable to third parties (government and other working interest partners).

Net Present Value (NPV) computations were also undertaken and derived using cost and production profiles input to the various economic models established for the different petroleum contracts.
These NPVs represent future net revenue, after taxes, attributable to the interests of CNODCI, discounted over the economic life of the project at a specified discount rate to a present value as of 31stDecember, 2011. NPV results are also presented for the
sensitivity analysis using the escalated oil and gas prices and Capital and Operating Costs. Unless otherwise stated, no opening tax positions were considered.

A glossary of abbreviations and key industry standard terms, some or all of which may be used in this report, is attached as Appendix I.



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|1. | RESULTS SUMMARY
|-- | ---------------



|1.1 | Net Reserves
|--- | ------------

The
following tables present the net entitlement Proved Developed, Proved Undeveloped and Total Proved oil reserves attributable to CNODCIs working interests (Wl) estimated in accordance with SEC guidelines.

As required under SEC guidelines, these estimates were prepared under the prevailing fiscal terms and exclude any government share. The
economic cut offs were applied using costs and prices which are unescalated throughout the period of calculation, except where alternate prices are prescribed by contract. The oil prices used for these computations were the un-weighted 12-month
arithmetic average of the first-day-of-the month price for each month within the 12-month period (January to December, 2011).

NET ENTITLEMENT PROVED OIL RESERVES

AS OF 31stDECEMBER, 2011



|                    |  |                 |        |  |                   |  |        |             |  |  |         | 
|------------------- |  | --------------- | ------ |  | ----------------- |  | ------ | ----------- |  |  | ------- | 
|Country             |  | ProvedDeveloped |        |  | ProvedUndeveloped |  |        | TotalProved | 
|                    |  | (Mstb)          |        |  | (Mstb)            |  |        | (Mstb)      | 
|CHAD                |  |                 | 29,306 |  |                   |  |       |             |  |  | 29,306  | 
|KAZAKHSTAN          |  |                 |        |  |                   |  |        |             |  |  |         | 
|PKKR                |  |                 | 49,433 |  |                   |  | 6,550  |             |  |  | 55,982  | 
|Kolzhan             |  |                 | 4.721  |  |                   |  | 10,471 |             |  |  | 15,193  | 
|                    |  |                 |        |  |                   |  |        |             |  |  |         | 
|Subtotal Kazakhstan |  |                 | 54,754 |  |                   |  | 17,021 |             |  |  | 71,175  | 
|                    |  |                 |        |  |                   |  |        |             |  |  |         | 
|TOTAL CNODCI        |  |                 | 83,460 |  |                   |  | 17,021 |             |  |  | 100,481 | 
|                    |  |                 |        |  |                   |  |        |             |  |  |         | 

Notes:

|1. | Royalty is paid in kind in Chad
|-- | -------------------------------

|2. | Totals may not add exactly due to rounding errors.
|-- | --------------------------------------------------



|1.2 | Gross Volumes
|--- | -------------

Gross production volumes are presented for reference information only. They represent a 100% working interest in commercially recoverable
volumes, i.e. after economic cutoffs have been applied. Gross volumes include volumes attributable to third parties, government and other working interest partners.

GROSS PROVED OIL RESERVES

AS OF 31stDECEMBER, 2011



|                    |  |                 |         |  |                   |  |        |             |  |  |         | 
|------------------- |  | --------------- | ------- |  | ----------------- |  | ------ | ----------- |  |  | ------- | 
|Country             |  | ProvedDeveloped |         |  | ProvedUndeveloped |  |        | TotalProved | 
|                    |  | (Mstb)          |         |  | (Mstb)            |  |        | (Mstb)      | 
|CHAD                |  |                 | 33,492  |  |                   |  |       |             |  |  | 33,492  | 
|KAZAKHSTAN          |  |                 |         |  |                   |  |        |             |  |  |         | 
|PKKR                |  |                 | 73,780  |  |                   |  | 9,775  |             |  |  | 83,556  | 
|Kolzhan             |  |                 | 7,057   |  |                   |  | 15,629 |             |  |  | 22,686  | 
|                    |  |                 |         |  |                   |  |        |             |  |  |         | 
|Subtotal Kazakhstan |  |                 | 80,837  |  |                   |  | 25,404 |             |  |  | 106,242 | 
|                    |  |                 |         |  |                   |  |        |             |  |  |         | 
|TOTAL CNODCI        |  |                 | 114,329 |  |                   |  | 25,404 |             |  |  | 139,734 | 
|                    |  |                 |         |  |                   |  |        |             |  |  |         | 

Note:    Totals may not add exactly due to rounding errors.



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PetroChina (Third Party Report) |  | LOGO





|1.3 | Net Present Values
|--- | ------------------

The NPVs as of 31st December, 2011 of estimated cash flows discounted at 10%, after taxes, attributable to CNODCIs working
interest in the projects identified above (excluding any balance sheet adjustments or financing costs), are summarised below.

NET PRESENT VALUES ATTRIBUTABLE TO CNODCI

AS OF 31st DECEMBER, 2011

DISCOUNT RATE 10%



|                    |  |                  |       |  |                   |  |     |              |  |  |       | 
|------------------- |  | ---------------- | ----- |  | ----------------- |  | --- | ------------ |  |  | ----- | 
|Country             |  | Proved Developed |       |  | ProvedUndeveloped |  |     | Total Proved | 
|                    |  | (U.S.$ MM)       |       |  | (U.S.$ MM)        |  |     | (U.S.$ MM)   | 
|CHAD                |  |                  | 469   |  |                   |  |    |              |  |  | 469   | 
|Kazakhstan          |  |                  |       |  |                   |  |     |              |  |  |       | 
|PKKR                |  |                  | 872   |  |                   |  | 83  |              |  |  | 956   | 
|Kolzhan             |  |                  | 77    |  |                   |  | 150 |              |  |  | 227   | 
|                    |  |                  |       |  |                   |  |     |              |  |  |       | 
|Subtotal Kazakhstan |  |                  | 949   |  |                   |  | 234 |              |  |  | 1,183 | 
|                    |  |                  |       |  |                   |  |     |              |  |  |       | 
|TOTAL CNODCI        |  |                  | 1,418 |  |                   |  | 234 |              |  |  | 1,652 | 
|                    |  |                  |       |  |                   |  |     |              |  |  |       | 

Notes:

|1. | No opening tax positions or un-recovered balances are available.
|-- | ----------------------------------------------------------------

|2. | Totals may not add exactly due to rounding errors.
|-- | --------------------------------------------------

The NPVs were calculated on the basis of SEC guidelines under which the economic cut-offs were applied using unescalated costs and constant prices. The crude oil prices used for these computations were
the un-weighted 12-month arithmetic average of the first-day-of-the month price for each month within the 12-month period (January to December, 2011) except in instances where alternate prices are prescribed by contract.



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|1.4 | Sensitivity Analysis
|--- | --------------------

Sensitivity analysis has been carried out on the oil prices. In the sensitivity analysis, oil prices were escalated throughout the evaluation period except prescribed by contract. In addition to the
escalated oil prices, CAPEX and OPEX were escalated. The sensitivity results are summarised on the following.

NET PRESENT
VALUES ATTRIBUTABLE TO CNODCI

SENSITIVITY RESULTS

AS OF 31stDECEMBER, 2011

DISCOUNT RATE 10%



|                    |  |                  |       |  |                   |  |     |              |  |  |       | 
|------------------- |  | ---------------- | ----- |  | ----------------- |  | --- | ------------ |  |  | ----- | 
|Country             |  | Proved Developed |       |  | ProvedUndeveloped |  |     | Total Proved | 
|                    |  | (U.S.$ MM)       |       |  | (U.S.$ MM)        |  |     | (U.S.$ MM)   | 
|CHAD                |  |                  | 469   |  |                   |  |    |              |  |  | 469   | 
|KAZAKHSTAN          |  |                  |       |  |                   |  |     |              |  |  |       | 
|PKKR                |  |                  | 770   |  |                   |  | 70  |              |  |  | 840   | 
|Kolzhan             |  |                  | 68    |  |                   |  | 131 |              |  |  | 199   | 
|                    |  |                  |       |  |                   |  |     |              |  |  |       | 
|Subtotal Kazakhstan |  |                  | 838   |  |                   |  | 200 |              |  |  | 1,039 | 
|                    |  |                  |       |  |                   |  |     |              |  |  |       | 
|TOTAL CNODCI        |  |                  | 1,307 |  |                   |  | 200 |              |  |  | 1,508 | 
|                    |  |                  |       |  |                   |  |     |              |  |  |       | 

Notes:

|1. | No sensitivity analysis has been carried out in Chad since currently CNODCI receives the constant price of U.S.$68/bbl as prescribed by the contract with Chad
Government.
|-- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------

|2. | No opening tax positions or un-recovered balances are available.
|-- | ----------------------------------------------------------------

|3. | Totals may not add exactly due to rounding errors.
|-- | --------------------------------------------------



|2. | BASIS OF OPINION
|-- | ----------------

This
report has been compiled under the supervision of Mr. David S. Ahye. Mr. Ahye is a Principal Advisor for the Asia Pacific region, based in Singapore. He has over 30 years experience in the petroleum industry and has managed
numerous reserves certification audits. Mr. Ahye holds a Bachelors Degree (Honours) in Chemical Engineering.

This
assessment was conducted within the context of GCAs understanding of the effects of petroleum legislation, taxation and other regulations that currently pertain to the various properties. However, GCA is not in a position to attest to the
property title, financial interest relationships or encumbrances thereon for any part of the properties reviewed.

It should
be understood that any evaluation, particularly one involving future petroleum developments, may be subject to significant variations over short periods of time, as new information becomes available and perceptions change.



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GCA acted as independent reserve auditors. The management and employees of GCA have no direct or indirect interest holding in either
CNODCI/PKI/PetroChina or its affiliated companies. GCAs remuneration was not in any way contingent upon reported reserve estimates. No representations are made herein in respect of property title or encumbrances thereon. The economic analyses
presented have been utilized solely for the calculation of net reserves and do not represent assessments of market value. This report has been prepared for PetroChina and should not be used for purposes other than those for which it is intended.

Yours faithfully,

GAFFNEY, CLINE & ASSOCIATES (CONSULTANTS) PTE LTD



LOGO

David S. Ahye

Principal



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APPENDIX I

GLOSSARY



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List of Standard Oil Industry Terms and Abbreviations



|                |  |                                        |  |        |  |                                  
|--------------- |  | -------------------------------------- |  | ------ |  | ---------------------------------
|ABEX            |  | Abandonment Expenditure                |  | DWT    |  | Dead-weight ton                  
|ACQ             |  | Annual Contract Quantity               |  | E&A    |  | Exploration & Appraisal          
|°API            |  | Degrees API (American                  |  | E&P    |  | Exploration and Production       
|                |  | Petroleum Institute)                   |  | EBIT   |  | Earnings before Interest and Tax 
|AAPG            |  | American Association of Petroleum      |  | EBITDA |  | Earnings before interest, tax,   
|                |  | Geologists                             |  |        |  | depreciation and amortisation    
|AVO             |  | Amplitude versus Offset                |  | El     |  | Entitlement Interest             
|A$              |  | Australian Dollars                     |  | EIA    |  | Environmental Impact Assessment  
|B               |  | Billion (109)                          |  | EOR    |  | Enhanced Oil Recovery            
|Bbl             |  | Barrels                                |  | EUR    |  | Estimated Ultimate Recovery      
|/Bbl            |  | per barrel                             |  | EMV    |  | Expected Monetary Value          
|Bbbl            |  | Billion Barrels                        |  | FDP    |  | Field Development Plan           
|BHA             |  | Bottom Hole Assembly                   |  | FEED   |  | Front End Engineering and Design 
|BHC             |  | Bottom Hole Compensated                |  | FPSO   |  | Floating Production, Storage and 
|Bscf or Bcf     |  | Billion standard cubic feet            |  |        |  | Offloading                       
|Bscf/d or Bcf/d |  | Billion standard cubic feet per day    |  | FSO    |  | Floating Storage and Offloading  
|Bm3             |  | Billion cubic metres                   |  | ft     |  | Foot/feet                        
|bcpd            |  | Barrels of condensate per day          |  | Fx     |  | Foreign Exchange Rate            
|BHP             |  | Bottom Hole Pressure                   |  | g      |  | gram                             
|blpd            |  | Barrels of liquid per day              |  | g/cc   |  | grams per cubic centimetre       
|bpd             |  | Barrels per day                        |  | gal    |  | gallon                           
|boe             |  | Barrels of oil equivalent @xxx mcf/bbl |  | gal/d  |  | gallons per day                  
|boepd           |  | Barrels of oil equivalent per day@     |  | G&A    |  | General and Administrative costs 
|                |  | xxx mcf/bbl                            |  | GBP    |  | Pounds Sterling                  
|BOP             |  | Blow Out Preventer                     |  | GDT    |  | Gas Down to                      
|bopd            |  | Barrels oil per day                    |  | GIIP   |  | Gas initially in place           
|bwpd            |  | Barrels of water per day               |  | Gj     |  | Gigajoules (one billion Joules)  
|BS&W            |  | Bottom sediment and water              |  | GOR    |  | Gas Oil Ratio                    
|BTU             |  | British Thermal Units                  |  | GTL    |  | Gas to Liquids                   
|bwpd            |  | Barrels water per day                  |  | GWC    |  | Gas water contact                
|CBM             |  | Coal Bed Methane                       |  | HDT    |  | Hydrocarbons Down to             
|CO2             |  | Carbon Dioxide                         |  | HSE    |  | Health, Safety and Environment   
|CAPEX           |  | Capital Expenditure                    |  | HSFO   |  | High Sulphur Fuel Oil            
|CCGT            |  | Combined Cycle Gas Turbine             |  | HUT    |  | Hydrocarbons up to               
|cm              |  | centimetres                            |  | H2S    |  | Hydrogen Sulphide                
|CMM             |  | Coal Mine Methane                      |  | IOR    |  | Improved Oil Recovery            
|CNG             |  | Compressed Natural Gas                 |  | IPP    |  | Independent Power Producer       
|Cp              |  | Centipoise (a measure of viscosity)    |  | IRR    |  | Internal Rate of Return          
|CSG             |  | Coal Seam Gas                          |  | J      |  | Joule (Metric measurement of     
|CT              |  | Corporation Tax                        |  |        |  | energy. 1 kilojoule = 0.9478 BTU)
|Cum             |  | Cumulative                             |  | k      |  | Permeability                     
|DCQ             |  | Daily Contract Quantity                |  | KB     |  | Kelly Bushing                    
|Deg C           |  | Degrees Celsius                        |  | KJ     |  | Kilojoules (one Thousand Joules) 
|Deg F           |  | Degrees Fahrenheit                     |  | kl     |  | Kilolitres                       
|DHI             |  | Direct Hydrocarbon Indicator           |  | km     |  | Kilometres                       
|DST             |  | Drill Stem Test                        |  | km2    |  | Square kilometres                



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|                    |  |                                                               |  |               |  |                                          
|------------------- |  | ------------------------------------------------------------- |  | ------------- |  | -----------------------------------------
|kPa                 |  | Thousands of Pascals measurement                              |  | p.a.          |  | Per annum                                
|                    |  | of pressure)                                                  |  | Pa            |  | Pascals (metric measurement of
pressure) 
|KW                  |  | Kilowatt                                                      |  | P&A           |  | Plugged and Abandoned                    
|KWh LKG             |  | Kilowatt hour Lowest Known
Gas                                |  | PD            |  | Proved Developed                         
|LKH                 |  | Lowest Known Hydrocarbons                                     |  | PDP           |  | Proved Developed Producing               
|LKO                 |  | Lowest Known Oil                                              |  | PDNP          |  | Proved Developed Non-producing           
|LNG                 |  | Liquefied Natural Gas                                         |  | PI            |  | Productivity Index                       
|LoF                 |  | Life of Field                                                 |  | PJ            |  | Petajoules(1015Joules)                   
|LPG                 |  | Liquefied Petroleum Gas                                       |  | PSDM          |  | Post Stack Depth Migration               
|LTI                 |  | Lost Time Injury                                              |  | psi           |  | Pounds per square inch                   
|LWD                 |  | Logging while drilling                                        |  | psia          |  | Pounds per square inch absolute          
|m                   |  | Metres                                                        |  | psig          |  | Pounds per square inch gauge             
|M                   |  | Thousand                                                      |  | PUD           |  | Proved Undeveloped                       
|m3                  |  | Cubic metres                                                  |  | PVT           |  | Pressure volume temperature              
|Mcf or Mscf         |  | Thousand standard cubic feet                                  |  | P10           |  | 10% Probability                          
|MCM                 |  | Management Committee Meeting                                  |  | P50           |  | 50% Probability                          
|mD                  |  | Measure of Permeability in                                    |  | P90           |  | 90% Probability                          
|                    |  | millidarcies                                                  |  | RF            |  | Recovery factor                          
|MD                  |  | Measured Depth                                                |  | RFT           |  | Repeat Formation Tester                  
|MDT                 |  | Modular Dynamic Tester                                        |  | RT            |  | Rotary Table                             
|Mean                |  | Arithmetic average of a set of                                |  | Rw            |  | Resistivity of water                     
|                    |  | numbers                                                       |  | SCAL          |  | Special core analysis                    
|Median              |  | Middle value in a set of values                               |  | cf or scf     |  | Standard Cubic Feet                      
|MFT                 |  | Multi Formation Tester                                        |  | cf/d or scf/d |  | Standard Cubic Feet per day              
|mg/l                |  | milligrames per litre                                         |  | scf/ton       |  | Standard cubic foot per ton              
|MJ                  |  | Megajoules (One Million Joules)                               |  | SL            |  | Straight line (for depreciation)         
|Mm3                 |  | Thousand Cubic metres                                         |  | So            |  | Oil Saturation                           
|Mm3d                |  | Thousand Cubic metres per day                                 |  | SPE           |  | Society of Petroleum Engineers           
|MM                  |  | Million                                                       |  | SPEE          |  | Society of Petroleum Evaluation Engineers
|MMbbl               |  | Millions of barrels                                           |  | ss            |  | Subsea                                   
|MMBTU
MMcf or MMscf |  | Millions of British Thermal Units Million standard cubic feet |  | stb           |  | Stock tank barrel                        
|MMstb               |  | Millions of Stock tank barrel                                 |  | STOIIP        |  | Stock tank oil initially in place        
|Mode                |  | Value that exists most frequently in                          |  | Sw            |  | Water Saturation                         
|                    |  | a set of values = most likely                                 |  | T             |  | Tonnes                                   
|Mscf/d              |  | Thousand standard cubic feet per                              |  | TD            |  | Total Depth                              
|                    |  | day                                                           |  | Te            |  | Tonnes equivalent                        
|MMscf/d             |  | Million standard cubic feet per day                           |  | THP           |  | Tubing Head Pressure                     
|MW                  |  | Megawatt                                                      |  | TJ            |  | Terajoules (1012Joules)                  
|MWD                 |  | Measuring While Drilling                                      |  | Tscf or Tcf   |  | Trillion standard cubic feet             
|MWh                 |  | Megawatt hour                                                 |  | TCM           |  | Technical Committee Meeting              
|mya                 |  | Million years ago                                             |  | TOC           |  | Total Organic Carbon                     
|NGL                 |  | Natural Gas Liquids                                           |  | TOP           |  | Take or Pay                              
|N2                  |  | Nitrogen                                                      |  | Tpd           |  | Tonnes per day                           
|NPV                 |  | Net Present Value                                             |  | TVD           |  | True Vertical Depth                      
|OBM                 |  | Oil Based Mud                                                 |  | TVDss         |  | True Vertical Depth Subsea               



AI.2



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##### Table of Contents

|                                                                  |  |     
|----------------------------------------------------------------- |  | ----
|DSR/dh/L0168/2012/KK1815 & KK1816
PetroChina (Third Party Report) |  | LOGO



|      |  |                               |  |      |  |                                                    
|----- |  | ----------------------------- |  | ---- |  | ---------------------------------------------------
|OCM   |  | Operating Committee Meeting   |  | USGS |  | United States Geological Survey                    
|ODT   |  | Oil down to                   |  |      |  |                                                    
|OPEX  |  | Operating Expenditure         |  |      |  |                                                    
|OWC   |  | Oil Water Contact             |  |      |  |                                                    
|U.S.$ |  | United States Dollar          |  | 2Q06 |  | Second quarter (3 months) of 2006 (example of date)
|VSP   |  | Vertical Seismic Profiling    |  |      | 
|WC    |  | Water Cut                     |  | 2D   |  | Two dimensional                                    
|Wl    |  | Working Interest              |  | 3D   |  | Three dimensional                                  
|WPC   |  | World Petroleum Council       |  | 4D   |  | Four dimensional                                   
|WTI   |  | West Texas Intermediate       |  | 1P   |  | Proved Reserves                                    
|wt%   |  | Weight percent                |  | 2P   |  | Proved plus Probable Reserves                      
|1H05  |  | First half (6 months) of 2005 |  | 3P   |  | Proved plus Probable plus                          
|      |  | (example of date)             |  |      |  | Possible Reserves                                  
|      |  |                               |  | %    |  | Percentage                                         



AI.3