Unassociated Document


    Exhibit
10.2

    


    ENGLISH TRANSLATION — EXECUTED
DOCUMENT IS IN SPANISH

    


    AMENDMENT
NO.1 TO THE CONTRACT RESULTING FROM THE ACCEPTANCE OF THE COMMERCIAL OFFER DATED
DECEMBER 17, 2009 FOR THE PURCHASE OF CHAZA OIL

    


    The
contracting parties: ECOPETROL
S.A., decentralized entity of national order, incorporated by means of
Law 165 of 1948, with Tax ID No.  899-999-068-1, organized as a Mixed
Economy Company according to the dispositions of article No. 2 of Law 1118 of
2006, linked/related to the Ministry of Mines and Energy, with domicile in
Bogota D.C., whose bylaws are totally contained in Public Deed No. 5314 of
December 14, 2007 given before Notary Second of Bogota D.C. and registered
before the Chamber of Commerce, hereinafter referred in this Amendment as THE
BUYER,  represented by CLAUDIA L. CASTELLANOS R., of age and domiciled
in this city, identified with citizenship card No. 63.314.635 issued in
Bucaramanga, who in capacity of Vice-president of Supply and Marketing and with
authorization contained in the Delegation Manual, acts on behalf of this
company, and on the other hand, GRAN TIERRA ENERGY COLOMBIA
LTD, with Tax Id No. 860.516.431-7, hereinafter THE SELLER represented by
JULIAN GARCIA SALCEDO, identified with citizenship card No. 19.421.914 who acts
in his capacity as legal representative and is duly authorized to execute this
Amendment according to the incorporation and representation certificate issued
by the Chamber of Commerce,  who states that neither he nor the
company he represents are disqualified on grounds of disability or any
inconsistency according to the Constitution or the law, that might prevent them
from entering into this Amendment.

    


    In the
conditions listed, THE BUYER and THE SELLER, who jointly and individually will
be referred to as the Parties or the Party, agree to execute this Amendment to
the contract resulting from the acceptance by GRAN TIERRA ENERGY COLOMBIA LTD of
the commercial offer dated December 17 2009 for the purchase of crude oil
produced in Chaza Block, taking into account the following:

    


    CONSIDERATIONS

    


    
      	
              1.  

            	
              That
      by means of Purchase Order No. SOL-01-2009 issued on December 18, 2009
      GRAN TIERRA ENERGY COLOMBIA LTD accepted the Commercial Offer dated
      December 17, 2009 issued by ECOPETROL S.A., for the purchase of 100% of
      the crude oil of property of THE SELLER, produced in Chaza
      Block.

            


    

    


    
      	
              2.  

            	
              That
      the expiration date for the contract resulting from the acceptance of the
      Commercial Offer dated December 17, 2009 for the purchase of crude oil is
      December 31st, 2010.

            


    

    


    
      	
              3.  

            	
              That
      THE SELLER has expressed its interest in selling to third parties
      different from THE BUYER a portion of the crude oil produced in Chaza
      Block.

            


    

    


    
      	
              4.  

            	
              That
      ECOPETROL S.A. has no objection with THE SELLER commercializing a part of
      the crude oil produced in the Chaza Block with third parties, provided
      that The SELLER complies with the strict delivery to ECOPETROL S.A. of the
      volumes according to the final schedule approved by THE BUYER according to
      the provisions contained in CLAUSE TWO – PROGRAM SCHEDULE of this
      document.

            


    

    


    
      	
              5.  

            	
              Taking
      into account the above, ECOPETROL and GRAN TIERRA ENERGY COLOMBIA LTD
      require to enter into an Amendment by means of which the purpose of the
      contract is modified, allowing THE SELLER to commercialize with third
      parties other than ECOPETROL SA part of the crude oil produced in the
      Chaza Block.

            


    

     

    
      
         

      

      
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              6.  

            	
              That
      for purposes of the execution of this Amendment, THE BUYER previously
      verified the Bulletin of Fiscal Responsibility developed and published by
      the General Comptroller of the Republic, in which THE SELLER does not
      appear as one of the people who have been determined by a judicial and
      firm decision as fiscally responsible. Additionally, THE BUYER implemented
      the control mechanisms in relation to the prevention of money laundering,
      and developed the appropriate tools for implementing such mechanisms,
      pursuant to the general policy for the prevention and control of money
      laundering

            


    

    


    
      	
              7.  

            	
              That
      in accordance with the Delegations Manual, the Vice-President of Supply
      and Marketing is competent to enter into this
  Amendment.

            


    

    


    
      	
              8.  

            	
              That
      in accordance with the dispositions contained in the Contracting Manual of
      THE BUYER and having analyzed the nature and manner of implementing the
      performance of the Parties on the occasion of this Amendment to the sales
      of crude oil, the Authorized Officer has classified the risk as low, and
      therefore dispenses the need to require a guarantee from THE
      SELLER.

            


    

    


    
      	
              9.  

            	
              That
      considering the contractual planning, the areas of Labor Relations Risk,
      Coordination of Risks, Coordination of Budget and Accounting and Tax
      Coordination of ECOPETROL S.A. were consulted, in order to avoid any
      labor, tax, environmental, and other risks that may be generated for
      Ecopetrol as a result of the execution and implementation of this
      Amendment.

            


    

    


    
      	
              10.  

            	
              That
      the Contract Administrator, after support it before the Manager, has
      recommended that the Authorized Official sign this
    document.

            


    

    


    
      	
              11.  

            	
              That
      in compliance with the policy for preventing of money laundering and
      terrorist financing adopted by THE BUYER, the legal representative of THE
      SELLER declares under oath, subject to the penalties provided in the Penal
      Code:

            


    

    


    
      	
              a.  

            	
              That
      my resources (or the resources of the institution that I represent) come
      from lawful activities and are linked to the normal development of my
      activities (or the activities contained in the purpose of the company I
      represent), and that, in the same sense, such resources do not come from
      any unlawful activity contained in the Colombian Criminal Code or any law
      that substitutes, amends or modifies it.

               

              That I (or the entity I represent) have not
      made transactions or operations destined to illicit activities referred to
      in the Colombian Criminal Code or any law that substitutes, amends or
      modifies it, or to people connected with such
  activities.

            


    

    


    
      
         

      

      
        2

        
          

        

      

      
         

      

    

     

    
      	
              b.  

            	
              That
      the resources compromised to the contract or legal relationship with THE
      BUYER do not come from any unlawful activity referred to in the Colombian
      Criminal Code or any law that substitutes, amends or modifies
      it.

               

              That in the execution of the contract or legal
      relationship with THE BUYER, I will not hire or have links to third
      parties that perform operations or whose resources come from illicit
      activities referred to in the Colombian Criminal Code or any law that
      substitutes, amends or modifies it.

            


    

    


    
      	
              c.  

            	
              That
      the institution I represent complies with the regulations on the
      prevention and control money laundering and terrorist financing (ML / FT)
      that are applicable (if any), having implemented the policies, procedures
      and mechanisms to prevent and control of ML/FT arising from such laws.
      Certification model is attached in Annex 1.

               

              That neither I nor the institution I represent,
      or its shareholders, partners or associates that directly or indirectly
      have FIVE PERCENT (5%) or more of the capital, contribution or
      participation, legal representatives and members of the Board of
      Directors, are on international lists binding for Colombia under
      international law (United Nations lists) or in OFAC lists, being THE BUYER
      is entitled to check if it deems appropriate and to terminate any business
      or legal relationship if it verifies that any of those people are on these
      lists. Certification model is attached in Annex
  2.

            


    

    


    
      	
              d.  

            	
              That
      there is not against me or the entity I represent and its shareholders,
      associates or partners that directly or indirectly have the FIVE PERCENT
      (5%) or more of the capital, contribution or participation, their legal
      representatives and members of the Board Directors,
      any  investigations or criminal proceedings for a felony, THE
      BUYER is entitled to check if it deems appropriate in databases or in
      national or international public information and to terminate any legal
      relationship if it verifies that any of those people have investigations
      or proceedings or have information is such public databases that may place
      THE BUYER in legal or reputational
risk.

            


    

    


    
      	
              e.  

            	
              That
      in the event that any of the circumstances described in the preceding two
      paragraphs, I agree to immediately notify THE
  BUYER.

            


    

    


    
      	
              f.  

            	
              That
      with the signature of this document it is understood that I as well as the
      person or legal entity that I represent, give our informed consent, and
      therefore authorize THE BUYER to inform national authorities of any
      country in which THE BUYER performs operations about any of the situations
      described herein, and to provide to the relevant authorities of those
      countries, all personal information, public, private or semiprivate that
      about me or the person or company I represent, they require. Also, for THE
      BUYER to report to the relevant authorities, taking into account its rules
      and manuals related to its system of prevention and / or management of
      risk of money laundering and terrorist financing, exonerating it from any
      liabilities derived from said act.

            


    

    


    
      	
              g.  

            	
              That
      all documents and information provided for the conclusion and execution of
      the contract or legal transaction with THE BUYER is truthful and accurate,
      being THE BUYER entitled to verify if it deems appropriate and to
      terminate the contract or legal transaction, if verified, or has knowledge
      that it is not so.

            


    

    


    
      	
              h.  

            	
              Than
      any other person or legal entity has illegitimate interest in the contract
      or legal transaction that encourages the execution of this
      declaration.

            


    

    


    
      	
              i.  

            	
              That
      I am aware, declare and accept that THE BUYER is under a legal obligation
      to seek clarification as it considers appropriate in the event that
      circumstances arise on the basis in which THE BUYER may have reasonable
      doubts about my operations or the operations of the person or legal entity
      I represent, as well as the origin of our assets, event in which we commit
      to provide the corresponding clarifications. If these are not
      satisfactory, according to THE BUYER, we authorize to terminate any legal
      or business relationship.

            


    

     

    Taking
into account the above, the Parties

     

    
      
         

      

      
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    AGREE

    


    FIRST CLAUSE. Modify article
No. 1 (SOURCES OF SUPPLY AND VOLUME) of the contract resulting from the
acceptance of the Commercial Offer dated December 17, 2009 accepted by means of
Purchase Order No. SOL-01-2009 issued on December 18, 2009, as
follows:

    


    “1.
SOURCES OF SUPPLY AND VOLUME

    


    THE BUYER
agrees to acquire ninety percent (90%) of the volume of crude produced and which
is property of THE SELLER in Chaza Block, and THE SELLER agrees to sell and
deliver a volume equivalent to ninety percent (90%) of crude oil of its property
of the production of Chaza Block. The contract resulting from acceptance of the
commercial offer does not include the volume of crude oil which is owned by the
National Hydrocarbons Agency (ANH) corresponding to royalties.

    


    The
obligations of THE BUYER and THE SELLER will last during the term set forth in
article No. 4 of the present document.

    


    For
purposes of this commercial offer and the contract arising from acceptance of
it, one barrel equals to one hundred and fifty-eight point nine hundred
eighty-eight (158.988) liters.

    


    FIRST PARAGRAPH: DESTINATION
OF CRUDE OIL. THE BUYER will destine the oil purchase for exportation through
the port of Tumaco. THE BUYER, upon prior written notice to THE SELLER may
allocate additional crude oil subject to the present crude oil purchase for
refinery in the country.

    


    SECOND CLAUSE. Modify article
No. 7 (DELIVERY PROGRAM) of the contract resulting from the
acceptance of the Commercial Offer dated December 17, 2009 accepted by means of
Purchase Order No. SOL-01-2009 issued on December 18, 2009, as
follows:

    


    “7. DELIVERY PROGRAM: THE
SELLER shall deliver THE BUYER not later than the third day (03) calendar day of
each month copies of the nomination of delivery for the following trimester. The
final volume to receive by THE BUYER at the point of delivery defined in the
article No. 6 shall be drawn up every month in accordance to the final schedule
made by THE BUYER in accordance with paragraph first and second of article No.
six, and returned to THE SELLER before the tenth (10) calendar day of each
month.

    


    Given
that the above information is the basic premise for the planning process of THE
BUYER, the latter may refrain from receiving the crude oil if THE SELLER does
not provide the program within the established deadline.

    


    THE
SELLER is obliged to provide and carry information from the field on production,
liquidation of royalties, shipping by trucks (carrrotanque) and/or pipeline
indicating the participation and ownership of each and the official receipt in
the receipt station. To this end, THE BUYER shall send to THE SELLER daily
information requested through the volumetric integrator available via the
website, which’s User Manual is attached as Annex 1.

    


    FIRST PARAGRAPH: Without
prejudice of the dispositions contained in article No. 15 (ACTS OF GOD AND
EXCULPATORY EVENTS), shall be considered exculpatory events: 1. In the event
that within the agreed period THE BUYER cannot receive the entire crude oil
delivery at the Delivery Point, it shall inform THE SELLER with a minimum of
three (3) calendar days and as soon the contingency is overcome it shall
announce the date for the reactivation of the receipts. 2. Additionally, in the
event that for reasons specifically related to the operation of the field, THE
SELLER cannot deliver to THE BUYER the crude oil in any of the dates specified
in the program, it will inform THE BUYER in writing, with three (3) calendar
days prior to the respective deadline, and as soon as the contingency is
overcome, it shall announce the date for the resumption of
deliveries.”

     

    
      
         

      

      
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    THIRD
CLAUSE.  Include article 26 (PENALTY CLAUSE) to the Contract,
as follows:

    


    “26.
PENALTY
CLAUSE

    


    THE
BUYER, based on the provisions contained in Articles 867 and 949 of the Code of
Commerce, and during the term of the contract arising from acceptance of the
commercial offer, may enforce the penalty clause to THE SELLER in the event of
default of any of the obligations that the latter assumes, or due to imperfect
or inappropriate compliance equal to or greater than five percent (5%) of the
obligation to deliver in one calendar month, if THE BUYER deems as relevant and
necessary.

    


    In
accordance to the provisions of the preceding paragraph, in the event of a
failure attributable to THE SELLER, THE SELLER agrees to pay to THE BUYER, as a
penalty, a sum equivalent to three point zero percent (3.0%) of the amount
corresponding to the final schedule for the month in which the breach occurs, a
value that is calculated using the actual export price for that
month.

    


    The value
may be charged for each situation or act constituting infringement, and its
value will be compensated from the bill for the month following that one in
which it is notified by the Contract Administrator. THE SELLER expressly
authorizes THE BUYER to offset from the balances in their favor or any amounts
due by THE BUYER, the amount of the penalty clause.

    


    In order
for the offset to apply, the following procedure must be followed:

    


    (i) The
Contract Manager will notice THE BUYER of the events occurred.

    


    (ii)
Within the three (3) business days following receipt of notice, THE BUYER may
render explanations and indicate the reasons why it does not consider that the
infringement is attributable to THE BUYER.

    


     (iii)
The Contract Manager will analyze the explanations provided by THE SELLER and in
case of being acceptable, will proceed to notice said decision; on the contrary,
will notice that the compensation or offtake foreseen in this clause will apply
(the same will apply in case THE SELLER does not provide any
justification).

    


    If there
is no balance in favor of THE SELLER, THE BUYER may collect the amounts by means
of a legal proceeding for which the contract arising from acceptance of the
commercial offer, together with the communications through which the penalty
clause becomes effective, will be considered to have merit to enforce the action
(prestarán mérito de título
ejecutivo)

    


    To make
effective the penalty clause the report of the Contract Manager will be
enough.

    


    By
executing the penalty clause the rest of the obligations that have arisen in
virtue of the contract will not be considered to be extinct nor will exempt THE
SELLER from indemnifying any damages caused.”

    


    FORTH CLAUSE.  This
Amendment does not imply a novation to the contract arising from acceptance of
the commercial offer dated December 17, 2009 for the purchase of crude oil
produced in Chaza Block, which’s provisions remain intact except for what was
modified in this Amendment.

     

    
      
         

      

      
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    FIFTH CLAUSE. This Amendment
will be completed with the execution by the Parties. For the performance of the
dispositions within, the accreditation by THE SELLER of the payment of the
publication of this Amendment in the Public Contracts Newspaper (Diario Único de Contratación
Pública).

    


    SIXTH CLAUSE. Each of the
Parties acknowledges and accepts the taxes and/or deductions that apply in
accordance to the Law. The payment of all national, departmental and municipal
taxes, fees, charges, or similar that are caused or will be cause by this
Amendment, including but not limited to those incurred by the celebration,
formalization, implementation and termination or liquidation of this Amendment
or arising after the date of signature of this Amendment, shall be borne by the
taxpayer of the relevant tax, who must pay under the laws and
regulations.

    


    In
witness whereof, the Parties hereto have caused this Amendment to be duly
executed in Bogotá D.C. on the 8th day of November of 2010, in two copies of
equal value.

    


    
      	
              THE
      SELLER

            	 	
              THE
      BUYER

            
	
               

              /s/
      Julian Garcia Salcedo 

                
      

              JULIAN
      GARCIA SALCEDO

              Legal
      Representative

            	 	
               

              /s/
      Claudia L. Castellanos R.

              
                
      

              CLAUDIA
      L. CASTELLANOS R.

              Vice-president
      of Supply and Marketing

            


    

    


    
      
         

      

      
        6