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                                                                    EXHIBIT 10.c

                       AMENDMENT TO OPERATING AGREEMENTS

           In consideration of the premises, and the agreements set forth
herein, GHK COMPANY COLOMBIA, SOCIEDAD INTERNACIONAL PETROLERA S.A., CIMARRONA,
L.L.C., SEVEN SEAS PETROLEUM COLOMBIA, INC. and PETROLINSON, S.A. hereby agree
to amend the Rio Seco and Dindal Operating Agreements as follows:

           1. The following language shall be added at the end of Article 1.13:

              "In addition, the area and depth covered by the "On-Top
              Contract," defined in that certain Exploration Agreement
              between the Parties dated January 25, 2001, shall be a part
              of the Contract Area hereunder,"

           2. The language in Article 1.4 which reads,

                           "plus four (4) percentage points..."

                  shall be amended to read,

                           "plus eight (8) percentage points..."

           3. The language in Article 3.2(D) which reads,

                           "Each Party shall pay when due, in accordance with
                           the Accounting Procedure, its Participating Interest
                           share of Joint Account expenses, including cash
                           advances and interest, accrued pursuant to this
                           Agreement."

                  shall be amended to read,

                           "Each Party shall pay when due, in accordance with
                           the Accounting Procedure, its Participating Interest
                           share of Joint Account expenses made in connection
                           with approved Work Programs and Budgets and
                           otherwise when Operator commits or expends funds for
                           the Joint Account or Exclusive Operations in
                           accordance with explicit authority granted to the
                           Operator under the terms of this Agreement,
                           including cash advances and interest, accrued
                           pursuant to this Agreement."


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           4. The language in Article 4.2(A) which reads,

                           "Subject to the terms and conditions of this
                           Agreement, Operator shall have all of the rights,
                           functions and duties of Operator under the Contract,
                           and shall have exclusive charge of and shall conduct
                           all Joint Operations."

                  shall be amended to read,

                           "Subject to the terms and conditions of this
                           Agreement, Operator shall have all of the rights,
                           functions and duties of Operator under the Contract,
                           and shall have exclusive charge of and shall conduct
                           all Joint Operations in accordance with this
                           Agreement and the instructions of the Operating
                           Committee."

           5. The language in Article 4.2(B)(10) which reads,

                           "Have in accordance with the decisions of the
                           Operating Committee, the exclusive right and
                           obligation to represent the Parties in all dealings
                           with the Government with respect to matters arising
                           under the Contract and Joint Operations."

                  shall be amended to read,

                           "Have in accordance with the decisions and
                           directions of the Operating Committee, the exclusive
                           right and obligation to represent the Parties in all
                           dealings with the Government with respect to matters
                           arising under the Contract and Joint Operations."

           6. The language in Article 4.2(B)(10) which reads,

                           "Nothing contained in this Agreement shall restrict
                           any Party from holding discussions with the
                           Government with respect to any issue peculiar to its
                           particular business interests arising under this
                           Agreement, but in such event such Party shall
                           promptly advise the Parties, if possible, before and
                           in any event promptly after such discussions,
                           provided that such Party shall not be required..."

                  shall be amended to read,

                           "Nothing contained in this Agreement shall restrict
                           any Party from holding discussions or from
                           communicating by letter or otherwise with the
                           Government with respect to any issue peculiar to its
                           particular business interests arising under this
                           Agreement, provided that Non-Operators shall


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                           advise the other Parties, in writing, not less than
                           two (2) business days prior to such discussions or
                           transmitting such communication, provided that no
                           Party shall be required ..."

           7. The language in Article 4.10(A) and (A) (1) which reads,

                           "Subject to Article 4.11, Operator shall be removed
                           upon receipt of notice from any Non-Operator if:


                           (A) An order is made by a court or an effective
                           resolution is passed for the dissolution,
                           liquidation, winding up, or reorganization of
                           Operator;"

                  shall be amended to read,

                           "Except as otherwise expressly set forth below and
                           notwithstanding Article 4.11, Operator shall be
                           automatically and immediately removed upon the
                           occurrence of any of the following events and
                           Sipetrol shall immediately be named Operator:

                           (A) An order is made by a court or an effective
                           resolution is passed for the dissolution,
                           liquidation, winding up, or reorganization of
                           Operator (or, in the case of the current Operator,
                           GHK, for the dissolution, liquidation, or winding up
                           of Seven Seas Petroleum Inc. ("Seven Seas") or any
                           company which is directly or indirectly owned by
                           Seven Seas and which directly or indirectly owns the
                           stock of (i) Operator or (ii) any other company that
                           is a Party to this Agreement), in any jurisdiction;"

           8. The language in Article 4.10(A)(2) which reads,

                           "Operator dissolves, liquidates or terminates its
                           corporate existence;"

                  shall be amended to read,

                           "Operator dissolves, liquidates or terminates its
                           corporate existence (or, subject to the provisions
                           of Article 4.10(E), in the case of the current
                           Operator, GHK, if Seven Seas dissolves, liquidates
                           or terminates its corporate existence other than in
                           connection with a change of control or a sale of
                           substantially all of its assets);"


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           9. The language in Article 4.10(A)(3) which reads,

                           "Operator becomes insolvent, bankrupt or makes an
                           assignment for the benefit of creditors; or"

                  shall be amended to read,

                           "Operator (or, subject to the provisions of Article
                           4.10(E), in the case of the current Operator, GHK,
                           if Seven Seas or any company which is directly or
                           indirectly owned by Seven Seas and which directly or
                           indirectly owns the stock of (i) Operator or (ii)
                           any other company that is a Party to this Agreement)
                           becomes insolvent, bankrupt or makes an assignment
                           for the benefit of creditors, in any jurisdiction;
                           or"

           10. The language in Article 4.10(A)(4) which reads,

                           "A receiver is appointed for a substantial part of
                           Operator's Assets."

                  shall be amended to read,

                           "A receiver is appointed for a substantial part of
                           Operator's (or, in the case of the current Operator,
                           GHK, of Seven Seas') Assets."

           11. There shall be added a new Article 4.10(A)(5) to read,

                           "In the case of the current Operator, GHK, if any of
                           the following events occurs in relation to GHK or
                           Seven Seas or any company which is directly or
                           indirectly owned by Seven Seas and which directly or
                           indirectly owns the stock of Operator or) any other
                           company that is a Party to this Agreement): (i) an
                           `Event of Default' (as defined in that certain
                           Indenture dated as of May 7, 1998, between Seven
                           Seas and The Bank of Nova Scotia Trust Company of
                           New York, as trustee pertaining to $110,000,000 12
                           1/2% Senior Notes due 2005 (the "Indenture")) occurs
                           under the Indenture, or (ii) if there occurs an
                           event of default under the Stillwater Bank Loan
                           Agreement between Seven Seas and The Stillwater
                           National Bank, N.A., dated December 20, 2000, or
                           (iii) if there occurs a default under any other
                           material agreement pertaining to any existing or
                           future bank loans, other loans for borrowed money,
                           debt securities convertible into equity securities,
                           or preferred stock arrangements such companies may
                           enter into that


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                           call for the repayment of principal, and the
                           defaults or events of default described in
                           the preceding clauses (i), (ii) and (iii) have not
                           been timely cured or waived within 30 days from the
                           date of the default. In the event of any such
                           default(s) under the above mentioned documents and
                           such default(s) is publicly disclosed, GHK shall
                           send all Parties, within twenty-four (24) hours of
                           the release all publicly disclosed information
                           relating to such default(s). If Seven Seas is a
                           privately held company or such notice of default is
                           sent to a privately held Affiliate of Seven Seas,
                           then GHK shall send a copy of such default notice to
                           all Parties within five days of its issuance.


                           In the event that Seven Seas or any of its
                           Affiliates, enters into any future bank loans, debt,
                           convertible debt, or preferred stock arrangements or
                           any other arrangement that calls for the repayment
                           of principal, then GHK shall make available to all
                           non-Operators a copy of said instruments within
                           twenty-four (24) hours of its public disclosure upon
                           request. If Seven Seas and its Affiliates are all
                           privately held entities, then GHK shall make said
                           instruments available upon request.


                           In addition, GHK shall send any letters related to
                           any such defaults from any lender, debt holder,
                           trustee, or any party representing them within three
                           (3) days of Seven Seas' receipt of same.

           12. There shall be added a new Article 4.10(A)(6) to read,

                           "For the purposes of Article 4.10(A), the term
                           `directly or indirectly owned' shall be applicable
                           if fifty percent (50%) or more of the stock, debt or
                           assets of the owned party is owned by the owning
                           party."

           13. There shall be added a new Article 4.10(E) to read,

                           "The parenthetical language in Articles 4.10(A)(2)
                           and 4.10(A)(3) shall not apply if there is a direct
                           or indirect change of control of Seven Seas to a
                           non-Affiliate of Seven Seas which the Parties agree
                           is solvent, which agreement shall not be
                           unreasonably withheld."


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           14. The language in Article 6.7(B) which reads,

                           "at such time that Operator is certain that the
                           limits of Article 6.7(A) will be exceeded, Operator
                           shall furnish a supplemental AFE for the estimated
                           overexpenditures...."

                  shall be amended to read,

                           "at such time that Operator reasonably believes that
                           the limits of Article 6.7(A) will be exceeded,
                           Operator shall furnish a supplemental AFE for the
                           estimated overexpenditures...."

           15. The language in Article 8.1 which reads,

                           "Any Party that fails to pay when due its
                           Participating Interest share of Joint Account
                           expenses including cash advances and interest,
                           accrued pursuant to this Agreement (a `Defaulting
                           Party'), shall be in default under this Agreement."

                  shall be amended to read,

                           "Any Party that fails to pay when due its
                           Participating Interest share of Joint Account
                           expenses made in connection with approved Work
                           Programs and Budgets, and otherwise when Operator
                           commits or expends funds for the Joint Account or
                           Exclusive Operations, in accordance with explicit
                           authority granted to the Operator under the terms of
                           this Agreement, including cash advances and
                           interest, accrued pursuant to this Agreement (a
                           `Defaulting Party'), shall be in default under this
                           Agreement."

           16. Each Operating Agreement shall be reprinted and re-executed by
all parties hereto. The Title of each such document shall be "First Amended and
Restated International Operating Agreement" with appropriate changes made
therein to reflect this fact; to refer only to existing parties; and to
otherwise reflect these amendments.

           Except as specifically amended hereby, the Rio Seco and Dindal
Operating Agreements shall remain in effect as previously written.


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         EXECUTED by the Parties this 25th day of January, 2001, effective for
all purposes as of such date.

FARMORS                                     FARMEES

SOCIEDAD INTERNACIONAL PETROLERA S.A.       GHK COMPANY COLOMBIA

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Authorized Agent                            Authorized Agent



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Print or Type Name                          Print or Type Name



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Title                                       Title


January 25, 2001                            January  25, 2001


CIMARRONA L.L.C. BY MTV                     SEVEN SEAS PETROLEUM COLOMBIA, INC.
INVESTMENTS LIMITED PARTNERSHIP,
SOLE MEMBER BY MTV ASSOCIATES, INC.,
MANAGING GENERAL PARTNER P. MARK
MOORE, PRESIDENT                            ----------------------------------
                                            Authorized Agent



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Authorized Agent                            Print or Type Name



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Print or Type Name                          Title



------------------------------------        January 25, 2001
Title

January 25, 2001                            PETROLINSON S. A.

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                                            Authorized Agent


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                                            Print or Type Name


                                            ----------------------------------
                                            Title

                                            January 25, 2001


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