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                              RESIGNATION AGREEMENT

          This Resignation Agreement (this "Agreement") by and between Nuevo
Energy Company, a Delaware corporation (the "Company"), and Michael P. Darden
(the "Executive"), is dated as of January 11, 2002 (the "Execution Date").

          WHEREAS, the Executive has been employed by the Company as its Vice
President, Business Development; and

          WHEREAS, the Company and the Executive have agreed that it is in the
best interest of the Company and the Executive for the Executive to resign, and
they wish to set forth their mutual agreement as to the terms and conditions of
such resignation;

          NOW, THEREFORE, the Company and the Executive hereby agree as follows:

          1. Resignation. Unless this Agreement is revoked pursuant to Section
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8, effective as of January 21, 2002 or such other date after the Execution Date
specified by the Company in writing to Executive, (the "Resignation Date"), the
Executive shall be deemed to have voluntarily resigned from his employment with
the Company, and from all other positions the Executive then held as an officer
or employee of any of the Company's subsidiaries or affiliates (the Company and
all of its subsidiaries and affiliates are hereinafter referred to as the
"Affiliated Entities").

          2. Severance Payments and Benefits. (a) Within seven days of the
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Revocation Date, (as defined in Section 8(b)), the Company shall pay to the
Executive a lump sum in cash of the amounts set forth on Exhibit A hereto.

               (b) For twelve months following the Resignation Date, the Company
shall continue to provide the Executive and his eligible dependents with medical
insurance benefits (but not life or disability insurance) on the same terms and
conditions as employees of the Company, as in effect from time to time, as if he
had remained employed during that period, subject to his payment of such
employee contributions, copayments and similar charges as apply to employees
generally; provided, that such continued benefits shall terminate to the extent
the Executive becomes eligible for the same type of benefits (i.e., medical,
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dental and/or health insurance benefits) from another employer. The period for
the required continuation coverage under Section 601 et seq. of the Employee
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Retirement Income Security Act of 1974, as amended, and Section 4980B of the
Internal Revenue Code of 1986, as amended (the "Code") (known as "COBRA"
benefits), shall be considered to begin on the Resignation Date.

               (c) Within ninety days after the Revocation Date the Company
shall pay to the Executive a lump sum in cash as determined in accordance with
the Company's Deferred Compensation Plan of which the most current balance is
set forth on Exhibit A hereto, which, together with any amounts contributed to
the Plan from the date of the balance to the Executive's resignation, represents
(solely for explanation and not in limitation or expansion of the obligation to
pay such amount) the amount to which the Executive is entitled under the
Company's Deferred Compensation Plan, which payment shall be in satisfaction of
any of the Executive's rights under the Company's Deferred Compensation Plan.
The value of the non-cash investments shall be established as of the Resignation
Date. In addition, the Executive shall
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be entitled to receive his vested benefits under the Company 401(k) Plan, in
accordance with the terms thereof.

               (d) The Company shall reimburse the Executive for any
unreimbursed business expenses incurred by the Executive on or prior to the
Resignation Date pursuant to the Company's reimbursement policies, within thirty
days following the Executive's presentation of an invoice to the Company;
provided, that the Company shall not reimburse the Executive for any expenses
for which the invoice is received by the Company after April 30, 2002.

          3. Equity and Performance Awards. Exhibit A hereto sets forth a
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complete list of all of the Executive's currently outstanding stock options (the
"Stock Options") under the 1990 Stock Option Plan, the 1993 Stock Incentive Plan
and the 1999 Stock Incentive Plan. Notwithstanding any provision contained in
the applicable agreement governing any Stock Option (an "Award Agreement") or in
the applicable plan, the Stock Options shall be treated as set forth in this
Section 3, and the applicable Award Agreements are hereby amended to the extent
necessary to implement this Section 3. All Stock Options set forth in Exhibit A
as being retained by the Executive shall be exercisable in accordance with the
grant agreement for 365 days following the Resignation Date (or, if earlier,
until the end of their scheduled term), and shall then expire to the extent not
previously exercised. All Stock Options set forth in Exhibit A as being
surrendered by the Executive shall be cancelled as of the Revocation Date and
the Executive shall have no further right or interest in such cancelled options.

          4. Mutual Nondisparagement. (a) The Executive shall not make,
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participate in the making of, or encourage or facilitate any other person to
make, any statements, written or oral, which criticize, disparage, or defame the
goodwill or reputation of, or which are intended to embarrass or adversely
affect the morale of, any of the Affiliated Entities or any of their respective
present, former or future directors, officers, executives, employees and/or
shareholders. The Executive further agrees not to make any negative statements,
written or oral, relating to his employment, the termination of his employment,
or any aspect of the business of the Affiliated Entities.

               (b) The Company shall advise its executive officers and directors
not to make and will make a reasonable effort to prevent its executive officers
and directors from making any negative statements, written or oral, relating to
the Executive's employment or the termination of his employment or statements
which are intended to embarrass the Executive.

               (c) Notwithstanding the foregoing, nothing in this Section 4
shall prohibit any person from making truthful statements when required by order
of a court or other body having jurisdiction, or as otherwise may be required by
law or legal process.

          5. Mutual Confidentiality. The existence of and terms and conditions
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of this Agreement shall be held confidential by the parties hereto, except for
disclosure (a) by the Company as may be required by applicable securities laws,
as determined by the Company upon the advice of outside counsel, (b) by the
Executive to his legal and financial advisors and his spouse, each of whom shall
be instructed by the Executive to maintain the terms of this Agreement in strict
confidence in accordance with the terms hereof, (c) by either party if required
by order of a court or other body having jurisdiction over such matter, and (d)
by either party with the written consent of the other. With respect to
disclosures under (a) or (c) the disclosing party shall give the other prior
notice where reasonably practical and shall provide an

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opportunity to comment on the disclosure. In addition, the Executive shall hold
in a fiduciary capacity for the benefit of the Company all secret or
confidential information, knowledge or data relating to the Affiliated Entities
and their respective businesses that he has obtained that is not or does not
become public knowledge (other than as a result of the Executive's violation of
this Section 5) ("Confidential Information"). The Executive shall not
communicate, divulge or disseminate Confidential Information at any time, except
with the prior written consent of the Company or as otherwise required by law or
legal process.

          6. Cooperation. For other than matters that present a potential
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conflict of interest, the Executive shall make himself reasonably available to
the Company following the Resignation Date to assist the Affiliated Entities, as
may be requested by the Company at mutually convenient times and places, with
respect to pending and future litigations, arbitrations, governmental
investigations or other dispute resolutions relating to or in connection with
matters that arose during the Executive's employment with the Company. The
Company will compensate the Executive for providing assistance under this
Section 6 at the higher of either $100 per hour or the Executive's then current
billing rate if the Executive is then in the private practice of law . The
Company will reimburse the Executive for all reasonable expenses and costs he
may incur as a result of providing such assistance, upon receipt of proper
documentation thereof.

          7. Remedies. The Executive acknowledges and agrees that because of the
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nature of the business in which the Company and the other Affiliated Entities
are engaged and because of the nature of the Confidential Information to which
the Executive has had access during his employment, it would be impractical and
excessively difficult to determine the actual damages of the Company and the
other Affiliated Entities in the event the Executive breached any of the
covenants of Sections 4 or 5, and remedies at law (such as monetary damages) for
any breach of the Executive's covenants under Sections 4 or 5 would be
inadequate. The Company acknowledges and agrees that it would be impractical and
excessively difficult to determine the actual damages of the Executive in the
event the Company breached any of the covenants of Sections 4 and 5, and
remedies at law (such as monetary damages) for any breach of the Company's
covenants under Sections 4 and 5 would be inadequate. The parties therefore
agree and consent that if either of them commits any such breach or threatens to
commit any such breach, the other party shall have the right (in addition to,
and not in lieu of, any other right or remedy that may be available to it) to
temporary and permanent injunctive relief from a court of competent
jurisdiction, without posting any bond or other security and without the
necessity of proof of actual damage. With respect to any provision of Sections 4
or 5 that is finally determined to be unenforceable, the Executive and the
Company hereby agree that this Agreement or any provision hereof may be reformed
so that it is enforceable to the maximum extent permitted by law. If any of the
covenants of Sections 4 or 5 is determined to be wholly or partially
unenforceable in any jurisdiction, such determination shall not be a bar to or
in any way diminish the Company's right to enforce any such covenant in any
other jurisdiction.

          8. Release. (a) In consideration of the payments and benefits set
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forth in this Agreement, except for the rights expressly provided herein, the
Executive for himself, his heirs, administrators, representatives, executors,
successors and assigns (collectively "Releasors") does hereby irrevocably and
unconditionally release, acquit and forever discharge the Company and its
subsidiaries, shareholders, affiliates, divisions, trustees, officers,
directors, partners, agents, and former and current employees, including without
limitation all persons acting by, through,

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under or in concert with any of them (collectively, "Releasees"), and each of
them from any and all charges, complaints, claims, liabilities, obligations,
promises, agreements, including the Severance Protection Agreement entered into
between the parties on March 25, 2001, which is hereby cancelled and terminated
for all purposes, controversies, damages, remedies, actions, causes of action,
suits, rights, demands, costs, losses, debts and expenses (including attorneys'
fees and costs) of any nature whatsoever, known or unknown, whether in law or
equity and whether arising under federal, state or local law and in particular
including any claim for discrimination based upon race, color, ethnicity, sex,
age (including the Age Discrimination in Employment Act), national origin,
religion, disability, or any other unlawful criterion or circumstance, which the
Executive and Releasors had, now have, or may have in the future against each or
any of the Releasees from the beginning of the world until the Execution Date
relating to the Executive's employment with the Company and its subsidiaries and
affiliates. In consideration of the payments and benefits set forth in this
Agreement, except for the rights expressly provided herein, the Company, on
behalf of itself and the Releasees, hereby irrevocably and unconditionally
releases, acquits and forever discharges the Executive from any and all charges,
complaints, claims, liabilities, obligations, promises, agreements
controversies, damages, remedies, actions, causes of action, suits, rights,
demands, costs, losses, debts and expenses (including attorneys' fees and costs)
of any nature whatsoever, known or unknown, whether in law or equity and whether
arising under federal, state or local law which the Company had, now has, or may
have in the future against Executive from the beginning of the world until the
Execution Date relating to the Executive's employment with the Company and its
subsidiaries and affiliates but excluding only those acts which are unknown to
the Company as of the date hereof that would constitute a basis for termination
for cause as defined under the Executive's Employment Agreement.

               (b) The Executive acknowledges that: (i) this entire Agreement is
written in a manner calculated to be understood by him; (ii) he has been advised
to consult with an attorney before executing this Agreement; (iii) he was given
a period of twenty-one days within which to consider this Agreement; and (iv) to
the extent he executes this Agreement before the expiration of the
twenty-one-day period, he does so knowingly and voluntarily and only after
consulting his attorney. The Executive shall have the right to cancel and revoke
this Agreement on or before January 21,2002, and this Agreement shall not become
effective, and no money shall be paid hereunder, until after January 21, 2002
(the "Revocation Date"). In order to revoke this Agreement, the Executive shall
deliver to the Company, prior to the Revocation Date, a written notice of
revocation. Upon such revocation, this Agreement shall be null and void and of
no further force or effect.

          9. Return of Property. (a) Within 15 days after the Resignation Date,
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the Executive shall surrender to the Company all property of the Affiliated
Entities in the Executive's possession and all property made available to the
Executive in connection with his employment by the Company, including, without
limitation, any and all records, manuals, customer lists, notebooks, computers,
computer programs, cellular phones, and files, papers, electronically stored
information and documents kept or made by the Executive in connection with the
Executive's employment.

               (b) For 45 days after the Resignation Date, the Company shall
provide the Executive with off-site voicemail services, and during such period,
the Executive's former

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secretary shall be permitted to forward voicemail and electronic mail from the
Company's voicemail and electronic mail systems to the Executive's off-site
voicemail and personal electronic mail account.

          10. Entire Agreement; Other Benefits. This Agreement sets forth the
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entire agreement of the Company and the Executive with respect to the subject
matter hereof, and supersedes in its entirety the Employment Agreement, between
the Company and the Executive, dated as of May 11, 1998, under which neither
party shall have any further obligation or liability to the other, and, except
as otherwise set forth in this Agreement with respect to the option grants,
deferred compensation plan, and medical benefits or the Executive's rights to
the vested component of his 401(K) account, any severance plan, policy or
arrangement of any of the Affiliated Entities, including without limitation the
Executive's Severance Protection Agreement with the Company dated as of March
25, 2001. Without limiting the generality of the foregoing, the Executive
expressly acknowledges and agrees that except as specifically set forth in this
Agreement, he is not entitled to receive any severance pay, severance benefits,
compensation or employee benefits of any kind whatsoever from any of the
Affiliated Entities.

          11. Successors. This Agreement is personal to the Executive and
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without the prior written consent of the Company shall not be assignable by the
Executive other than by will or the laws of descent and distribution. This
Agreement shall inure to the benefit of and be enforceable by the Executive's
legal representatives. This Agreement shall inure to the benefit of and be
binding upon the Company and its successors and no assignment shall release the
Executive or the Company or its successors from any obligations herein.

          12. Amendment. This Agreement may be amended, modified or changed only
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by a written instrument executed by the Executive and the Company.

          13. Governing Law; Consent to Suit. (a) This Agreement shall be
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governed by and construed in accordance with the laws of the State of Texas,
without reference to principles of conflict of laws. The captions of this
Agreement are not part of the provisions hereof and shall have no force or
effect.

               (b) The parties hereto irrevocably consent to jurisdiction in the
courts of the state of Texas for resolution of any claim or dispute arising
hereunder, and such shall be the exclusive forum for the resolution of such
claim or dispute.

          15. Notices. All notices and other communications hereunder shall be
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in writing; shall be delivered by hand delivery to the other party or mailed by
registered or certified mail, return receipt requested, postage prepaid; shall
be deemed delivered upon actual receipt; and shall be addressed as follows:

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                                    If to the Executive:

                                    Michael P. Darden
                                    17231 Blackhawk #707
                                    Friendswood, Texas 77546

                                    If to the Company:

                                    Nuevo Energy Company
                                    1331 Lamar
                                    Suite 1650
                                    Houston, Texas 77010

                                         Attention: Bruce K. Murchison

or to such other address as either party shall have furnished to the other in
writing in accordance herewith.

          16. Tax Withholding. Notwithstanding any other provision of this
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Agreement, the Company may withhold from any amounts payable under this
Agreement, or any other benefits received pursuant hereto, such minimum Federal,
state and/or local taxes as shall be required to be withheld under any
applicable law or regulation.

          IN WITNESS WHEREOF, each of the parties hereto has duly executed this
Agreement as of the date first set forth above.

                                    /S/ Michael P. Darden
                                    --------------------------------
                                    Michael P. Darden


                                    NUEVO ENERGY COMPANY


                                    By: /S/ James Payne
                                        ------------------------------
                                        James Payne
                                        Chief Executive Officer

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                                    EXHIBIT A

Severance Compensation