SEAGULL ENERGY CORPORATION
                     EXECUTIVE SUPPLEMENTAL RETIREMENT PLAN

                              MEMBERSHIP AGREEMENT

         WHEREAS, JAMES T. HACKETT ("Employee") has been selected as eligible to
become a Member of the SEAGULL ENERGY CORPORATION EXECUTIVE SUPPLEMENT
RETIREMENT PLAN (the "Plan"); and

         WHEREAS,  the Plan provides that each Member shall execute a Membership
Agreement setting forth the terms and conditions of his membership; and

         WHEREAS,  Employee  desires to become a Member of the Plan on the terms
and  conditions  set forth  therein,  in the  Employment  Agreement  between the
Company and Employee (the "Employment Agreement"), and in this Agreement;

         NOW, THEREFORE, the parties hereto agree as follows:

         1.  Employee  agrees to become a Member  of the Plan,  effective  as of
September 16, 1998.

         2. For purposes of Section 1.01(5) of the Plan,  Employee's  considered
period shall be his last  thirty-six  consecutive  months of  employment  or, if
less, all of his completed months of employment.

         3. For purposes of Section 1.01(8) of the Plan, Employee's Compensation
shall include (a) "deemed  salary" equal to the base salary that Employee  would
have  received if he had not received an option to purchase  common stock of the
Company in lieu of such  salary  pursuant  to  paragraph  3.1 of the  Employment
Agreement and (b) Employee's  annual bonus under the Seagull Energy  Corporation
Executive Incentive Plan (or any successor thereto).

         4. Employee's Applicable Percentage under the Plan shall be 50%.

         5.  Employee's  Vested  Interest in his benefit under the Plan shall be
determined in accordance with the following Vesting Schedule:

<TABLE>
<S>                                                              <C>
                                                                 Vested Interest

         Prior to September 16, 1999                                   50%
         As of September 16, 1999*                                     60%
         As of September 16, 2000*                                     70%
         As of September 16, 2001*                                     80%
         As of September 16, 2002*                                     90%
         As of September 16, 2003*                                    100%
</TABLE>

         *provided  that  Employee  is  employed by Company on such date and has
         been  so  employed  by  Company  on  a  full-time   basis   during  the
         twelve-month period immediately preceding such date.

                                       -1-


<PAGE>


Notwithstanding  the foregoing,  Employee's Vested Interest in his benefit under
the Plan shall be 100% in the event of his Involuntary Termination (as such term
is defined in the  Severance  Agreement  between the Company and  Employee  (the
"Severance  Agreement"))  within two years after the date upon which a Change of
Control (as such term is defined in the Severance Agreement) occurs.

         6. Section 5.02 of the Plan shall not apply with respect to Employee.

         EXECUTED this 4th day of November, 1998.

                                            SEAGULL ENERGY CORPORATION

                                            By:    /s/ William L. Transier
                                            Name:  William L. Transier
                                            Title: Executive Vice President and
                                                   Chief Financial Officer

                                                    EMPLOYEE

                                            /s/ James T. Hackett
                                            James T. Hackett    
VEHOU02:121810.1

                                       -2-