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                                                                  EXHIBIT 10.12



                          PATINA OIL & GAS CORPORATION

                           RESTRICTED STOCK AGREEMENT

________________________________________________________________________________

               DATE OF GRANT:  March 16, 1998 (the "Grant Date:")


                              W I T N E S S E T H:

          1.  Grant of Restricted Stock. Patina Oil & Gas Corporation (the
              -------------------------                                   
"Company") on the above date has granted, and this Agreement evidences the grant
to Jay W. Decker ("Grantee"), subject to the terms and conditions which follow,
a total of 100,000 shares of Common Stock, par value $.01 per share ("Common
Stock"), of the Company. The restrictions against the transfer of the shares of
Common Stock granted to the Grantee shall lapse at the rate of 33.33% per year,
commencing on March 15, 1999 (the "Initial Lapsing Date").

          2.  Receipt and Delivery of Stock. (a) The Grantee waives receipt from
              -----------------------------                                     
the Company of a certificate or certificates representing the shares of Common
Stock granted hereunder, registered in the Grantee's names and bearing a legend,
in the form provided in Section 2(b) below. The Grantee acknowledges and agrees
that the Company shall retain custody of such certificate or certificates until
the restrictions on the transfer imposed by Section 3 on such shares lapse.
Concurrently with the execution of this Agreement, the Grantee has delivered to
the Company an irrevocable stock power endorsed in blank.

          (b) The Grantee acknowledges and agrees that each certificate for the
Common Stock granted hereunder shall bear the following legend:

          THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE
TRANSFERRED, SOLD OR OTHERWISE DISPOSED OF EXCEPT WHILE SUCH A REGISTRATION IS
IN EFFECT UNDER SUCH ACT AND APPLICABLE STATE SECURITIES LAWS OR PURSUANT TO AN
EXEMPTION FROM REGISTRATION UNDER SUCH ACT OR SUCH LAWS. THIS CERTIFICATE IS
ISSUED PURSUANT TO AND SUBJECT TO THE RESTRICTIONS ON TRANSFER AND OTHER
PROVISIONS OF RESTRICTED STOCK AGREEMENT DATED MARCH 16, 1998 BETWEEN THE
COMPANY AND THE GRANTEE REFERRED TO THEREIN A COPY OF WHICH IS ON FILE WITH THE
COMPANY. EXCEPT AS PROVIDED IN SUCH RESTRICTED STOCK AGREEMENT, THE SECURITIES
REPRESENTED BY THIS CERTIFICATE ARE NOT TRANSFERABLE AND ANY PURPORTED TRANSFER
IN VIOLATION OF THE 
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PROVISONS OF SUCH RESTRICTED STOCK AGREEMENT SHALL BE VOID AND OF NO FORCE AND
EFFECT.

          3.  Restrictions on Transfer of Stock. (a) The Grantee hereby
              ---------------------------------                        
acknowledges and agrees that the shares of Common Stock granted hereunder are
"restricted securities" under the Securities Act of 1933, as amended (the
"Securities Act"). The Grantee agrees not to, directly or indirectly, offer,
sell, transfer, assign or otherwise dispose of the beneficial ownership (any
such act, a "Transfer") of any such shares of Common Stock, except as permitted
hereunder and under the Securities Act and the rules and regulations thereunder
(including, without limitation, Transfers pursuant to Rule 144 under the
Securities Act).

          (b)   The restrictions on the Transfer of shares of Common Stock
granted hereunder shall lapse as follows: 

          (i)   on the Initial Lapsing Date, as to 33.33% of the Common Stock
                granted hereunder;

          (ii)  on the first anniversary of the Initial Lapsing Date, as to
                66.66% of the Common Stock granted hereunder;

          (iii) on the second anniversary of the Initial Lapsing Date, as to
                100% of the Common Stock granted hereunder; and

provided that, so long as the shares of Common Stock granted hereunder remain
pledged by the Grantee to the Company pursuant to that certain Pledge Agreement,
dated March 16, 1998, made by the Grantee to the Company, the Grantee will not
Transfer any share of Common Stock granted hereunder. Notwithstanding the
foregoing, the restrictions on Transfer shall lapse as to all of the Common
Stock granted hereunder in the event that the Grantee's employment is terminated
on account of death or "Disability" of Grantee (as defined in the Company's
Long-Term Disability plan) and upon the death or Disability of Grantee at any
time prior to the third anniversary of the Initial Lapsing Date, the forfeiture
provisions of paragraph 4. hereof shall not apply to any shares of Common Stock
granted to such Grantee which remain subject to the restrictions of paragraph
3(a).

          (c) The Grantee acknowledges and agrees that the shares of Common
Stock granted hereunder may be transferred only in one or more transactions
registered under the Securities Act (and, where applicable, the securities laws
of any state) or as to which an exemption from the registration requirements of
the Securities Act (and, where applicable, such laws) is available. As the
restrictions on Transfer imposed by this Section on shares of Common Stock
granted hereunder lapse, the shares of Common Stock as to which such
restrictions have lapsed shall be delivered to the Grantee without the
restrictive legend on the certificate for such shares.

     4.   Forfeiture of Stock. (a) In the event the Grantee's employment
          -------------------                                           
terminates (other than as a result of death or Disability) prior to the second
anniversary of the Initial Lapsing Date, 

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the Grantee's rights in the shares of Common Stock granted hereunder as to which
the restrictions in Section 3(a) have not lapsed shall be as follows (it being
understood that the Grantee shall not forfeit, following any termination of such
Grantee's employment with the Company, any shares of Common Stock granted
hereunder as to which the restrictions in Section 3 have lapsed):

          (i)  if such termination is by the Company without Cause (as defined
               below) or by the Grantee for Good Reason (as defined below), the
               Grantee shall be entitled to a pro rata portion of the shares of
               Common Stock scheduled to vest on the next succeeding anniversary
               of the Initial Vesting Date (based on the number of days such
               Grantee continues to be employed during the relevant one-year
               period prior to such anniversary date), and all remaining shares
               of Common Stock granted hereunder as to which the restrictions in
               Section 3 have not lapsed will be forfeited;

          (ii) if such termination is by the Company for Cause or by the Grantee
               without Good Reason, all shares of Common Stock granted hereunder
               as to which the restrictions in Section 3 have not lapsed will be
               forfeited;

          (b)  The Compensation Committee of the Company's Board of Directors or
its agent shall act promptly to record forfeitures pursuant to this Section on
the stock transfer books of the Company.


          (c)  As used herein, the following terms shall have the following
meanings:

          (i)  "Cause" shall mean (A) an act or acts of dishonesty by the
               Grantee constituting a felony under applicable law and/or (B) any
               act resulting or intending to result directly or indirectly in
               gain to or personal enrichment of the Grantee at the Company's
               expense. Notwithstanding the foregoing, the Grantee shall not be
               deemed to have been terminated for Cause unless and until there
               shall have been delivered to the Grantee a copy of a resolution
               duly adopted by the affirmative vote of not less than a majority
               of the Compensation Committee of the Board called and held for
               the purpose (after reasonable notice and opportunity for the
               Grantee, together with counsel, to be heard before the
               Compensation Committee of the Board), finding that in the good
               faith opinion of the Compensation Committee of the Board the
               Grantee engaged in the conduct described above.

          (ii) "Good Reason" shall mean, without Grantee's written consent, (A)
               a change in status, position or responsibilities which, in the
               Grantee's reasonable judgment, does not represent a promotion
               from existing status, position or responsibilities as in effect
               on the date of this Agreement (the "Effective Date") or the
               assignment of any duties or responsibilities which, in the
               Grantee's reasonable judgment, are inconsistent with such status,
               position or responsibilities or any removal from or failure to
               reappoint or reelect the Grantee to any of such positions, except
               in connection with the 

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               termination for total and permanent disability, death or cause or
               by him other than for Good Reason; (B) a reduction by the Company
               in the Grantee's base salary as in effect on the Effective Date;
               (C) the relocation of the Grantee by the Company to any place not
               within 25 miles of the location at which the Grantee performed
               duties on the Effective Date, except for required travel on the
               Company's business to an extent substantially consistent with
               business travel obligations on the Effective Date; (D) the
               failure of the Company to continue in effect any incentive, bonus
               or other compensation plan in which the Grantee participates,
               including but not limited to the Company's stock option and
               deferred compensation plans, unless an equitable arrangement
               (embodied in an ongoing substitute or alternative plan),
               evidenced by the Grantee's written consent, has been made with
               respect to such plan, or the failure by the Company to continue
               the Grantee's participation therein, or any action by the Company
               which would directly or indirectly materially reduce
               participation therein; (E) the failure by the Company to continue
               to provide the Grantee with benefits substantially similar to
               those enjoyed or entitled under any of the Company's pension,
               profit sharing, life insurance, medical, dental, health and
               accident, or disability plans at the Effective Date, the taking
               of any action by the Company which would directly or indirectly
               materially reduce any of such benefits or deprive the Grantee of
               any material fringe benefit enjoyed or entitled to at the
               Effective Date, or the failure by the Company to provide the
               number of paid vacation and sick leave days to which the Grantee
               is entitled on the basis of years of service with the Company in
               accordance with the Company's normal vacation policy in effect on
               the Effective Date; or (F) any request by the Company that the
               Grantee participate in an unlawful act or take any action
               constituting a breach of the Grantee's professional standard of
               conduct.

          5.        Dividends; Voting. If the Grantee is a shareholder of record
                    -----------------
on any applicable record date, the Grantee shall receive any dividends on the
Common Stock granted hereunder when paid regardless of whether the restrictions
imposed by Section 3 hereof have lapsed. If the Grantee is a shareholder of
record on any applicable record date, the Grantee shall have the right to vote
the Common Stock granted hereunder regardless of whether the restrictions
imposed by Section 3 hereof have lapsed.

          6.        No Right to Employment. The execution and delivery of this
                    ----------------------
Agreement and the granting of Common Stock hereunder shall not constitute or be
evidence of any agreement or understanding, either express or implied, on the
part of the Company or its subsidiaries to employ the Grantee for any specific
period or in any particular capacity and shall not prevent the Company or its
subsidiaries from terminating the Grantee's employment at any time with or
without cause.

          7.        Registration. The registration of the Common Stock granted
                    ------------                                              
hereunder shall be governed by the Stock Purchase Agreement, dated March 16,
1998 (the "Stock 

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Purchase Agreement"), between the Company and the Grantee. Except as provided in
the Stock Purchase Agreement, the Grantee acknowledges that the Grantee has no
right to require the Company to register the shares of Common Stock granted
hereunder.
 
          8.   Change in Control. In the event of a Change in Control (as
               -----------------                                         
defined in the Company's Change in Control Plan (the "Change in Control Plan"),
vesting of the Common Stock granted hereunder shall be in accordance with the
Company's Change in Control Plan.
 
          9.   Application of Laws. The granting of Common Stock hereunder shall
               -------------------                                              
be subject to all applicable laws, rules and regulations and to such approvals
of any governmental agencies as may be required.

          10.  Taxes. Any taxes required by federal, state of local laws to be
               -----                                                          
withheld by the Company on the delivery of Common Stock hereunder shall be paid
to the Company by the Grantee by the time such taxes are required to be paid or
deposited by the Company. Prior to the lapse of restrictions, the Grantee shall
be given the option to satisfy any tax obligations by (i) tendering cash to the
Company prior to the time of delivery or (ii) authorizing the conversion to cash
by the Company of a sufficient amount of Common Stock prior to delivery.

          11.  Notices. Any notices required to be given hereunder to the
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Company shall be addressed to Patina Oil & Gas Corporation, 1625 Broadway, Suite
2000, Denver, Colorado 80202 (Phone (303) 389-3600; Fax (303) 595-7408)
Attention:  General Counsel, and any notice required to be given hereunder to
the Grantee shall be sent to the Grantee's address as shown of the records of
the Company.

          IN WITNESS WHEREOF, the Company, by its duly authorized officer, and
the Grantee have executed this agreement as amended and restated in duplicate as
of the Grant Date first above written.

                                       PATINA OIL & GAS CORPORATION



                                       By:     /s/ Brian J. Cree             
                                               ------------------------------
                                               Brian J. Cree                 
                                               Executive Vice President,     
                                               Chief Operating Officer        

                                       GRANTEE


                                               /s/ Jay W. Decker             
                                               ------------------------------
                                                                             
                                       By:     Jay W. Decker                  

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