<PAGE>

                            AMENDMENT #1 TO FORM 10-Q



                                    FORM 10-Q


                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549


    [ X ]         QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF
                              THE SECURITIES EXCHANGE ACT OF 1934

                  For the quarterly period ended June 30, 1997

                                       OR

    [   ]         TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF
                              THE SECURITIES EXCHANGE ACT OF 1934

         For the transition period from ____________ to_______________

                         Commission File number 0-17023


                    SWIFT ENERGY INCOME PARTNERS 1986-D, LTD.
             (Exact name of registrant as specified in its charter)

<TABLE>
<S>                                           <C>       
                  Texas                                    76-0208087
(State or other jurisdiction of organization) (I.R.S. Employer Identification No.)
</TABLE>


                        16825 Northchase Drive, Suite 400
                              Houston, Texas 77060
                    (Address of principal executive offices)
                                   (Zip Code)

                                  (281)874-2700
              (Registrant's telephone number, including area code)

                                      None
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the  preceding 12 months (or for such  shorter  period that the  Registrant  was
required  to file  such  reports),  and  (2) has  been  subject  to such  filing
requirements for the past 90 days.

Yes  X      No
    ---        ---



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                                   SIGNATURES



Pursuant to the  requirements of Section 13 or 15(d) of the Securities  Exchange
Act of 1934,  the  Registrant  has duly  caused  this report to be signed on its
behalf by the undersigned thereunto duly authorized.


                                           SWIFT ENERGY INCOME
                                           PARTNERS 1986-D, LTD.
                                           (Registrant)

                                By:        SWIFT ENERGY COMPANY
                                           Managing General Partner

Date:     August 4, 1997        By:        /s/ John R. Alden
          --------------                   --------------------------------
                                           John R. Alden
                                           Senior Vice President, Secretary
                                           and Principal Financial Officer

Date:     August 4, 1997        By:        /s/ Alton D. Heckaman, Jr.
          --------------                   --------------------------------
                                           Alton D. Heckaman, Jr.
                                           Vice President, Controller
                                           and Principal Accounting Officer


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