<PAGE>   1

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                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM 10-K

[X]  ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
     ACT OF 1934 FOR THE FISCAL YEAR ENDED JUNE 30, 2000.

                               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 NO. 0-8565

                             MARINE PETROLEUM TRUST
             (Exact name of registrant as specified in its charter)

<TABLE>
<S>                                            <C>
                    TEXAS                                        75-6008017
       (State or other jurisdiction of                        (I.R.S. Employer
        incorporation or organization)                      Identification No.)
</TABLE>

                           C/O THE CORPORATE TRUSTEE:
                             BANK OF AMERICA, N.A.
                   P.O. BOX 830241, DALLAS, TEXAS 75283-0241
              (Address of principal executive offices) (Zip Code)

               Registrant's telephone number, including area code
            (at the office of the Corporate Trustee): (800) 985-0794

          Securities registered pursuant to Section 12(b) of the Act:

                                      NONE

          Securities registered pursuant to Section 12(g) of the Act:

                          UNITS OF BENEFICIAL INTEREST
                                (TITLE OF CLASS)

     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, and (2) has been subject to such filing
requirements for the past 90 days.

                                YES  X    NO
                                    ---      ---

     Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K.  [X]

     Aggregate market value of Units of Beneficial Interest held by
non-affiliates of the registrant at September 21, 2000: $36,412,534.

     Number of Units of Beneficial Interest outstanding as of September 21,
2000 -- 2,000,000 Units.

                      Documents Incorporated by Reference:

                                      NONE

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<PAGE>   2

                             CROSS-REFERENCE SHEET

     This Form 10-K for the year ended June 30, 2000 of Marine Petroleum Trust
is not organized by conventional item numbers and headings contemplated by SEC
rules and forms. This cross-reference page is intended to indicate to the reader
where (or under which headings) information required under Form 10-K may be
found herein.

<TABLE>
<CAPTION>
 FORM 10-K                                                                   HEADINGS
ITEM NUMBERS                                                                  HEREIN
------------                                                                 --------
<S>         <C>                                               <C>
PART I......................................................  General
  Item  1.  Business........................................  The Trust; Properties
  Item  2.  Properties......................................  Properties
  Item  3.  Legal Proceedings...............................  Legal Matters
  Item  4.  Submission of Matters to a Vote of Security
              Holders.......................................  Unitholder Voting Matters
PART II.....................................................  Financial
  Item  5.  Market for Registrant's Common Equity and
              Related Stockholder Matters...................  Market and Investor Information
  Item  6.  Selected Financial Data.........................  Selected Financial Data
  Item  7.  Management's Discussion and Analysis of
              Financial Condition and Results of
              Operations....................................  Management's Discussion and Analysis of
                                                                Financial Condition and Results of
                                                                Operations
  Item 7A.  Quantitative and Qualitative Disclosures About
              Market Risk...................................  Quantitative and Qualitative
                                                                Disclosures about Market Risk
  Item  8.  Financial Statements and Supplementary Data.....  Financial Statements and Supplementary
                                                                Data
  Item  9.  Disagreements on Accounting and Financial
              Disclosure....................................  Accounting Matters
PART III....................................................  Management and Principal Unitholders
  Item 10.  Directors and Executive Officers of the
              Registrant....................................  Administrators
  Item 11.  Management Remuneration.........................  Administrators; Management Compensation
  Item 12.  Security Ownership of Certain Beneficial Owners
              and Management................................  Principal Unitholders
  Item 13.  Certain Relationships and Related
              Transactions..................................  Administrators; Management Compensation
PART IV.....................................................  Miscellaneous
  Item 14.  Exhibits, Financial Statement Schedules and
              Reports on Form 8-K...........................  Exhibits, Financial Statement Schedules
                                                                and Reports on Form 8-K
</TABLE>
<PAGE>   3

                                    GENERAL

                                   THE TRUST

     Organization. Marine Petroleum Trust ("Marine") is a royalty trust created
in 1956 under the laws of the State of Texas. Marine is not permitted to engage
in any business activity inasmuch as it was organized for the sole purpose of
providing an efficient, orderly, and practical means for the administration and
liquidation of rights to payments from certain oil and gas leases in the Gulf of
Mexico, pursuant to license agreements and amendments thereto between Marine's
predecessors and Gulf Oil Corporation ("Gulf"). As a result of various
transactions that have occurred since 1956, the Gulf interests now are held by
Chevron Corporation ("Chevron"), Elf Exploration, Inc. ("Elf"), and their
assignees.

     The indenture pursuant to which Marine was created (the "Indenture"),
provides that the corporate trustee is to distribute all cash in Marine, less an
amount reserved for the payment of accrued liabilities and estimated future
expenses, to unitholders of record on the 28th day of September, December, March
and June of each fiscal year. If the 28th falls on a Saturday, Sunday or legal
holiday, the distribution is payable on the immediately preceding business day.

     The Indenture also provides that the term of the royalty trust created
thereby will expire on June 1, 2001 unless extended by the vote of the holders
of a majority of the outstanding units of beneficial interest. Following the
filing of this Annual Report, the unitholders will be asked to approve an
amendment to the Indenture to extend the life of Marine beyond the expiration
date.

     Marine's wholly-owned subsidiary, Marine Petroleum Corporation ("MPC"),
holds title to interests in properties subject to Marine's interests that are
situated offshore of Louisiana. Ninety-eight percent of all oil, gas, and other
mineral royalties collected by this subsidiary are paid to Marine. MPC, like
Marine, is prohibited from engaging in a trade or business and does only those
things necessary for the administration and liquidation of its properties.

     Marine's only industry segment or purpose is the administration and
collection of royalties.

     Royalties. Marine's rights are generally referred to as overriding royalty
interests in the oil and gas industry, and are sometimes referred to herein as
such. All production and marketing functions are conducted by the working
interest owners of the leases. Revenues from the overriding royalties are paid
to Marine either (i) on the basis of the selling price of oil, gas and other
minerals produced, saved and sold, or (ii) at the value at the wellhead as
determined by industry standards, when the selling price does not reflect the
value at the wellhead.

     The contracts creating these interests were entered into between
predecessors of Marine and Gulf, and relate to two different types of interests.
One type of interest is an overriding royalty interest equal to three-fourths of
1% of the value at the well of any oil, gas, or other minerals produced and
sold. Marine's overriding royalty interest applies only to existing leases and
does not apply to new leases. The second interest is Marine's 32.6% equity
interest in Tidelands Royalty Trust "B" ("Tidelands"), a separate Texas trust,
which owns similar interests in any oil, gas, or other mineral lease acquired by
Gulf and/or its transferees and assignees in a 1,370,000-acre area (divided into
60 tracts) of the Gulf of Mexico (the "Royalty Area") during a 50-year period
ending April 30, 2001. Tidelands' interest in each tract consists of (i) a
production payment, which reverts to an overriding royalty, on oil and gas and
(ii) an overriding royalty on other minerals. The production payment is payable
out of 12.5% of the value at the well of oil and gas produced and sold from
leases on a subject tract until Tidelands has earned $1,500,000 on such tract.
The production payment then reverts to an overriding royalty interest equal to
approximately 4.17% of the value at the well of oil and gas sold from the tract.
Tidelands' overriding royalty interest on minerals other than oil and gas is
payable at the rate of 4.17% of the value of such minerals sold from the
property. Marine, through its ownership of units of beneficial interest in
Tidelands, derives a 32.6% interest in the production payments and overriding
royalties of Tidelands.

     Presently, the leases subject to Marine's interests cover 272,913 gross
acres (including Tidelands' interest in 27,312 leased acres). These leases will
remain in force until the expiration of their respective terms. Leases may be
voluntarily released by the working interest owner after all oil and gas
reserves are produced. They may also be abandoned by the working interest owner
due to failure to discover sufficient reserves to make
<PAGE>   4

development economically worthwhile. In addition, the federal government may
force termination if the working interest owner fails to fully develop a lease
once it is acquired.

     For the year ended June 30, 2000, approximately 53% of Marine's royalty
revenues were attributable to the sale of oil and approximately 47% were
attributable to the sale of natural gas. The royalty revenues received by Marine
are affected by seasonal fluctuations in demand and by changes in the market
price for oil and gas. Royalty revenue received by Marine from Chevron and from
Pennzenergy Exploration and Production Company ("Pennzenergy") accounted in the
aggregate for approximately 81%, 76% and 85%, of Marine's royalty revenue for
the years ended June 30, 2000, 1999, and 1998, respectively. Chevron accounted
for 71%, 55% and 63% of Marine's royalty revenue for the fiscal years ended June
30, 2000, 1999 and 1998, respectively. Pennzenergy accounted for 10%, 21% and
22% of Marine's royalty revenue for the fiscal years ended June 30, 2000, 1999
and 1998, respectively. In addition, Marine's revenue from its equity interest
in Tidelands accounted for approximately 6%, 10% and 15%, of Marine's revenue
for the years ended June 30, 2000, 1999, and 1998, respectively. Tidelands has
reported that royalty revenues from American Explorer Company, Burlington
Resources, Chevron and Pennzenergy accounted for a substantial portion of
Tidelands' royalty revenue for the years ended December 31, 1999, 1998, and
1997.

     Marine derives no revenues from foreign sources and has no export sales.

     Trust Functions. Marine is administered by officers and employees of its
Trustee, Bank of America, N.A. MPC employs one individual (its president,
treasurer and director) to perform certain management, financial and
administrative services for Marine. Except for this individual, all officers and
directors of MPC serve without compensation. See "Management and Principal
Unitholders."

     Important aspects of Marine's operations are conducted by third parties.
These include the production and sale of oil and gas and the calculation of
royalty payments to Marine, which are conducted by oil and gas companies that
lease tracts subject to Marine's interests. Similarly, Marine's distributions
are processed and paid by The Bank of New York as the agent for the trustee of
Marine.

     MPC leases office space in Dallas, Texas to provide work space and record
storage for Marine, MPC, Tidelands and Tidelands' wholly-owned subsidiary
corporation, Tidelands Royalty "B" Corporation. The cost of this office facility
is shared by all four of these entities in proportion to each entity's gross
income to the total of such income of all entities.

     The ability of Marine to receive revenues is entirely dependent upon its
entitlement to its rights with respect to the leases held by Chevron and its
assignees in the Gulf of Mexico (as more fully described in "Properties" below).
Moreover, no revenues are payable to Marine until sales of production commence
from any such lease.

     The royalty interests held by Marine are depleting with each barrel of oil
and mcf of natural gas produced. No funds are reinvested by Marine; thus, these
depleting assets are not being replaced.

                                   PROPERTIES

     General. Marine is not engaged in oil and gas operations, although its
income is based upon such operations of others. Marine's income is derived from
contracts that provide for payments in the nature of overriding royalties made
to Marine based on oil and gas sales from certain leases in the Gulf of Mexico.

     Reserves. Marine is not engaged in the production of crude oil or natural
gas. Its income is derived from overriding royalty payments which are carved out
of working interests in oil and gas leases in the Gulf of Mexico. Marine does
not have the engineering data necessary to make an estimate of proved oil and
gas reserves (nor the present value of future net cash flows from such
reserves), and is not entitled to receive such data from the owners of the
working interests from which Marine's interest is derived. See also "Difficulty
in Obtaining Certain Data" below.

     Since Marine does not have access to this reserve information, Marine is
unable to compute the standardized measure of discounted future net cash flows
therefrom.

                                        2
<PAGE>   5

     Marine did not file any reports during the fiscal year ended June 30, 2000
with any federal authority or agency with respect to oil and gas reserves.

     Production. Information regarding the net quantities of oil and gas
produced with respect to Marine's over-riding royalty interests (excluding its
equity in Tidelands and excluding the income realized from the reduction of the
amounts reserved for royalty over-payments) for each of the last three fiscal
years as well as the average sales price per unit of oil and gas produced, upon
which payments to Marine are based, is set forth in the following table:

<TABLE>
<CAPTION>
                                                             YEAR ENDED JUNE 30,
                                                        -----------------------------
                                                         2000      1999(1)    1998(1)
                                                        -------    -------    -------
<S>                                                     <C>        <C>        <C>
Quantity
  Oil (in barrels ("bbls"))...........................   92,837     57,575     59,343
  Gas (in thousand cubic feet ("mcf"))................  807,837    869,636    582,594
Average Price
  Oil (per bbl).......................................   $24.51     $12.54     $15.97
  Gas (per mcf).......................................    $2.48      $1.85      $2.56
</TABLE>

-------------------------

(1) Prior year numbers have been revised to conform to the current year's
    presentation.

     Information about average production cost (lifting cost) per unit of
production has been omitted due to its unavailability and inapplicability to
Marine. For more recent information regarding prices, see "Management's
Discussion and Analysis of Financial Condition and Results of Operations" below.

     Productive Wells. Based on the latest information available to Marine and
including its equity interest in Tidelands, there were approximately 322 wells
subject to Marine's interests actually producing at some time in calendar 1999,
some of which contained multiple completions. During calendar 1999,
approximately 126 wells produced oil and approximately 196 wells produced gas.
Most of the oil wells also produced associated gas and most of the gas wells
produced condensate, which is economically the equivalent of oil. See
"Difficulty in Obtaining Certain Data" below.

     Drilling Activity. Information concerning the results of operations on
leases in which Marine had an interest (including its equity interest in
Tidelands) for each of its last three fiscal years is set forth below:

<TABLE>
<CAPTION>
                                                                YEAR ENDED JUNE 30,
                                                             --------------------------
                                                             2000    1999(1)    1998(1)
                                                             ----    -------    -------
<S>                                                          <C>     <C>        <C>
Development
  Oil......................................................   21       24         13
  Gas......................................................   36       36         23
  Suspended*...............................................    6        4         13
  Dry......................................................    5       10          8
                                                              --       --         --
       Totals..............................................   68       74         57
                                                              ==       ==         ==
</TABLE>

---------------

 *  "Suspended" wells are completed wells the classification of which had not
    been reported at the relevant date.

(1) Prior year numbers have been revised to conform to the current year's
    presentation.

     Information regarding net wells or acres is not included since Marine does
not own any working interests.

                                        3
<PAGE>   6

     Lease Acreage. Marine has an overriding royalty interest (including by
virtue of its equity interest in Tidelands) in 73 different oil and gas leases
covering 272,913 gross acres. These leases are located in the Central and
Western areas of the Gulf of Mexico off the coasts of Louisiana and Texas. This
acreage is presented in the following table:

<TABLE>
<CAPTION>
                   LEASES GRANTED BY (1):                     PRODUCING
                   ----------------------                     ---------
<S>                                                           <C>
United States...............................................   267,383
State of Texas..............................................       640
State of Louisiana..........................................     4,890
                                                               -------
                                                               272,913
                                                               =======
</TABLE>

---------------

(1) Leases are typically granted for a term of five years, during which the
    lease owner must establish a commercial production capability, or the lease
    expires. There are 9,305 acres located on leases that have commercial
    production, but the production is not on Marine's overriding royalty area
    within those leases.

The overriding royalty interest owned by Marine is a fractional interest out of
total oil and gas sold, and is free and clear of all operating costs. The actual
percentage interest in a lease attributable to Marine's interest varies from
lease to lease. The acreage weighted average percentage interest attributable to
Marine's interest in all of these leases is .5864%.

     Present Activities. Published reports from third parties indicate that 10
wells are being drilled on tracts in which Marine has an interest. Marine also
understands from published reports of third parties that operators have
designated locations for 14 additional wells. Marine cannot assure the
unitholders that these wells will be drilled and if drilled that they will be
successful.

     The U.S. Department of the Interior conducted a lease sale for the Gulf of
Mexico in April and August, 2000. Chevron did not bid on any tracts included in
this sale that are located in the 1,370,000 acre area subject to the Tidelands
contract (in which Marine has a 32.6% equity interest.)

     Difficulty in Obtaining Certain Data. Marine's only activities are the
collection and distribution of revenues from overriding royalties on certain oil
and gas leases in the Gulf of Mexico, pursuant to purchase agreements between
Marine's predecessors and Gulf and its transferees. The leasehold working
interests which are subject to the rights held by Marine are owned, in most
cases, in whole or in part by Chevron, or other oil and gas exploration and
production companies. Certain information as to reserves, availability of oil
and gas, average production cost (lifting cost) per unit, undeveloped acreage,
net wells and net acres, etc., with respect to the particular leases subject to
Marine's interests lies solely within the knowledge of these concerns.
Engineering data, if any, regarding these leaseholds would have been compiled
principally by or for the working interest owners of these leaseholds and Marine
believes that it will not be provided access to such information. Because of
this, it appears that unreasonable efforts and expense would be involved in
seeking to obtain all of the information required under Item 102 of Regulation
S-K and Securities Exchange Act of 1934 Industry Guide 2.

                                 LEGAL MATTERS

     Neither Marine nor MPC, nor any of their respective properties (exclusive
of properties owned by Chevron and subject to the Marine and Tidelands license
agreements), is a party to or subject to any material pending litigation as of
the date hereof.

                           UNITHOLDER VOTING MATTERS

     No matter was submitted by Marine during the year ended June 30, 2000 to a
vote of unitholders, whether through the solicitation of proxies or otherwise.

     Following the filing of this Annual Report with the SEC, the unitholders
will be asked to approve an amendment to the Indenture to extend the life of the
trust beyond the current expiration date of June 1, 2001.

                                        4
<PAGE>   7

     Marine is to continue until June 1, 2001, or until such later date as
holders of the units owning a majority of the outstanding units may designate,
but in any event, not more than 20 years from such designation. Alternatively,
instead of so extending the term of Marine, the holders of the units owning a
majority of the outstanding units may direct the Trustee to create one or more
corporations to receive and hold the trust estate, or any portion thereof,
unless the Trustee shall have received written objection from any unitholder
within 20 days from the date of mailing to the unitholders of the first notice
of the proposed consent. However, the unitholders owning eighty percent (80%) of
the outstanding units may terminate the trust on any date, whether earlier or
later than any such date determined as above, as they may specify.

     If the Indenture is not extended then the trust underlying Marine will be
terminated. Upon termination of the trust (other than by the transfer of all the
trust estate to a corporation pursuant to the provisions of the Indenture, as
described above), the Trustee, after paying all of the obligations of the trust,
shall transfer to an agent appointed by the holders of the units owning a
majority of the outstanding units, by recordable assignments but without
warranty, the interests in the trust estate. Prior to termination of the trust,
no unitholder shall have any legal title in or to any of the properties
comprising the trust estate nor the right to secure any partition thereof.

     Unitholders owning ten percent (10%) or more of the outstanding units may
at any time direct the Trustee to conduct an investigation to determine whether
the Trustee is receiving all revenues properly accruing to Marine's trust
estate. The Trustee may be removed by unitholders owning a majority of the
outstanding units. The unitholders owning eighty percent (80%) of the
outstanding units may amend and modify the Indenture or any contract, agreement
or undertaking which constitutes a part of the trust estate, but no such
amendment may change the nature of the trust from that of a purely ministerial
trust, nor can there be any change in the rights or responsibilities of the
Trustee without its consent. However, no such change shall be made with respect
to any amendment to the Indenture if the Trustee shall receive written objection
from any unitholder within 20 days from the date of mailing to the unitholders
of the first notice of the proposed consent. Each unitholder has the right to
examine, inspect and audit all records relating to the trust estate.

                                   FINANCIAL

                        MARKET AND INVESTOR INFORMATION

     The units of beneficial interest in Marine trade on the Nasdaq SmallCap
Market under the symbol "MARPS". Distributions of cash are made to unitholders
quarterly. The following table presents the range of high and low trade prices
by quarter for the past two years as reported by the OTC Market Report. The per
unit amount of cash distributed to unitholders for each of these quarters is
also presented in the table.

<TABLE>
<CAPTION>
                                                         TRADE PRICE
                                                      ------------------    DISTRIBUTIONS
                   QUARTER ENDING                      HIGH        LOW        PER UNIT
                   --------------                     -------    -------    -------------
<S>                                                   <C>        <C>        <C>
September 30, 1999..................................   15.750     13.875         .436
December 31, 1999...................................   15.750     13.500         .517
March 31, 2000......................................   16.000     13.750         .555
June 30, 2000.......................................   15.938     14.500         .643
September 30, 1998..................................   17.500     12.125         .326
December 31, 1998...................................   15.250     12.500         .406
March 31, 1999......................................   15.000     12.375         .305
June 30, 1999.......................................   19.000     13.500         .352
</TABLE>

     Marine is authorized to issue and has issued 2,000,000 units of beneficial
interest. On September 12, 2000, these outstanding units were held of record by
684 unitholders.

                                        5
<PAGE>   8

     Marine must distribute to its unitholders all cash accumulated each
quarter, less an amount reserved for accrued liabilities and estimated future
expenses. Such distributions have been made since the third quarter of 1977 and
will continue so long as the income from oil and gas royalties exceeds
administrative costs.

     Distributions fluctuate from quarter to quarter due to changes in oil and
gas prices and production quantities. Distributions, however, are determined by
the cash available to Marine on the determination date.

                            SELECTED FINANCIAL DATA

<TABLE>
<CAPTION>
                                                    (IN THOUSANDS EXCEPT PER UNIT AMOUNTS)
                                                ----------------------------------------------
                                                 2000      1999      1998      1997      1996
                                                ------    ------    ------    ------    ------
<S>                                             <C>       <C>       <C>       <C>       <C>
STATEMENT OF INCOME AND UNDISTRIBUTED INCOME
  SELECTED DATA
  Income:
     Oil and gas royalties....................   4,526    $2,841    $2,577    $3,645    $2,842
     Equity in Tidelands......................     318       328       461       319       385
     Interest.................................      92        98       100       101        92
                                                ------    ------    ------    ------    ------
                                                 4,936    $3,267    $3,138    $4,065    $3,319
                                                ------    ------    ------    ------    ------
  Expenses:
     General and administrative...............     180    $  176    $  146    $  143    $  121
     Federal income taxes of subsidiary.......      12         6        12         8        12
                                                ------    ------    ------    ------    ------
                                                   192    $  182    $  158    $  151    $  133
                                                ------    ------    ------    ------    ------
     Net income...............................   4,744    $3,085    $2,980    $3,914    $3,186
                                                ======    ======    ======    ======    ======
     Distributions............................   4,300    $2,777    $3,216    $3,939    $2,548
                                                ======    ======    ======    ======    ======
  Per Unit (2,000,000 outstanding)
     Net income...............................  $ 2.37    $ 1.54    $ 1.49    $ 1.96    $ 1.59
                                                ======    ======    ======    ======    ======
     Distributions............................  $ 2.15    $ 1.39    $ 1.61    $ 1.97    $ 1.27
                                                ======    ======    ======    ======    ======
BALANCE SHEET SELECTED DATA
  Total assets................................  $2,570    $2,371    $2,745    $2,945    $2,979
                                                ======    ======    ======    ======    ======
  Trust equity................................  $2,560    $2,117    $1,809    $2,045    $2,070
                                                ======    ======    ======    ======    ======
</TABLE>

                                        6
<PAGE>   9

                    MANAGEMENT'S DISCUSSION AND ANALYSIS OF
                 FINANCIAL CONDITION AND RESULTS OF OPERATIONS

     Capital Resources and Liquidity. Because of the nature of Marine as a trust
entity, there is no requirement for capital; its only obligation is to
distribute to unitholders the net income actually collected. As an administrator
of oil and gas royalty properties, Marine collects income monthly, pays expenses
of administration, and disburses all net income collected to its unitholders
each quarter.

     Marine's Indenture (and the charter and by-laws of MPC) expressly prohibits
the operation of any kind of trade or business. Marine's oil and gas properties
are depleting assets and are not being replaced due to the prohibition against
these investments. These restrictions, along with other factors, allow Marine to
be treated as a grantor trust; thus all income and deductions, for tax purposes,
should flow through to each individual unitholder. Marine is not a taxable
entity.

     Results of Operations. Marine's revenues are derived from the oil and gas
production activities of unrelated parties. Marine's revenues and distributions
fluctuate from period to period based upon factors beyond Marine's control,
including without limitation the number of leases bid on and obtained by parties
subject to Marine's interests, the number of productive wells drilled on leases
subject to Marine's interests, the level of production over time from such wells
and the prices at which the oil and gas from such wells is sold. Marine believes
that it will continue to have revenues sufficient to permit distributions to be
made to unitholders for the foreseeable future, although no assurance can be
made regarding the amounts thereof. The foregoing sentence is a forward-looking
statement. Factors that might cause actual results to differ from expected
results include reductions in prices or demand for oil and gas, which might then
lead to decreased production; reductions in production due to depletion of
existing wells or disruptions in service, including as the result of storm
damage, blowouts or other production accidents, and geological changes such as
cratering of productive formations; expiration or release of leases subject to
Marine's interests; and the discontinuation by parties subject to Marine's
interests of their efforts to obtain leases in the Royalty Area.

     Marine's income consists primarily of oil and gas royalties and is based on
the value at the well of its percentage interest in oil and gas sold without
reduction for any of the expense of production. Value at the well for oil is the
purchasers' posted price at its receiving point onshore, less the cost of
transportation from the offshore lease to the onshore receiving point. In
general, value at the well is determined on the basis of the selling price of
oil, gas and other minerals produced, saved and sold, or at wellhead prices
determined by industry standards, where the selling price does not reflect value
at the well.

     Summary Review. Marine's net income for the year ended June 30, 2000
amounted to $4,743,594 or $2.37 per unit as compared to $3,084,449 or $1.54 per
unit in fiscal 1999 and $2,980,458 or $1.49 per unit in fiscal 1998. These
results include $244,250, $514,000 and $137,474 realized in fiscal 2000, 1999
and 1998, respectively, from reduction of an accounts payable provided by MPC to
cover possible refunds that may have been required upon redetermination of gas
prices for royalty payments in prior periods. During fiscal 2000 MPC determined
that the accounts payable was no longer required and accordingly reduced the
accounts payable to zero and increased income before federal income taxes by
$244,250.

     These results also include income from Marine's equity interest in
Tidelands which amounted to $318,072 for fiscal 2000, and for fiscal 1999 and
1998 it was $328,085 and $461,095, respectively. Income from Tidelands
contributed approximately 6% of Marine's royalty income for fiscal 2000 as
compared to 10% and 15% of Marine's royalty income for fiscal 1999 and fiscal
1998, respectively.

     Marine's administrative expenses and interest income were approximately the
same during the past three years. The changes in net income are primarily the
result of changes in oil and gas royalties.

     Higher oil prices and increased production during fiscal 2000 resulted in
an increase in oil royalties over the amount realized in fiscal 1999. Oil
royalties declined in fiscal 1999 from the amounts realized in fiscal 1998 due
to a decrease in the price received for oil and a decline in production.

     Higher gas prices and increased production during fiscal 2000 resulted in
an increase in gas royalties over those realized in fiscal 1999. While gas
prices declined in fiscal 1999, the decrease was offset by an increase in
production, which produced an increase in gas royalties over those realized in
fiscal 1998.

                                        7
<PAGE>   10

     Marine believes that the drilling and work-over program of the operating
companies, which has resulted in an average of 66 new completions over the past
three years, is primarily responsible for maintaining the number of producing
wells at approximately 300 for the past three fiscal years.

     The following table and related discussion and analysis shows the royalty
income, the net quantities sold, and the average price received for oil and gas
during the past three years excluding Marine's equity interest in Tidelands and
the $244,250, $514,000 and $137,474 realized in fiscal 2000, fiscal 1999 and
fiscal 1998, respectively, from the reduction of the previously established
accounts payable for possible royalty over-payments that management no longer
deemed required.

<TABLE>
<CAPTION>
                                                         FOR YEARS ENDED JUNE 30
                                                   ------------------------------------
                                                      2000       1999(1)      1998(1)
                                                   ----------   ----------   ----------
<S>                                                <C>          <C>          <C>
Income from
  Oil royalties..................................  $2,275,447   $  721,782   $  947,656
  Gas royalties..................................   2,006,664    1,604,772    1,491,996
                                                   ----------   ----------   ----------
          Totals.................................  $4,282,111   $2,326,554   $2,439,652
                                                   ----------   ----------   ----------
Net quantities sold
  Oil (bbls).....................................      92,837       57,575       59,343
  Gas (mcf)......................................     807,837      869,636      582,594
Average price
  Oil............................................  $    24.51   $    12.54   $    15.97
  Gas............................................  $     2.48   $     1.85   $     2.56
</TABLE>

---------------

(1) 1999 and 1998 numbers have been revised to conform to the current year's
    presentation.

     Oil and Gas Royalties  -- 2000 and 1999: During fiscal 2000, Marine
received approximately 53% of its royalty income from the sale of oil and 47%
from the sale of natural gas. Income from such oil and gas royalties in fiscal
2000 increased approximately 84% from fiscal 1999.

     Oil royalties during fiscal 2000 in the amount of $2,275,447 were 215% more
than oil royalties received in fiscal 1999 in the amount of $721,782, due to an
increase in the quantity of oil sold and in the average price received.

     Natural gas royalties during fiscal 2000 in the amount of $2,006,664 were
25% higher than natural gas royalties received in fiscal 1999 in the amount of
$1,604,772. The increase was due to an increase in the price received that was
partially offset by a decrease in the quantity of natural gas sold.

     Oil and Gas Royalties -- 1999 and 1998: During fiscal 1999, Marine received
31% of its royalty income from the sale of oil and 69% from the sale of natural
gas. Income from such oil and gas royalties in fiscal 1999 decreased 5% from
fiscal 1998.

     Oil royalties during fiscal 1999 in the amount of $721,782 were 24% less
than oil royalties received in fiscal 1998 in the amount of $947,656.

     Natural gas royalties during fiscal 1999 in the amount of $1,604,772 were
8% more than natural gas royalties received in fiscal 1998 in the amount of
$1,491,996.

                                        8
<PAGE>   11

           QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

     At June 30, 2000, Marine did not have any market risk exposure with regard
to any activities in derivative financial instruments, other financial
instruments and derivative commodity instruments.

                  FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

     The financial statements listed in the following Index, together with the
related notes and the report of KPMG LLP, independent certified public
accountants, are presented on pages 12 through 18 hereof.

<TABLE>
<CAPTION>
                                                              PAGE
                                                              ----
<S>                                                           <C>
Independent Auditors' Report................................   12
Financial Statements:
  Consolidated Balance Sheets as of June 30, 2000 and
     1999...................................................   13
  Consolidated Statements of Income and Undistributed Income
     for the Three Years Ended June 30, 2000................   14
  Consolidated Statements of Cash Flows for
     the Three Years Ended June 30, 2000....................   15
  Notes to Consolidated Financial Statements................   16
</TABLE>

     See also "Exhibits, Financial Statement Schedules and Reports on Form 8-K"
of this Form 10-K for further information concerning the financial statements of
Marine and its subsidiaries.

     All schedules have been omitted for the reason that they are either not
required, not applicable or the required information is included in the
financial statements and notes thereto.

                               ACCOUNTING MATTERS

     During fiscal 2000 and 1999, there have been no disagreements between
Marine and its independent auditors on accounting or financial disclosure
matters which would warrant disclosure under Item 304 of Regulation S-K.

                                        9
<PAGE>   12

                      MANAGEMENT AND PRINCIPAL UNITHOLDERS

                                 ADMINISTRATORS

     Marine is a trust created under the laws of the State of Texas. Marine's
Indenture does not provide for directors or officers or the election of
directors or officers. Under the Indenture, Bank of America, N.A., serves as
Trustee.

     R. Ray Bell may be considered a significant employee of Marine. Mr. Bell
has been involved in the administration of Marine since its inception. He was
the chief financial officer of Marine's predecessor and is 73 years old. Since
July 1, 1977, he has served as an officer and director of MPC, and will continue
to serve in such capacities until the next meeting of directors and
shareholders, respectively, of MPC or until his successors are elected and
qualified.

                            MANAGEMENT COMPENSATION

     During the fiscal year ended June 30, 2000, Marine paid or accrued fees of
$26,188 to Bank of America, N.A., as Trustee. These fees are paid in accordance
with the terms of the Indenture, as amended, governing Marine.

                             PRINCIPAL UNITHOLDERS

     The following table sets forth the persons known to Marine who own
beneficially more than five percent of the outstanding units of beneficial
interest as of June 30, 2000:

<TABLE>
<CAPTION>
                                          AMOUNT AND NATURE OF   PERCENT
  TITLE OF CLASS      NAME AND ADDRESS    BENEFICIAL OWNERSHIP   OF CLASS
  --------------      ----------------    --------------------   --------
<S>                  <C>                  <C>                    <C>
Units of Beneficial  L. C. Paslay          286,469 units,          14.32%
  Interest           1020 S. Ocean Blvd.   owned
                     Manalapan, FL 33462   of record
                                           and beneficially*
</TABLE>

---------------

* Does not include 27,225 units held in trust in the name of L. C. Paslay, as
  Co-Trustee with Bank of America, N.A., for the benefit of Patricia L. Martin,
  daughter of Mr. Paslay.

     There are no executive officers or directors of Marine. Bank of America,
N.A. does not beneficially own any units of beneficial interest.

                                       10
<PAGE>   13

                                 MISCELLANEOUS

        EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

     (a) Financial Statements -- see "Financial Statements and Supplementary
Data" above.

     The consolidated financial statements, together with the related notes and
the report of KPMG LLP, independent certified public accountants, as contained
in the Form 10-K of Tidelands Royalty Trust "B" for its fiscal year ended
December 31, 1999 and filed with the Securities and Exchange Commission, are
hereby incorporated herein by reference for all purposes.

     (b) Reports on Form 8-K -- No reports on Form 8-K have been filed during
the last quarter of the fiscal year ended June 30, 2000.

     (c) Exhibits:

<TABLE>
<S>                   <C>
           3.1        -- Indenture, as amended, of Marine, filed as Exhibit 3 to the Annual Report on Form
                         10-K of Marine Petroleum Trust for the fiscal year ended June 30, 1994, filed with
                         the Securities and Exchange Commission and incorporated by reference herein.
           4.1        -- Form of Certificate evidencing Unit(s) of Beneficial Interest, filed as Exhibit 4 to
                         the Annual Report on Form 10-K of Marine Petroleum Trust for the fiscal year ended
                         June 30, 1994, filed with the Securities and Exchange Commission and incorporated by
                         reference herein.
          21.1        -- Subsidiaries of Marine.
          27.1        -- Financial Data Schedule.
</TABLE>

                                       11
<PAGE>   14

                          INDEPENDENT AUDITORS' REPORT

The Trustee
Marine Petroleum Trust:

     We have audited the accompanying consolidated balance sheets of Marine
Petroleum Trust and subsidiary as of June 30, 2000 and 1999 and the related
consolidated statements of income and undistributed income and cash flows for
each of the years in the three-year period ended June 30, 2000. These financial
statements are the responsibility of the Trust's management. Our responsibility
is to express an opinion on these financial statements based on our audits.

     We conducted our audits in accordance with auditing standards generally
accepted in the United States of America. Those standards require that we plan
and perform the audit to obtain reasonable assurance about whether the financial
statements are free of material misstatement. An audit includes examining, on a
test basis, evidence supporting the amounts and disclosures in the financial
statements. An audit also includes assessing the accounting principles used and
significant estimates made by management, as well as evaluating the overall
financial statement presentation. We believe that our audits provide a
reasonable basis for our opinion.

     In our opinion, the consolidated financial statements referred to above
present fairly, in all material respects, the financial position of Marine
Petroleum Trust and subsidiary as of June 30, 2000 and 1999 and the results of
their operations and their cash flows for each of the years in the three-year
period ended June 30, 2000, in conformity with accounting principles generally
accepted in the United States of America.

                                            /s/ KPMG LLP

Dallas, Texas
September 15, 2000

                                       12
<PAGE>   15

                     MARINE PETROLEUM TRUST AND SUBSIDIARY

                          CONSOLIDATED BALANCE SHEETS
                             JUNE 30, 2000 AND 1999

                                     ASSETS

<TABLE>
<CAPTION>
                                                                 2000            1999
                                                              ----------      ----------
<S>                                                           <C>             <C>
Current assets:
  Cash and cash equivalents.................................  $1,681,598      $1,659,864
  Oil and gas royalties receivable..........................     486,708         307,657
  Receivables from affiliate (note 2).......................      95,002          80,939
                                                              ----------      ----------
          Total current assets..............................   2,263,308       2,048,460
                                                              ----------      ----------
Investment in affiliate (note 2)............................     306,401         322,070
Office equipment, net.......................................         555             555
Producing oil and gas properties............................           7               7
                                                              ----------      ----------
                                                               2,570,271      $2,371,092
                                                              ==========      ==========

                              LIABILITIES AND TRUST EQUITY

Current liabilities:
  Accounts payable (note 3).................................  $       88      $  244,250
  Income taxes payable......................................      10,182          10,156
                                                              ----------      ----------
          Total liabilities.................................      10,270         254,406
                                                              ----------      ----------
Trust equity:
  Corpus -- authorized 2,000,000 units of beneficial
     interest, issued 2,000,000 units at nominal value......           8               8
  Undistributed income......................................   2,559,993       2,116,678
                                                              ----------      ----------
          Total trust equity................................   2,560,001       2,116,686
                                                              ----------      ----------
                                                              $2,570,271      $2,371,092
                                                              ==========      ==========
</TABLE>

          See accompanying notes to consolidated financial statements.

                                       13
<PAGE>   16

                     MARINE PETROLEUM TRUST AND SUBSIDIARY

           CONSOLIDATED STATEMENTS OF INCOME AND UNDISTRIBUTED INCOME
                        THREE YEARS ENDED JUNE 30, 2000

<TABLE>
<CAPTION>
                                                            2000          1999          1998
                                                         ----------    ----------    ----------
<S>                                                      <C>           <C>           <C>
Income:
  Oil and gas royalties................................  $4,526,361    $2,840,554    $2,577,126
  Equity in earnings of affiliate (note 2).............     318,072       328,085       461,095
  Interest income......................................      92,399        97,929        99,915
                                                         ----------    ----------    ----------
                                                          4,936,832     3,266,568     3,138,136
Expenses:
  General and administrative...........................     180,832       176,169       146,366
                                                         ----------    ----------    ----------
          Income before federal income taxes...........   4,756,000     3,090,399     2,991,770
Federal income taxes of subsidiary.....................      12,406         5,950        11,312
                                                         ----------    ----------    ----------
          Net income...................................   4,743,594     3,084,449     2,980,458
Undistributed income at beginning of year..............   2,116,678     1,809,260     2,044,795
                                                         ----------    ----------    ----------
                                                          6,860,272     4,893,709     5,025,253
Distributions to unitholders...........................   4,300,279     2,777,031     3,215,993
                                                         ----------    ----------    ----------
Undistributed income at end of year....................  $2,559,993    $2,116,678    $1,809,260
                                                         ==========    ==========    ==========
Net income per unit....................................  $     2.37    $     1.54    $     1.49
                                                         ==========    ==========    ==========
Distributions per unit.................................  $     2.15    $     1.39    $     1.61
                                                         ==========    ==========    ==========
</TABLE>

          See accompanying notes to consolidated financial statements.

                                       14
<PAGE>   17

                     MARINE PETROLEUM TRUST AND SUBSIDIARY

                     CONSOLIDATED STATEMENTS OF CASH FLOWS
                        THREE YEARS ENDED JUNE 30, 2000

<TABLE>
<CAPTION>
                                                         2000           1999           1998
                                                      -----------    -----------    -----------
<S>                                                   <C>            <C>            <C>
Cash flows from operating activities:
  Net income........................................  $ 4,743,594    $ 3,084,449    $ 2,980,458
  Adjustments to reconcile net income to net cash
     provided by operating activities:
     Depreciation...................................           --             --          1,936
     Equity in undistributed earnings of
       affiliate....................................       15,669        (15,400)       (21,192)
     Change in assets and liabilities:
       Oil and gas royalties receivable.............     (179,051)        91,350        436,223
       Receivables from affiliate...................      (14,063)        35,438        (51,797)
       Accounts payable.............................     (244,162)      (682,413)        30,939
       Income taxes payable.........................           26          1,135          4,263
                                                      -----------    -----------    -----------
            Net cash provided by operating
               activities...........................    4,322,013      2,514,559      3,380,830

Cash flows used in investing activities -- purchase
  of office equipment...............................           --             --         (2,219)

Cash flows used in financing
  activities -- distributions to unitholders........   (4,300,279)    (2,777,031)    (3,215,993)
                                                      -----------    -----------    -----------

Net increase (decrease) in cash and cash
  equivalents.......................................       21,734       (262,472)       162,618
Cash and cash equivalents at beginning of year......    1,659,864      1,922,336      1,759,718
                                                      -----------    -----------    -----------

Cash and cash equivalents at end of year............  $ 1,681,598    $ 1,659,864    $ 1,922,336
                                                      ===========    ===========    ===========
</TABLE>

          See accompanying notes to consolidated financial statements.

                                       15
<PAGE>   18

                     MARINE PETROLEUM TRUST AND SUBSIDIARY

                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
                        THREE YEARS ENDED JUNE 30, 2000

(1) SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

  (a) General

     The Marine Petroleum Trust ("Marine") was established on June 1, 1956 with
the transfer of property to Marine consisting of certain contract rights, units
of beneficial interest and common stock in exchange for units of beneficial
interest in Marine. The contract rights entitled Marine to receive a .0075
overriding royalty interest in oil, gas and other mineral leasehold interests
acquired by Gulf Oil Corporation, now Chevron U.S.A., Inc. ("Chevron"), a
subsidiary of Chevron Corporation, in certain areas of the Gulf of Mexico prior
to January 1, 1980.

     Marine must distribute all income, after paying its liabilities and
obligations, to the unitholders during the months of March, June, September and
December each year. It cannot invest any of its money for any purpose and cannot
engage in a trade or business.

     A Louisiana trust can only exist for a short period of time; therefore, the
unitholders assigned their contract rights off-shore of Louisiana to Marine
Petroleum Corporation, a wholly-owned subsidiary of Marine, ("MPC") reserving a
98% net profits interest to themselves. The net profits interest contract was
transferred to Marine along with the other properties. Marine is authorized to
pay expenses of MPC should it be necessary.

     Marine is to continue until June 1, 2001, or until such later date as
holders of the units owning a majority of the outstanding units may designate,
but in any event, not more than 20 years from such designation. Alternatively,
instead of so extending the term of the trust, the holders of the units owning a
majority of the outstanding units may direct the Trustee to create one or more
corporations to receive and hold the trust estate, or any portion thereof,
unless the Trustee shall have received written objection from any unitholder
within 20 days from the date of mailing to the unitholders of the first notice
of the proposed consent. However, the unitholders owning eighty percent (80%) of
the outstanding units may terminate the trust on any date.

     Following the filing of this Annual Report with the SEC, the unitholders
will be asked to approve an amendment to the Indenture to extend the life of the
trust beyond the current expiration date of June 1, 2001.

  (b) Principles of Consolidation

     The consolidated financial statements include Marine and its wholly-owned
subsidiary, MPC. All material intercompany accounts and transactions have been
eliminated in consolidation.

  (c) Producing Oil and Gas Properties

     At the time Marine was established, no determinable market value was
available for the assets transferred to Marine; consequently, nominal values
were assigned. Accordingly, no allowance for depletion has been computed.

     All income from oil and gas royalties relate to proved developed oil and
gas reserves.

  (d) Undistributed Income

     Marine's indenture agreement provides that the corporate trustee is to
distribute all cash in the trust, less an amount reserved for the payment of
accrued liabilities and estimated future expenses, to unitholders of record on
the 28th day of March, June, September and December of each year. If the 28th
falls on a Saturday, Sunday or legal holiday, the distribution is payable on the
immediately preceding business day. Undistributed income includes $855,397 and
$785,532 applicable to MPC at June 30, 2000 and 1999, respectively.

                                       16
<PAGE>   19
                     MARINE PETROLEUM TRUST AND SUBSIDIARY

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
                        THREE YEARS ENDED JUNE 30, 2000

  (e) Federal Income Taxes

     No provision has been made for Federal income taxes on Marine's income
since such taxes are the liability of the unitholders. Federal income taxes have
been provided on the income of MPC, excluding the 98% net profits interest to be
distributed to Marine and deducting statutory depletion.

  (f) Credit Risk Concentration and Cash Equivalents

     Financial instruments which potentially subject Marine and MPC to
concentrations of credit risk are primarily investments in cash equivalents and
receivables. Marine and MPC place their cash investments with financial
institutions or companies that management considers credit worthy and limit the
amount of credit exposure from any one financial institution or company. Marine
has not experienced significant problems collecting its receivables in the past.

     Marine and MPC had cash equivalents of $1,611,902 and $1,640,570 at June
30, 2000 and 1999, respectively, which consisted of money market accounts and
money market mutual funds. For purposes of the statements of cash flows, Marine
considers all investments with initial maturities of three months or less to be
cash equivalents.

  (g) Statements of Cash Flows

     MPC made Federal income tax payments of $12,380, $4,815 and $7,049 during
the years ended June 30, 2000, 1999 and 1998, respectively.

  (h) Fair Value of Financial Instruments

     Marine and MPC define the fair value of a financial instrument as the
amount at which the instrument could be exchanged in a current transaction
between willing parties. The carrying value of cash equivalents, oil and gas
royalties receivable, receivables from affiliates, accounts payable, and taxes
payable approximate fair value because of the short maturities of those
instruments.

  (i) Use of Estimates

     Management of Marine and MPC has made a number of estimates and assumptions
relating to the reporting of assets and liabilities and the disclosure of
contingent assets and liabilities to prepare these financial statements in
conformity with generally accepted accounting principles. Actual results could
differ from those estimates.

  (j) Income Per Unit

     Income per unit is calculated by dividing net income by the weighted
average number of units of beneficial interest outstanding during the period.

  (k) Significant Royalty Sources

     Royalty revenue received by Marine from producers is summarized as follows:

<TABLE>
<S>                                                           <C>     <C>     <C>
                                                              2000    1999    1998
                                                              ----    ----    ----
Chevron.....................................................   71%     55%     63%
Pennzenergy.................................................   10%     21%     22%
Others......................................................   19%     24%     15%
                                                              ---     ---     ---
                                                              100%    100%    100%
                                                              ===     ===     ===
</TABLE>

                                       17
<PAGE>   20
                     MARINE PETROLEUM TRUST AND SUBSIDIARY

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
                        THREE YEARS ENDED JUNE 30, 2000

(2) INVESTMENT IN AND RECEIVABLES FROM AFFILIATE -- TIDELANDS ROYALTY TRUST "B"

     At June 30, 2000 and 1999, Marine owned 32.63% of the outstanding units of
interest in Tidelands Royalty Trust "B" ("Tidelands"). The 452,366 units owned
by Marine had a quoted market value of $1,837,737 and $2,233,557 at June 30,
2000 and 1999, respectively.

     Marine and Tidelands share certain common costs which are allocated based
on their respective net revenues.

     The investment in affiliate is accounted for by the equity method. The
following summarizes changes in this account for 2000 and 1999:

<TABLE>
<CAPTION>
                                                                2000         1999
                                                              ---------    ---------
<S>                                                           <C>          <C>
Balance at beginning of year................................  $ 322,070    $ 306,670
Equity in earnings of affiliate.............................    318,072      328,085
Distribution of earnings....................................   (333,741)    (312,685)
                                                              ---------    ---------
Balance at end of year......................................  $ 306,401    $ 322,070
                                                              =========    =========
</TABLE>

     At June 30, 2000 and 1999, receivables from affiliate includes $82,765 and
$68,212, respectively, of income distributable to Marine as a Tidelands
unitholder.

     The following summary financial statements have been derived from the
unaudited consolidated financial statements of Tidelands.

                                 BALANCE SHEETS

                                     ASSETS

<TABLE>
<CAPTION>
                                                                      JUNE 30
                                                              ------------------------
                                                                 2000          1999
                                                              ----------    ----------
<S>                                                           <C>           <C>
Cash and cash equivalents...................................  $1,448,800    $1,595,149
Oil and gas royalties receivable............................     104,632       129,418
Other.......................................................         579         3,476
                                                              ----------    ----------
                                                              $1,554,011    $1,728,043
                                                              ==========    ==========
</TABLE>

                          LIABILITIES AND TRUST EQUITY

<TABLE>
<S>                                                           <C>           <C>
Liabilities (including $262,797 and $218,194 payable to
  unitholders
  in 2000 and 1999, respectively)...........................  $  614,975    $  741,001
Corpus......................................................           2             2
Undistributed income........................................     939,034       987,040
                                                              ----------    ----------
                                                              $1,554,011    $1,728,043
                                                              ==========    ==========
</TABLE>

                                       18
<PAGE>   21
                     MARINE PETROLEUM TRUST AND SUBSIDIARY

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
                        THREE YEARS ENDED JUNE 30, 2000

                              STATEMENTS OF INCOME

<TABLE>
<CAPTION>
                                                            YEAR ENDED JUNE 30
                                                  --------------------------------------
                                                     2000          1999          1998
                                                  ----------    ----------    ----------
<S>                                               <C>           <C>           <C>
Income..........................................  $1,081,252    $1,149,611    $1,537,607
Expenses........................................      88,149        93,817       108,331
                                                  ----------    ----------    ----------
     Income before Federal income taxes.........     993,103     1,055,794     1,429,276
Federal income taxes of Tidelands' subsidiary...      18,285        11,765        16,150
                                                  ----------    ----------    ----------
     Net income.................................  $  974,818    $1,044,029    $1,413,126
                                                  ==========    ==========    ==========
</TABLE>

     Tidelands is a registrant with the Securities and Exchange Commission and
has filed a Form 10-K as of December 31, 1999.

(3) OVERPAID ROYALTIES

     During fiscal years 2000, 1999 and 1998, MPC determined that $244,250,
$514,000 and $137,474, respectively, of the previously-established accounts
payable for possible royalty overpayments was no longer deemed required.
Accordingly, during these fiscal years, MPC reduced accounts payable and
increased income before federal income taxes by such amounts.

(4) SUMMARY OF QUARTERLY FINANCIAL DATA (UNAUDITED)

     The following quarterly financial information for fiscal year 2000 and 1999
is unaudited; however, in the opinion of management, all adjustments necessary
to a fair statement of the results of operations for the interim periods have
been included.

<TABLE>
<CAPTION>
                                                                                     NET
                                             OIL AND GAS                            INCOME
                                              ROYALTIES    EXPENSES   NET INCOME   PER UNIT
                                             -----------   --------   ----------   --------
<S>                                          <C>           <C>        <C>          <C>
Quarter ended:
  September 30, 1999.......................  $1,004,437     33,834    1,077,262       .54
  December 31, 1999........................   1,044,398     55,942    1,096,213       .55
  March 31, 2000...........................   1,502,621     55,176    1,540,241       .77
  June 30, 2000............................     974,905     35,880    1,029,878       .51
                                             ----------    -------    ---------      ----
                                             $4,526,361    180,832    4,743,594      2.37
                                             ==========    =======    =========      ====
Quarter ended:
  September 30, 1998.......................  $  669,234     58,382      685,780       .34
  December 31, 1998........................     843,063     43,584      924,822       .46
  March 31, 1999...........................     648,852     39,260      747,857       .37
  June 30, 1999............................     679,405     34,943      725,990       .37
                                             ----------    -------    ---------      ----
                                             $2,840,554    176,169    3,084,449      1.54
                                             ==========    =======    =========      ====
</TABLE>

                                       19
<PAGE>   22
                     MARINE PETROLEUM TRUST AND SUBSIDIARY

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
                        THREE YEARS ENDED JUNE 30, 2000

(5) SUPPLEMENTAL INFORMATION RELATING TO OIL AND GAS RESERVES (UNAUDITED)

     Oil and gas reserve information relating to Marine's and Tidelands' royalty
interests is not presented because such information is not available to Marine
or Tidelands. Marine's share of oil and gas produced for its royalty interests
and the Marine's equity in oil and gas produced for Tidelands' royalty interests
were as follows:

<TABLE>
<CAPTION>
                                                            2000      1999      1998
                                                           -------   -------   -------
<S>                                                        <C>       <C>       <C>
Marine:
  Oil (barrels)..........................................   92,837    57,575    59,343
                                                           =======   =======   =======
  Gas (mcf)..............................................  807,837   869,636   582,594
                                                           =======   =======   =======
Tidelands:
  Oil (barrels)..........................................    3,527     4,163     3,245
                                                           =======   =======   =======
  Gas (mcf)..............................................   76,081   129,413   171,549
                                                           =======   =======   =======
</TABLE>

                                       20
<PAGE>   23

                                   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.

                                            MARINE PETROLEUM TRUST
                                              (Registrant)

                                            By: BANK OF AMERICA, N.A.
                                              in its capacity as trustee of
                                              Marine Petroleum Trust and not in
                                              its individual capacity or
                                              otherwise

                                            By:   /s/ CINDY STOVER MILLER
                                              ----------------------------------
                                                     Cindy Stover Miller
                                                        Vice President

Date: September 27, 2000

     Pursuant to the requirements of the Securities Exchange Act of 1934, this
report has been signed below by the following persons on behalf of the
registrant and in the capacities and on the dates indicated.

                                            BANK OF AMERICA, N.A.
                                              in its capacity as trustee of
                                              Marine Petroleum Trust and not in
                                              its individual capacity or
                                              otherwise

                                            By:   /s/ CINDY STOVER MILLER
                                              ----------------------------------
                                                     Cindy Stover Miller
                                                        Vice President

Date: September 27, 2000

                                                     /s/ R. RAY BELL
                                            ------------------------------------
                                                        R. Ray Bell
                                               (Principal Accounting Officer)

Date: September 27, 2000

                                       21
<PAGE>   24

                               INDEX TO EXHIBITS

<TABLE>
<CAPTION>
        EXHIBITS                                 DESCRIPTION
        --------                                 -----------
<S>                      <C>
           3.1           -- Indenture, as amended, of Marine, filed as Exhibit 3 to
                            the Annual Report on Form 10-K of Marine Petroleum Trust
                            for the fiscal year ended June 30, 1994, filed with the
                            Securities and Exchange Commission and incorporated by
                            reference herein.
           4.1           -- Form of Certificate evidencing Unit(s) of Beneficial
                            Interest, filed as Exhibit 4 to the Annual Report on Form
                            10-K of Marine Petroleum Trust for the fiscal year ended
                            June 30, 1994, filed with the Securities and Exchange
                            Commission and incorporated by reference herein.
          21.1           -- Subsidiaries of Marine.
          27.1           -- Financial Data Schedule.
</TABLE>