<PAGE>   1



                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549



                                    Form 10-Q



                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934



                  For the Quarterly Period Ended June 30, 2000


                           Commission File No. 1-8032



                          SAN JUAN BASIN ROYALTY TRUST


Texas                                                      I.R.S. No. 75-6279898


                     Bank One, Texas, N.A., Trust Department
                                 P. O. Box 2604
                             Fort Worth, Texas 76113

                          Telephone Number 817/884-4630



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
                                      ---   ---

Number of units of beneficial interest outstanding at July 31, 2000: 46,608,796

<PAGE>   2


                          SAN JUAN BASIN ROYALTY TRUST

                         PART I - FINANCIAL INFORMATION


Item 1.  Financial Statements.

The condensed financial statements included herein have been prepared by Bank
One, Texas, N.A. as Trustee for the San Juan Basin Royalty Trust (the "Trust"),
without audit, pursuant to the rules and regulations of the Securities and
Exchange Commission. Certain information and footnote disclosures normally
included in annual financial statements have been condensed or omitted pursuant
to Rule 10-01 of Regulation S-X promulgated under the Securities and Exchange
Act of 1934, although the Trustee believes that the disclosures are adequate to
make the information presented not misleading. These condensed financial
statements should be read in conjunction with the financial statements and the
notes thereto included in the Trust's annual report on Form 10-K for the year
ended December 31, 1999. In the opinion of the Trustee, all adjustments,
consisting only of normal recurring adjustments, necessary to present fairly the
assets, liabilities and trust corpus of the San Juan Basin Royalty Trust at June
30, 2000, and the distributable income and changes in trust corpus for the
three-month and six-month periods ended June 30, 2000 and 1999 have been
included. The distributable income for such interim periods is not necessarily
indicative of the distributable income for the full year.

Deloitte & Touche LLP, independent certified public accountants, has made a
limited review of the condensed financial statements as of June 30, 2000 and for
the three-month and six-month periods ended June 30, 2000 and 1999 included
herein.


                                      -2-
<PAGE>   3


INDEPENDENT ACCOUNTANTS' REPORT


Bank One, Texas, N.A. as Trustee
   for the San Juan Basin Royalty Trust:

We have reviewed the accompanying condensed statement of assets, liabilities and
trust corpus of the San Juan Basin Royalty Trust as of June 30, 2000 and the
related condensed statements of distributable income and changes in trust corpus
for the three-month and six-month periods ended June 30, 2000 and 1999. These
financial statements are the responsibility of the Trustee.

We conducted our reviews in accordance with standards established by the
American Institute of Certified Public Accountants. A review of interim
financial information consists principally of applying analytical procedures to
financial data and making inquiries of persons responsible for financial and
accounting matters. It is substantially less in scope than an audit conducted in
accordance with generally accepted auditing standards, the objective of which is
the expression of an opinion regarding the financial statements taken as a
whole. Accordingly, we do not express such an opinion.

The accompanying condensed financial statements are prepared on a modified cash
basis as described in Note 1, which is a comprehensive basis of accounting other
than generally accepted accounting principles.

Based on our reviews, we are not aware of any material modifications that should
be made to such condensed financial statements for them to be in conformity with
the basis of accounting described in Note 1.

We have previously audited, in accordance with generally accepted auditing
standards, the statement of assets, liabilities and trust corpus of the San Juan
Basin Royalty Trust as of December 31, 1999, and the related statements of
distributable income and changes in trust corpus for the year then ended (not
presented herein); and in our report dated March 24, 2000, we expressed an
unqualified opinion on those financial statements. In our opinion, the
information set forth in the accompanying condensed statement of assets,
liabilities and trust corpus as of December 31, 1999 is fairly stated, in all
material respects, in relation to the statement of assets, liabilities and trust
corpus from which it has been derived.




DELOITTE & TOUCHE LLP

July 14, 2000


                                      -3-
<PAGE>   4


                         PART I - FINANCIAL INFORMATION

ITEM 1. FINANCIAL STATEMENTS

SAN JUAN BASIN ROYALTY TRUST

CONDENSED STATEMENTS OF ASSETS, LIABILITIES AND TRUST CORPUS
--------------------------------------------------------------------------------

<TABLE>
<CAPTION>
                                                              JUNE 30,      DECEMBER 31,
ASSETS                                                           2000           1999
                                                             (UNAUDITED)
<S>                                                          <C>            <C>
Cash and short-term investments                              $  7,705,657   $  3,862,453
Net overriding royalty interest in producing
   oil and gas properties (net of accumulated
   amortization of $90,266,881 and $88,089,329
   at June 30, 2000 and December 31, 1999, respectively)       43,008,647     45,186,199
                                                             ------------   ------------

                                                             $ 50,714,304   $ 49,048,652
                                                             ============   ============

LIABILITIES AND TRUST CORPUS

Distribution payable to Unit holders                         $  7,705,657   $  3,862,453
Commitments and contingencies
Trust corpus - 46,608,796 Units of beneficial
   interest authorized and outstanding                         43,008,647     45,186,199
                                                             ------------   ------------

                                                             $ 50,714,304   $ 49,048,652
                                                             ============   ============
</TABLE>

CONDENSED STATEMENTS OF DISTRIBUTABLE INCOME (UNAUDITED)
--------------------------------------------------------------------------------

<TABLE>
<CAPTION>
                                         THREE MONTHS ENDED              SIX MONTHS ENDED
                                               JUNE 30,                      JUNE 30,
                                     ---------------------------   ---------------------------
                                        2000           1999           2000           1999
<S>                                  <C>            <C>            <C>            <C>
Royalty income                       $ 13,608,946   $  5,359,825   $ 23,685,540   $ 12,405,031
Interest income                            17,107         16,103         41,602         29,729
Other                                                    892,496                       892,496
                                     ------------   ------------   ------------   ------------

                                       13,626,053      6,268,424     23,727,142     13,327,256

General and administrative
   expenditures                           433,233        324,515        645,819        591,464
                                     ------------   ------------   ------------   ------------

Distributable income                 $ 13,192,820   $  5,943,909   $ 23,081,323   $ 12,735,792
                                     ============   ============   ============   ============

Distributable income per Unit
   (46,608,796 Units)                $    .283054   $    .127528   $    .495214   $    .273249
                                     ============   ============   ============   ============
</TABLE>

The accompanying notes to condensed financial statements are an integral part of
these statements.


                                      -4-
<PAGE>   5


SAN JUAN BASIN ROYALTY TRUST

CONDENSED STATEMENTS OF CHANGES IN TRUST CORPUS (UNAUDITED)
--------------------------------------------------------------------------------


<TABLE>
<CAPTION>
                                         THREE MONTHS ENDED              SIX MONTHS ENDED
                                               JUNE 30,                      JUNE 30,
                                     ---------------------------   ---------------------------
                                        2000           1999           2000           1999
<S>                                  <C>            <C>            <C>            <C>
Trust corpus, beginning of period    $ 43,972,106   $ 49,714,087   $ 45,186,199   $ 51,088,020
Amortization of net overriding
   royalty interest                      (963,459)    (1,373,459)    (2,177,552)    (2,747,392)
Distributable income                   13,192,820      5,943,909     23,081,323     12,735,792
Distributions declared                (13,192,820)    (5,943,909)   (23,081,323)   (12,735,792)
                                     ------------   ------------   ------------   ------------

Trust corpus, end of period          $ 43,008,647   $ 48,340,628   $ 43,008,647   $ 48,340,628
                                     ============   ============   ============   ============
</TABLE>


The accompanying notes to condensed financial statements are an integral part of
these statements.


                                      -5-
<PAGE>   6


SAN JUAN BASIN ROYALTY TRUST

NOTES TO CONDENSED FINANCIAL STATEMENTS (UNAUDITED)
--------------------------------------------------------------------------------


1.    BASIS OF ACCOUNTING

      The San Juan Basin Royalty Trust ("Trust") was established as of November
      1, 1980. The financial statements of the Trust are prepared on the
      following basis:

      o    Royalty income recorded for a month is the amount computed and paid
           by the working interest owner, Burlington Resources Oil & Gas Company
           ("BROG"), to the Trustee for the Trust. Royalty income consists of
           the amounts received by the owner of the interest burdened by the net
           overriding royalty interest ("Royalty") from the sale of production
           less accrued production costs, development and drilling costs,
           applicable taxes, operating charges, and other costs and deductions,
           multiplied by 75%. The Royalty income amount of $5,359,825 for the
           quarter ended June 30, 1999, does not include the $892,496 paid to
           the Trust for a one-time business interruption insurance claim.

      o    Trust expenses recorded are based on liabilities paid and cash
           reserves established from royalty income for liabilities and
           contingencies.

      o    Distributions to Unit holders are recorded when declared by the
           Trustee.

      o    The conveyance which transferred the overriding royalty interest to
           the Trust provides that any excess of production costs over gross
           proceeds must be recovered from future net profits.

      The financial statements of the Trust differ from financial statements
      prepared in accordance with generally accepted accounting principles
      ("GAAP") because revenues are not accrued in the month of production;
      certain cash reserves may be established for contingencies which would not
      be accrued in financial statements prepared in accordance with GAAP; and
      amortization of the Royalty calculated on a unit-of-production basis is
      charged directly to trust corpus.

2.    FEDERAL INCOME TAXES

      For federal income tax purposes, the Trust constitutes a fixed investment
      trust which is taxed as a grantor trust. A grantor trust is not subject to
      tax at the trust level. The Unit holders are considered to own the Trust's
      income and principal as though no trust were in existence. The income of
      the Trust is deemed to have been received or accrued by each Unit holder
      at the time such income is received or accrued by the Trust rather than
      when distributed by the Trust.

      The Royalty constitutes an "economic interest" in oil and gas properties
      for federal income tax purposes. Unit holders must report their share of
      the revenues of the Trust as ordinary income from oil and gas royalties
      and are entitled to claim depletion with respect to such income. The
      Royalty is treated as a single property for depletion purposes.

      The Trust has on file technical advice memoranda confirming the tax
      treatment described above.

      The Trust began receiving royalty income from coal seam gas wells
      beginning in 1989. Under Section 29 of the Internal Revenue Code, coal
      seam gas production from wells drilled prior to January 1, 1993 (including
      certain wells recompleted in coal seams formations thereafter), generally
      qualifies for the federal income tax credit for producing non-conventional
      fuels if such production and the sale thereof occurs before January 1,
      2003. For 1999, this tax credit was $1.04 per MMBtu. To benefit from the
      credit, each Unit holder must determine from the tax information they
      receive from the Trust, their pro rata share of qualifying production of
      the Trust, based upon the number of Units owned during each month of the
      year, and the amount of available credit per MMbtu for the year, and then
      apply the tax


                                      -6-
<PAGE>   7


      credit against their own income tax liability, but such credit may not
      reduce their regular tax liability (after the foreign tax credit and
      certain other nonrefundable credits) below their tentative minimum tax.
      Section 29 also provides that any amount of Section 29 credit disallowed
      for the tax year solely because of this limitation will increase their
      credit for prior year minimum tax liability, which may be carried forward
      indefinitely as a credit against the taxpayer's regular tax liability,
      subject, however, to the limitations described in the preceding sentence.
      There is no provision for the carryback or carryforward of the Section 29
      credit in any other circumstances.

      The Trustee is provided summary Section 29 tax credit information related
      to Trust properties by BROG, which information is then passed along to the
      Unit holders. In Nielson-True Partnership, et al, v. Commissioner, a 1997
      Tax Court decision, the court ruled that nonconventional fuel (such as
      coal seam gas) produced from a well drilled and completed in an otherwise
      qualifying formation prior to December 31, 1992, is not eligible for the
      Section 29 credit unless the producer has received an appropriate well
      category determination from the Federal Energy Regulatory Commission
      ("FERC"). On March 23, 1999, the U. S. Court of Appeals for the 10th
      Circuit affirmed that decision. Dictum (i.e., language in the appeals
      court's decision which is not binding as precedent) even suggests that,
      contrary to the clear implications of a 1993 Internal Revenue Service
      ruling, lack of such a well category determination may render the Section
      29 credit unavailable in respect of production from wells recompleted in a
      qualified formation after January 1, 1993, the date that FERC's authority
      to render well category determinations ended (so that obtaining the
      requisite determination for any such well was impossible). Many producers
      assert that wells meeting the definitional requirements applied by FERC in
      rendering well category determinations are eligible for the Section 29
      credit regardless of whether a well category determination is actually
      applied for or received, particularly for wells recompleted in qualifying
      formations after January 1, 1993, and additional litigation (and perhaps a
      legislative initiative) on this issue is to be expected. In fact, on
      December 23, 1999, a petition was filed with the FERC by a coalition of
      energy producers seeking reinstatement of the certification process. By
      letter dated January 14, 2000, the U. S. Department of Energy expressed
      its support of that petition. On July 14, 2000, the FERC issued a final
      ruling amending its regulations to reinstate certain regulations involving
      well category determinations for all wells and tight formation areas that
      could qualify for the Section 29 tax credit. The Trustee is in
      communication with BROG regarding the application of the amended
      regulations, BROG's plans, if any, to seek certification of additional
      wells and an assessment of the effects of the amended regulations on the
      Trust and its Unit holders. Pending such assessment and further
      developments, the availability of Section 29 tax credits to Unit holders
      with respect to some portion of the Trust's coal seam gas production could
      remain subject to debate and challenge.

      The classification of the Trust's income for purposes of the passive loss
      rules may be important to a Unit holder. As a result of the Tax Reform Act
      of 1986, royalty income will generally be treated as portfolio income and
      will not reduce passive losses.

3.    CONTINGENCIES

      See Part II - Item 1 Legal Proceedings concerning the status of litigation
      matters.

4.    UNDERCHARGE OF CAPITAL EXPENDITURES AND LEASE OPERATING EXPENSES

      Based on its year-end review, BROG has determined that since January of
      1999, BROG has undercharged the Trust for both capital expenditures and
      lease operating charges related to properties burdened by the Trust but
      not operated by BROG. In April and May of 2000, BROG passed through to the
      Trust additional charges of $652,303 in capital expenditures and
      $1,689,509 in lease operating charges related to the undercharged
      non-operated properties. The Trust's consultants will continue their
      review of cost reporting data and advise the Trust as to the
      appropriateness of the pass through of these additional charges.


                                      -7-
<PAGE>   8


5.    SETTLEMENT OF CLAIMS RELATING TO GAS IMBALANCE

      In June 2000, the Trust and BROG entered into a partial settlement of
      claims relating to a gas imbalance with respect to production from mineral
      properties currently operated by BROG. Under the terms of the partial
      settlement, BROG paid the Trust $3,490,000 to settle the imbalance insofar
      as it relates to some of the wells located on the subject properties. The
      remainder of the imbalance is to be addressed through volume adjustments
      whereby the Trust's net overriding royalty interest will be applied to 50%
      of the overproduced parties' interest, on a monthly basis, until the
      imbalance is corrected. The Trust is in communication with BROG in order
      to determine the estimated value of the volume adjustments and the time
      during which the remainder of the imbalance will be corrected.

                                     ******


                                      -8-
<PAGE>   9


ITEM 2.   TRUSTEE'S DISCUSSION AND ANALYSIS

FORWARD LOOKING INFORMATION

Certain information included in this report contains, and other materials filed
or to be filed by the Trust with the Securities and Exchange Commission (as well
as information included in oral statements or other written statements made or
to be made by the Trust) may contain or include, forward-looking statements
within the meaning of Section 21E of the Securities Exchange Act of 1934, and
Section 27A of the Securities Act of 1933. Such forward looking statements may
be or may concern, among other things, capital expenditures, drilling activity,
development activities, production efforts and volumes, hydrocarbon prices and
the results thereof, and regulatory matters. Such forward looking statements
generally are accompanied by words such as "may," "will," "estimate," "expect,"
"predict," "anticipate," "goal," "should," "assume," "believe," "plan,"
"intend," or other words that convey the uncertainty of future events or
outcomes. Such statements reflect our current view with respect to future
events; are based on our assessment of, and are subject to, a variety of factors
deemed relevant by the Trustee and involve risks and uncertainties. Should one
or more of these risks or uncertainties occur, actual results may vary
materially and adversely from those anticipated.


                                      -9-
<PAGE>   10


THREE MONTHS ENDED JUNE 30, 2000 AND JUNE 30, 1999:

The Trust received royalty income of $13,608,946 and interest income of $17,107
during the second quarter of 2000. The royalty income amount of $13,608,946 for
the quarter ended June 30, 2000, includes $3,490,000 paid to the Trust as
partial settlement of its claims relating to a gas imbalance with respect to
production from mineral properties currently operated by BROG. After deducting
administrative expenses of $433,233 distributable income for the quarter was
$13,192,820 ($.283054 per Unit). In the second quarter of 1999, royalty income
was $5,359,825 and interest income was $16,103. The royalty income amount of
$5,359,825 for the quarter ended June 30, 1999, does not include the $892,496
paid to the Trust for a one-time business interruption insurance claim. After
deducting administrative expenses of $324,515, distributable income for the
quarter was $5,943,909 ($.127528 per Unit). The tax credit relating to
production from coal seam wells totaled approximately $.04 per Unit for the
second quarter of 2000 and $.03 per Unit for the second quarter of 1999. For
further information concerning this tax credit, Unit holders should refer to the
Trust's Annual Report for 1999. Based on 46,608,796 Units outstanding, the per
Unit distributions during the second quarter of 2000 were as follows:

<TABLE>
<S>                                           <C>
     April                                    $ .067251
     May                                        .050477
     June                                       .165326
                                              ---------
     Quarter Total                            $ .283054
                                              =========
</TABLE>


The royalty income distributed in the second quarter of 2000 was higher than
that distributed in the second quarter of 1999, primarily due to an increase in
the average gas price from $1.34 per Mcf for the second quarter of 1999 to $2.39
per Mcf for the second quarter of 2000, and the gas imbalance claims settlement
of $3,490,000 received during the second quarter of 2000. Interest earnings for
the quarter ended June 30, 2000, as compared to the quarter ended June 30, 1999,
were higher, primarily due to an increase in funds available for investment.
Administrative expenses were higher, primarily as a result of differences in
timing of the receipt and payment of these expenses.

The capital costs attributable to the properties from which the Trust's 75% net
overriding royalty ("Royalty") was carved (the "Underlying Properties") for the
second quarter of 2000 were reported by BROG as $4,779,093 (including $652,000
relating to undercharges during prior periods on non-operated properties) versus
$2,997,840 for the second quarter of 1999. BROG has reduced its estimate for
capital expenditures for 2000 from $20,500,000 to $18,500,000, of which
$9,400,000 has been incurred through June 30, 2000. BROG has indicated to the
Trust that it anticipates the benefit of the higher capital spending will be
realized in the form of a near offset of the natural production decline for
calendar year 2000, and that full realization of this benefit should be seen by
year-end.

In April 2000, BROG informed the Trustee that it had determined that since
January of 1999, BROG had undercharged the Trust for both capital expenditures
and lease operating charges related to properties burdened by the Trust's
Royalty but not operated by BROG. In April and May of 2000, BROG passed through
to the Trust additional charges of $652,303 in capital expenditures and
$1,689,509 in lease operating charges related to the undercharged non-operated
properties.

Lease operating expenses and property taxes increased to $5,028,808 for the
second quarter of 2000 as compared to $2,849,124 for the second quarter of 1999
primarily due to the passed through lease operating charges related to
undercharged non-operated properties.


                                      -10-
<PAGE>   11


BROG has informed the Trustee that during the second quarter of 2000, seven
gross (2.57 net) conventional wells and five gross (2.55 net) conventional
recompletions were completed on the Underlying Properties. There were 92 gross
(29.78 net) conventional wells and 33 gross (5.43 net) recompletions in progress
at June 30, 2000. Six gross (.04 net) coal seam recavitations and two gross (.08
net) coal seam recompletions were completed in the second quarter of 2000. Ten
gross (4.54 net) coal seam wells, eleven gross (.07 net) coal seam recavitations
and five gross (1.35 net) coal seam recompletions were in progress at June 30,
2000. By comparison, 17 gross (.30 net) conventional wells were completed on the
Underlying Properties during the second quarter of 1999. There were 66 gross
(14.28 net) conventional wells and eight gross (1.45 net) recompletions in
progress at June 30, 1999. Seven gross (.048 net) coal seam recavitations were
completed and 14 gross (.27 net) coal seam recavitations were in progress in the
second quarter of 1999. Three gross (1.42 net) coal seam wells and one gross
(.108 net) coal seam recompletion were in progress at June 30, 1999.

Royalty income for the quarter ended June 30, 2000 is associated with actual gas
and oil production during February 2000 through April 2000 from the Underlying
Properties. Gas and oil sales from the Underlying Properties for the quarters
ended June 30, 2000 and 1999 were as follows:

<TABLE>
<CAPTION>
                                                  2000            1999
<S>                                            <C>             <C>
Gas:
    Total sales (Mcf)                           10,662,060     10,533,677
    Mcf per day                                    118,467        118,356
    Average price (per Mcf)                    $      2.39    $      1.34

Oil:
    Total sales (Bbls)                              21,777         18,074
    Bbls per day                                       242            203
    Average price (per Bbl)                    $     21.66    $     12.65
</TABLE>

Gas and oil sales attributable to the Royalty for the quarters ended June 30,
2000 and 1999 were as follows:


<TABLE>
<CAPTION>
                                                   2000           1999
<S>                                             <C>             <C>
Gas sales (Mcf)                                  4,567,487      4,393,718
Oil sales (Bbls)                                     9,473          7,598
</TABLE>

During the second quarter of 2000, gas prices were higher than during the second
quarter of 1999. Gas production increased slightly in 2000 as compared to 1999.
The price per barrel of oil during the second quarter of 2000 was $9.01 per bbl
higher than that received for the second quarter of 1999 due to increases in oil
prices in world markets generally including the posted prices applicable to oil
sales attributable to the Royalty.

Since the oil and gas sales attributable to the Royalty are based on an
allocation formula that is dependent on such factors as price and cost,
including capital expenditures, the aggregate production volumes from the
Underlying Properties may not provide a meaningful comparison to volumes
attributable to the Royalty.

BROG has entered into a contract dated November 10, 1999, for the sale of all
volumes of gas which are subject to the Royalty (the "Trust gas") to Duke Energy
and Marketing L.L.C. That contract provides for the delivery of Trust gas at
various delivery points over a period commencing January 1, 2000, and ending
October 31, 2001, and provides for the sale of Trust gas at prices which
fluctuate in accordance with published indices for gas sold in the San Juan
Basin of New Mexico. Unit holders are referred to Note 6 of


                                      -11-
<PAGE>   12


the Notes to Financial Statements in the Trust's 1999 Annual Report for further
information concerning the marketing of gas produced from the Underlying
Properties.

In February 1999, the Trust's consultants notified the Trust of an apparent gas
imbalance. A gas imbalance occurs where more than one party is entitled to the
economic benefit of the production of natural gas, but the gas is sold for the
account of less than all of the parties. The resulting imbalance may be
corrected by various means including a cash settlement and/or a volume
adjustment whereby an increased percentage of future production is sold for the
account of the underproduced party or parties. The Trust's consultants suggested
that the subject imbalance might relate to the acquisition by BROG's
predecessor, Southland Royalty Company ("Southland Royalty"), of mineral
properties which had been operated under a Joint Operating Agreement between
Southland Royalty and Unicon, the seller of the properties. The Trust made
inquiry of BROG concerning the imbalance and BROG agreed to investigate the
records. The Trustee met with BROG representatives in June 1999 to discuss the
investigation and by correspondence of September 24, 1999, BROG reported that
the imbalance probably related to problems experienced in the 1980's and early
1990's by Southland Royalty and Unicon in their dealings with Public Service
Company of New Mexico. BROG reported that Unicon was flowing gas to its account
while Southland Royalty was not producing and that this created a gas imbalance.
The imbalance was addressed, as between Southland Royalty and Unicon, by a
reduction in the total purchase price for Unicon assets acquired by Southland
Royalty in June 1990. However, there was no payment made to the Trust at the
time of that acquisition.

In June 2000, the Trust and BROG entered into a partial settlement of the claims
relating to the gas imbalance, under the terms of which BROG paid the Trust
$3,490,000 to settle the imbalance insofar as it relates to some of the wells
located on the subject properties. The remainder of the imbalance is to be
addressed through volume adjustments whereby the Trust's net overriding royalty
interest will be applied to 50% of the overproduced parties' interest, on a
monthly basis, until the imbalance is corrected. The Trust is in communication
with BROG in order to determine the estimated value of the volume adjustments
and the time during which the remainder of the imbalance will be corrected.

SIX MONTHS ENDED JUNE 30, 2000 AND 1999:

For the six months ended June 30, 2000 distributable income was $23,081,323
($.495214 per Unit) which was more than the $12,735,792 ($.273249 per Unit) of
income distributed during the same period in 1999. The increase resulted
primarily from increases in gas and oil prices. Interest income for the six
months ended June 30, 2000 was $41,602 compared to $29,729 during the first six
months of 1999. This increase is due to an increase in funds available for
investment. General and administrative expenses increased to $645,819 from
$591,464 during the 1999 period primarily due to differences in timing of the
receipt and payment of these expenses.

Capital expenditures incurred by BROG, attributable to the Underlying
Properties, for the first six months of 2000 amounted to $9,362,219. Capital
expenditures were $5,271,041 for the first six months of 1999. Lease operating
expenses and property taxes totaled $8,136,369 for the first six months of 2000
compared to $5,644,926 for the first six months of 1999. The six month 2000
amounts include the charges for non-operated properties by BROG mentioned above.

BROG informed the Trustee that during the six months ended June 30, 2000, 14
gross (5.98 net) conventional wells were completed on the Underlying Properties.
Eight gross (3.69 net) conventional wells were recompleted. Nineteen gross (.11
net) coal seam wells were recavitated and two gross (.08 net) coal seam
recompletions were completed during the first six months of 2000. During the six
months ended June 30, 1999, 22 gross (.401 net) conventional wells were
completed on the Underlying Properties. One gross (.65 net) conventional well
was recompleted. Twelve gross (.144 net) coal seam wells were recavitated during
the first six months of 1999.


                                      -12-
<PAGE>   13


Royalty income for the six months ended June 30, 2000 is associated with actual
gas and oil production during November 1999 through April 2000 from the
Underlying Properties. Gas and oil sales from the Underlying Properties for the
six months ended June 30, 2000 and 1999 were as follows:

<TABLE>
<CAPTION>
                                                  2000            1999
<S>                                           <C>              <C>
Gas:
   Total sales (Mcf)                           20,742,656       20,871,116
   Mcf per day                                    113,971          115,310
   Average price (per Mcf)                    $      2.31      $      1.44

Oil:
   Total sales (Bbls)                              45,067           36,520
   Bbls per day                                       248              202
   Average price (per Bbl)                    $     22.10      $     11.12
</TABLE>

Gas and oil sales attributable to the Royalty for the six months ended June 30,
2000 and 1999 were as follows:

<TABLE>
<CAPTION>
                                                 2000             1999
<S>                                            <C>              <C>

Gas sales (Mcf)                                9,310,784        9,436,600
Oil sales (Bbls)                                  20,577           16,616
</TABLE>

During the first six months of 2000, gas and oil prices were higher than during
the first six months of 1999. Since the oil and gas sales attributable to the
Royalty are based on an allocation formula that is dependent on such factors as
price and cost, including capital expenditures, the aggregate sales amounts from
the Underlying Properties may not provide a meaningful comparison to sales
attributable to the Royalty.


                                      -13-
<PAGE>   14


CALCULATION OF ROYALTY INCOME:

Royalty income received by the Trust for the three months and six months ended
June 30, 2000 and 1999, respectively, was computed as shown in the following
table:

<TABLE>
<CAPTION>
                                              THREE MONTHS ENDED              SIX MONTHS ENDED
                                                    JUNE 30,                       JUNE 30,
                                        ----------------------------     ----------------------------
                                            2000           1999             2000            1999
<S>                                     <C>             <C>              <C>             <C>
Gross proceeds of sales from the
   Underlying Properties:

   Gas proceeds                         $ 25,242,345    $ 14,138,802     $ 47,756,306    $ 30,090,028
   Oil proceeds                              483,594         228,556        1,009,004         406,116
                                        ------------    ------------     ------------    ------------

Total                                     25,725,939      14,367,358       48,765,310      30,496,144
                                        ------------    ------------     ------------    ------------

Less production costs:
   Severance tax - Gas                     2,266,118       1,448,732        4,460,637       3,097,060
   Severance tax - Oil                        38,382          20,674           90,422          38,522
   Lease operating expenses and
      property tax (a)                     5,028,808       2,849,124        8,136,369       5,644,926
   Capital expenditures (a)                4,779,093       2,997,840        9,362,219       5,271,041
   Other                                     121,610         (95,445)         121,610         (95,445)
                                        ------------    ------------     ------------    ------------

Total                                     12,234,011       7,220,925       22,171,257      13,956,104
                                        ------------    ------------     ------------    ------------

Net profits                               13,491,928       7,146,433       26,594,053      16,540,040
                                        ------------    ------------     ------------    ------------

Net overriding royalty interest                   75%             75%              75%             75%
                                        ------------    ------------     ------------    ------------

Subtotal                                  10,118,946       5,359,825       19,945,540      12,405,031
Other (b)                                  3,490,000                        3,740,000
                                        ------------    ------------     ------------    ------------

Royalty income                          $ 13,608,946    $  5,359,825     $ 23,685,540    $ 12,405,031
                                        ============    ============     ============    ============
</TABLE>


(a)  Includes charges received from BROG during the three months ended June 30,
     2000 for capital expenditures ($652,000) and lease operating costs
     ($1,690,000) relating to non-operated properties not previously charged to
     the Trust (see Note 4 to the financial statements).

(b)  Represents additional revenues of $3,490,000 received in the second quarter
     of 2000 as settlement of a gas imbalance and a $250,000 offset to lease
     operating expense in the first quarter of 2000 in connection with the
     settlement of litigation.

ITEM 3. QUALITATIVE AND QUANTITATIVE DISCLOSURES ABOUT MARKET RISK

The Trust has not entered into derivative financial instruments, derivative
commodity instruments or other similar instruments during the quarter ended June
30, 2000. The Trust does not market the Trust gas, oil and/or natural gas
liquids. BROG is responsible for such marketing.


                                      -14-
<PAGE>   15


                           PART II - OTHER INFORMATION

ITEM 1.   LEGAL PROCEEDINGS

          The Trust is not a party to any litigation. However, the Trust is
          aware that BROG is involved in litigation from time to time that could
          affect the royalty income received by the Trust.

          A lawsuit was commenced on September 1, 1995, against BROG by certain
          royalty and overriding royalty owners on behalf of those persons
          similarly situated. The suit involves properties that are burdened by
          the Trust. This case is one of six virtually identical class actions
          filed against New Mexico gas producers. All such cases have been
          consolidated in the First Judicial District of Santa Fe County, New
          Mexico where the case is styled San Juan 1990-A, L.P., et al. v. El
          Paso Production Company and Meridian Oil Inc. The plaintiffs allege
          that they and members of the proposed class have been underpaid for
          royalties and overriding royalties. The plaintiffs have sought to
          certify the actions as class actions and seek monetary damages. The
          court has denied class certification, but the plaintiffs have renewed
          their request for class certification. Discovery in this matter is
          closed. BROG anticipates summary judgment proceedings to occur in the
          fall of 2000. Because of the pending nature of the litigation,
          exposure to the Trust from this suit cannot be quantified. However, if
          the plaintiffs who have interests in properties that are burdened by
          the Trust are successful, royalty income received by the Trust could
          decrease.

          In addition, an administrative claim was initiated on March 17, 1997,
          by the Mineral Management Service of the United States Department of
          the Interior (the "MMS") against BROG regarding a gas contract
          settlement dated March 1, 1990, between BROG and certain other parties
          thereto. The claim alleges that additional royalties are due on
          production from federal and Indian leases in the State of New Mexico
          on properties that are burdened by the Royalty. BROG filed its
          statement of reasons in June 1997 thereby contesting whether the
          royalties are payable as claimed. BROG has informed the Trust that the
          administrative claim is in the appeal process. If the MMS claim is
          successful, royalty income received by the Trust could decrease. BROG
          reports that the MMS and BROG have entered into settlement discussions
          in an attempt to settle this issue together with other take-or-pay
          claims made by the MMS, but there has been no indication of the
          likelihood of success in resolving the claim or when the negotiations
          are to be completed.

          MMS has notified BROG of underpaid royalty related to coal seam gas
          including inappropriate deductions for costs to separate carbon
          dioxide from the gas. BROG has continued to calculate and pay
          royalties using deductions the MMS is attempting to disallow. The
          Company has appealed the MMS Demand Letter dated October 28, 1996.
          There is a tolling agreement with the MMS while settlement
          negotiations are attempted.

          BROG is in negotiations with the State of New Mexico for a tax refund
          based upon a claim for reimbursement of compression costs used in
          calculating wellhead values. BROG has obtained the approval of the
          Attorney General of New Mexico of a settlement in the amount of
          $4,200,000, and payment in that amount has been received. BROG has
          informed the Trust that its preliminary calculations indicate that the
          proportion of the settlement proceeds which will be attributable to
          the Trust is approximately $250,000.

ITEM 6.   EXHIBITS AND REPORTS ON FORM 8-K

          (a)  Exhibits

               (4)(a) San Juan Basin Royalty Trust Indenture dated November 3,
                      1980, between Southland Royalty Company (now Burlington
                      Resources Oil & Gas Company) and The Fort Worth National
                      Bank (now Bank One, Texas, N.A.), as Trustee,


                                      -15-
<PAGE>   16


                      heretofore filed as Exhibit (4)(a) to the Trust's Annual
                      Report on Form 10-K to the Securities and Exchange
                      Commission for the fiscal year ended December 31, 1980 is
                      incorporated herein by reference.

               (4)(b) Net Overriding Royalty Conveyance from Southland Royalty
                      Company (now Burlington Resources Oil & Gas Company) to
                      The Fort Worth National Bank (now Bank One, Texas, N.A.),
                      as Trustee, dated November 3, 1980 (without Schedules),
                      heretofore filed as Exhibit (4)(b) to the Trust's Annual
                      Report on Form 10-K to the Securities and Exchange
                      Commission for the fiscal year ended December 31, 1980 is
                      incorporated herein by reference.

               (27)   Financial Data Schedule

          (b)  Reports on Form 8-K

               The Trust filed a report on Form 8-K on June 30, 2000. In the
               report, the Trust reported, under Item 5, that it had announced
               the partial settlement of its claims relating to a gas imbalance
               with respect to production from mineral properties currently
               operated by BROG.


                                      -16-
<PAGE>   17


                                   SIGNATURES


Pursuant to the requirements 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.

                                       BANK ONE, TEXAS, N.A., AS TRUSTEE FOR
                                       THE SAN JUAN BASIN ROYALTY TRUST



                                             By  /s/ LEE ANN ANDERSON
                                                ----------------------------
                                                      Lee Ann Anderson
                                                        Vice President

Date:  August 14, 2000


               (The Trust has no directors or executive officers.)


                                      -17-
<PAGE>   18


                                INDEX TO EXHIBITS


<TABLE>
<CAPTION>
                                                                                                  SEQUENTIALLY
               EXHIBIT                                                                              NUMBERED
               NUMBER                                EXHIBIT                                          PAGE
<S>                       <C>                                                                     <C>
               (4)(a)     San Juan Basin Royalty Trust Indenture dated November
                          3, 1980, between Southland Royalty Company (now
                          Burlington Resources Oil & Gas Company) and The Fort
                          Worth National Bank (now Bank One, Texas, N.A.), as
                          Trustee, heretofore filed as Exhibit (4)(a) to the
                          Trust's Annual Report on Form 10 K to the Securities
                          and Exchange Commission for the fiscal year ended
                          December 31, 1980 is incorporated herein by
                          reference.*


               (4)(b)     Net Overriding Royalty Conveyance from Southland
                          Royalty Company (now Burlington Resources Oil & Gas
                          Company) to The Fort Worth National Bank (now Bank
                          One, Texas, N.A.), as Trustee, dated November 3, 1980
                          (without Schedules), heretofore filed as Exhibit
                          (4)(b) to the Trust's Annual Report on Form 10-K to
                          the Securities and Exchange Commission for the fiscal
                          year ended December 31, 1980 is incorporated herein by
                          reference.*

               (27)       Financial Data Schedule **
</TABLE>


*    A copy of this Exhibit is available to any Unit holder, at the actual cost
     of reproduction, upon written request to the Trustee, Bank One, Texas,
     N.A., P.O. Box 2604, Fort Worth, Texas 76113.

**   Filed herewith.