<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 September 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 October 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
September 30, 2000, and the distributable income and changes in trust corpus for
the three-month and nine-month periods ended September 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 conducted a
limited review of the condensed financial statements as of September 30, 2000
and for the three-month and nine-month periods ended September 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 September 30, 2000 and
the related condensed statements of distributable income and changes in trust
corpus for the three-month and nine-month periods ended September 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 auditing standards generally
accepted in the United States of America, 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

October 27, 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>
                                                                 SEPTEMBER 30,    DECEMBER 31,
ASSETS                                                               2000             1999
                                                                  (UNAUDITED)
<S>                                                             <C>              <C>
Cash and short-term investments                                 $    7,391,680   $    3,862,453
Net overriding royalty interest in producing
   oil and gas properties (net of accumulated
   amortization of $91,616,394 and $88,089,329
   at September 30, 2000 and December 31, 1999, respectively)       41,659,134       45,186,199
                                                                --------------   --------------

                                                                $   49,050,814   $   49,048,652
                                                                ==============   ==============

LIABILITIES AND TRUST CORPUS

Distribution payable to Unit holders                            $    7,391,680   $    3,862,453
Commitments and contingencies
Trust corpus - 46,608,796 Units of beneficial
   interest authorized and outstanding                              41,659,134       45,186,199
                                                                --------------   --------------

                                                                $   49,050,814   $   49,048,652
                                                                ==============   ==============
</TABLE>

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

<TABLE>
<CAPTION>
                                    THREE MONTHS ENDED             NINE MONTHS ENDED
                                       SEPTEMBER 30,                 SEPTEMBER 30,
                                ---------------------------   ---------------------------
                                    2000           1999           2000           1999
<S>                             <C>            <C>            <C>            <C>
Royalty income                  $ 19,747,200   $  7,908,631   $ 43,432,740   $ 20,313,662
Interest income                       60,985         13,147        102,587         42,876
Other                                                                             892,496
                                ------------   ------------   ------------   ------------
                                  19,808,185      7,921,778     43,535,327     21,249,034

General and administrative
   expenditures                      156,718        156,248        802,537        747,712
                                ------------   ------------   ------------   ------------

Distributable income            $ 19,651,467   $  7,765,530   $ 42,732,790   $ 20,501,322
                                ============   ============   ============   ============

Distributable income per Unit
   (46,608,796 Units)           $    .421626   $    .166611   $    .916840   $    .439860
                                ============   ============   ============   ============
</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              NINE MONTHS ENDED
                                            SEPTEMBER 30,                  SEPTEMBER 30,
                                    ----------------------------    ----------------------------
                                        2000            1999            2000            1999
                                    ------------    ------------    ------------    ------------
<S>                                 <C>             <C>             <C>             <C>
Trust corpus, beginning of period   $ 43,008,647    $ 48,340,628    $ 45,186,199    $ 51,088,020
Amortization of net overriding
   royalty interest                   (1,349,513)     (1,474,591)     (3,527,065)     (4,221,983)
Distributable income                  19,651,467       7,765,530      42,732,790      20,501,322
Distributions declared               (19,651,467)     (7,765,530)    (42,732,790)    (20,501,322)
                                    ------------    ------------    ------------    ------------

Trust corpus, end of period         $ 41,659,134    $ 46,866,037    $ 41,659,134    $ 46,866,037
                                    ============    ============    ============    ============
</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 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 $20,313,662 for the
           nine months ended September 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



                                      -6-
<PAGE>   7

      month of the year, and the amount of available credit per MMbtu for the
      year, and then apply the tax 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). However, 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. BROG has informed the Trustee that it will seek certification
      of all qualified wells. Pending such certification and further
      developments, the availability of Section 29 tax credits to Unit holders
      with respect to a minor 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 have reviewed BROG's cost
      reporting data and confirmed that the pass through of these additional
      charges is appropriate.

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



                                      -7-
<PAGE>   8

      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. The volume adjustment
      commenced in August 2000 and will be monitored by the Trust's consultants.

                                     ******



                                      -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 SEPTEMBER 30, 2000 AND 1999:

The Trust received royalty income of $19,747,200 and interest income of $60,985
during the third quarter of 2000. After deducting administrative expenses of
$156,718, distributable income for the quarter was $19,651,467 ($.421626 per
Unit). In the third quarter of 1999, royalty income was $7,908,631, interest
income was $13,147, administrative expenses were $156,248 and distributable
income was $7,765,530 ($.166611 per Unit). The tax credit relating to production
from coal seam wells totaled approximately $.05 per Unit for the third quarter
of 2000 and $.04 per Unit for the third 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 third quarter of 2000 were as follows:

<TABLE>
<S>             <C>
July            $.122778
August           .140258
September        .158590
                --------

Quarter Total   $.421626
                ========
</TABLE>

The royalty income distributed in the third quarter of 2000 was higher than that
distributed in the third quarter of 1999, due to an increase in the average gas
price from $1.84 per Mcf for the third quarter of 1999 to $3.39 per Mcf for the
third quarter of 2000 as well as increased production levels of both gas and
oil, and an increase in the average oil price from $15.69 per barrel for the
third quarter of 1999 to $25.58 for the third quarter of 2000. Interest earnings
for the quarter ended September 30, 2000, as compared to the quarter ended
September 30, 1999, were higher, primarily due to an increase in funds available
for investment. Administrative expenses were approximately the same in the third
quarter of 2000 as compared to the same period in 1999.

The capital costs attributable to the properties from which the Trust's 75% net
overriding royalty ("Royalty") was carved (the "Underlying Properties") for the
third quarter of 2000 were reported by BROG as $4,994,236 versus $2,720,024 for
the third quarter of 1999. BROG has recently informed the Trustee that its
estimated capital budget for the Underlying Properties for 2000 has been
increased from $18,500,000 to $24,500,000. Approximately $14,400,000 of capital
expenses have been incurred through September 30, 2000, but BROG indicates that
approximately $5,000,000 of that amount related to BROG's 1999 capital budget
for the Underlying Properties such that approximately $15,100,000 of the 2000
capital budget remains to be spent either this calendar year or thereafter. The
projected increase is to cover the costs of (a) the drilling of six new wells on
portions of the Underlying Properties not operated by Burlington; (b) multiple
completions to the Dakota and Pictured Cliffs formations in wells heretofore
budgeted for completion only to the Mesaverde formation; and (c) additional
tubing and other facilities at existing wells, as required to maintain
production in the face of an increase in pressure on the gathering system
operated by Williams Field Services on which gas produced from those wells is
transported.

Lease operating expenses and property taxes increased to $3,153,169 for the
third quarter of 2000 as compared to $2,243,776 for the third quarter of 1999.
In 1999, BROG accrued $493,473 for January 1999 lease operating expenses
mistakenly thought not to have been processed. This accrual was reversed in
August 1999 when it was determined that the majority of such charges had in fact
been processed. This reversal of charges has caused lease operating expenses for
the third quarter of 1999 to appear more dramatically lower than for the same
period of 2000.

BROG has informed the Trustee that during the third quarter of 2000, twelve
gross (8.36 net) conventional wells and one gross (0.003 net) conventional
recompletion were completed on the Underlying Properties. There were 103 gross
(26.24 net) conventional wells and 32 gross (5.43 net) conventional
recompletions in



                                      -10-
<PAGE>   11

progress at September 30, 2000. Four gross (2.84 net) coal seam wells and six
gross (0.04 net) coal seam recavitations were completed in the third quarter of
2000. Fourteen gross (4.70 net) coal seam wells, eight gross (0.04 net) coal
seam recavitations and ten gross (1.57 net) coal seam recompletions were in
progress at September 30, 2000. By comparison, there were 49 gross (11.81 net)
conventional wells in progress as of September 30, 1999, and there was one gross
(0.05 net) coal seam well completed on the Underlying Properties during the
third quarter of 1999. One gross (0.88 net) coal seam well, 19 gross (0.28 net)
coal seam recavitations and five gross (1.22 net) coal seam recompletions were
in progress as of September 30, 1999. "Gross" acres or wells, for purposes of
this discussion, means the entire ownership interest of all parties in such
properties, and BROG's interest therein is referred to as the "net" acres or
wells.

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

<TABLE>
<CAPTION>
                                 2000         1999
<S>                           <C>          <C>
Gas:
    Total sales (Mcf)         11,190,629    9,253,207
    Mcf per day                  121,637      100,578
    Average price (per Mcf)   $     3.39   $     1.84

Oil:
    Total sales (Bbls)            27,858       18,837
    Bbls per day                     303          205
    Average price (per Bbl)   $    25.58   $    15.69
</TABLE>

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

<TABLE>
<CAPTION>
                      2000         1999
<S>                 <C>          <C>
Gas sales (Mcf)     6,397,659    4,717,239
Oil sales (Bbls)       15,909        9,480
</TABLE>

During the third quarter of 2000, gas prices were significantly higher than
during the third quarter of 1999. Gas production also increased in 2000 as
compared to 1999. The price per barrel of oil during the third quarter of 2000
was $9.89 per barrel higher than that received for the third 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.

Gas sales attributable to the Royalty increased in the third quarter of 2000, as
compared to the same period in 1999. All volumes of gas which are subject to the
Royalty (the "Trust gas") are currently sold under a contract dated November 10,
1999 between BROG and 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 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.



                                      -11-
<PAGE>   12

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.

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 volume adjustment commenced
in August 2000 and will be monitored by the Trust's consultants.

NINE MONTHS ENDED SEPTEMBER 30, 2000 AND 1999:

For the nine months ended September 30, 2000 distributable income was
$42,732,790 ($.916840 per Unit) which was greater than the $20,501,322 ($.439860
per Unit) of income distributed during the same period in 1999. The increase in
distributable income resulted primarily from increases in gas and oil prices.
The royalty income amount of $43,432,740 for the nine months ended September 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. The royalty income amount of $20,313,662 for the
nine months ended September 30, 1999, does not include the $892,496 paid to the
Trust for a one-time business interruption insurance claim. Interest income for
the nine months ended September 30, 2000 was $102,587 compared to $42,876 during
the first nine months of 1999. This increase is due to an increase in funds
available for investment. General and administrative expenses increased to
$802,537 from $747,712 during the 1999 period primarily due to differences in
timing of the receipt and payment of these expenses.

Reports received from BROG in 1999 indicated lower production for the months of
June and July 1999, as compared to the prior year. Upon inquiry from the Trust,
BROG responded that the apparent declines in gas production for those months did
not reflect actual declines in gas productivity, but rather, were the result of
prior period adjustments. BROG indicated that deficiencies in its new internal
accounting system precluded it from generating actual production reports for the
months of January through August, and it instead relied upon estimates based on
historical production, which estimates proved high. The prior period adjustments
were employed by BROG to reconcile the difference between its estimates and the
actual production for the



                                      -12-
<PAGE>   13

subject months. The Trust's consultants have reviewed data supplied by BROG in
support of the prior period adjustments and have preliminarily approved them,
subject to final audit.

Capital expenditures incurred by BROG, attributable to the Underlying
Properties, for the first nine months of 2000 amounted to $14,356,455. Capital
expenditures were $7,991,065 for the first nine months of 1999. Lease operating
expenses and property taxes totaled $11,289,538 for the first nine months of
2000 compared to $7,888,702 for the first nine months of 1999.

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.

BROG advised the Trustee that during the nine months ended September 30, 2000,
26 gross (14.34 net) conventional wells were completed on the Underlying
Properties, and nine gross (3.693 net) conventional wells were recompleted. Four
gross (2.84 net) coal seam wells were completed. Twenty-five gross (0.15 net)
coal seam wells were recavitated and two gross (0.08 net) coal seam wells were
recompleted during the first nine months of 2000. During the nine months ended
September 30, 1999, 22 gross (.401 net) conventional gas wells were completed on
the Underlying Properties and one gross (.05 net) coal seam well was completed.
Twelve gross (.144 net) coal seam wells were recavitated during the first nine
months of 1999.

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

<TABLE>
<CAPTION>
                                 2000           1999
<S>                          <C>            <C>
Gas:
   Total sales (Mcf)           31,933,285     30,124,323
   Mcf per day                    116,545        110,346
   Average price (per Mcf)   $       2.75   $       1.56

Oil:
   Total sales (Bbls)              72,925         55,357
   Bbls per day                       266            203
   Average price (per Bbl)   $      23.62   $      12.69
</TABLE>

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

<TABLE>
<CAPTION>
                      2000         1999
<S>                <C>          <C>
Gas sales (Mcf)    15,708,443   14,153,839
Oil sales (Bbls)       36,486       26,096
</TABLE>

During the first nine months of 2000, gas and oil prices were higher than during
the first nine 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 nine months ended
September 30, 2000 and 1999, respectively, was computed as shown in the
following table:

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

   Gas proceeds                   $ 37,930,505   $ 17,003,534   $ 85,686,811    $ 47,093,562
   Oil proceeds                        712,463        296,092      1,721,467         702,209
                                  ------------   ------------   ------------    ------------

Total                               38,642,968     17,299,626     87,408,278      47,795,771
                                  ------------   ------------   ------------    ------------

Less production costs:
   Severance tax - Gas               4,080,262      1,756,659      8,540,899       4,853,720
   Severance tax - Oil                  78,150         34,325        168,572          72,846
   Lease operating expenses
      and property tax(a)            3,153,169      2,243,776     11,289,538       7,888,702
   Capital expenditures(a)           4,994,236      2,720,024     14,356,455       7,991,065
   Other                                 7,551                       129,161         (95,445)
                                  ------------   ------------   ------------    ------------

Total                               12,313,368      6,754,784     34,484,625      20,710,888
                                  ------------   ------------   ------------    ------------

Net profits                         26,329,600     10,544,842     52,923,653      27,084,883
                                  ------------   ------------   ------------    ------------

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

Subtotal                            19,747,200      7,908,631     39,692,740      20,313,662
Other(b)                                                           3,740,000
                                  ------------   ------------   ------------    ------------

Royalty income                    $ 19,747,200   $  7,908,631   $ 43,432,740    $ 20,313,662
                                  ============   ============   ============    ============
</TABLE>

(a)  Includes charges received from BROG during the nine months ended September
     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
September 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 Royalty. 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 Co., et al.
                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 twice
                denied class certification. Discovery in this matter is closed.
                The defendants filed multiple motions for summary judgment and
                partial summary judgment. By Memorandum Opinion dated November
                6, 2000, the Court granted the defendants' motions as to Counts
                II and III and granted partial summary judgment as to Counts I
                and IV. The case will proceed to trial on the issue of breach of
                contract as to some but not all of the leases complained of.
                Because the Memorandum Opinion is subject to appeal, and 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, but no payment has yet been
                received. BROG has informed the Trust that its preliminary
                calculations indicate that the proportion of the settlement
                proceeds with will be attributable to the Trust is $263,606.

ITEM 6.         EXHIBITS AND REPORTS ON FORM 8-K

                (a)  Exhibits



                                      -15-
<PAGE>   16

                     (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

                (b)  Reports on Form 8-K

                     The Trust filed a report on Form 8-K on October 27, 2000.
                     In the report, the Trust reported, under Item 5, that it
                     had announced the upward adjustment of anticipated capital
                     expense of the Trust for fiscal year ending December 31,
                     2000.



                                      -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: November 14, 2000


               (The Trust has no directors or executive officers.)



<PAGE>   18

                                INDEX TO EXHIBITS


<TABLE>
<CAPTION>
               EXHIBIT
               NUMBER                                EXHIBIT
               ------                                -------
<S>                       <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.