-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 HHbaUiza9vrd2pVNeACjKOIIYxN2eEPgPpwvPAtppenUzLKFIKGQsa7gUi7LjP+v
 IivZajl31W/EhF0/pIjwQA==

<SEC-DOCUMENT>0001047469-04-029153.txt : 20040920
<SEC-HEADER>0001047469-04-029153.hdr.sgml : 20040920
<ACCEPTANCE-DATETIME>20040920163613
ACCESSION NUMBER:		0001047469-04-029153
CONFORMED SUBMISSION TYPE:	8-K
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20040920
ITEM INFORMATION:		Regulation FD Disclosure
ITEM INFORMATION:		Financial Statements and Exhibits
FILED AS OF DATE:		20040920
DATE AS OF CHANGE:		20040920

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MESA ROYALTY TRUST/TX
		CENTRAL INDEX KEY:			0000313364
		STANDARD INDUSTRIAL CLASSIFICATION:	OIL ROYALTY TRADERS [6792]
		IRS NUMBER:				746284806
		STATE OF INCORPORATION:			TX
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		8-K
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-07884
		FILM NUMBER:		041037783

	BUSINESS ADDRESS:	
		STREET 1:		712 MAIN STREET
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77210
		BUSINESS PHONE:		7132165100

	MAIL ADDRESS:	
		STREET 1:		P O BOX 4717
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77210
</SEC-HEADER>
<DOCUMENT>
<TYPE>8-K
<SEQUENCE>1
<FILENAME>a2143740z8-k.htm
<DESCRIPTION>8-K
<TEXT>
<HTML>
<HEAD>

</HEAD>
<BODY BGCOLOR="#FFFFFF" LINK=BLUE  VLINK=PURPLE>
<BR>
<FONT SIZE=3 ><A HREF="#04HOU1536_1">QuickLinks</A></FONT>
<font size=3> -- Click here to rapidly navigate through this document</font>

<P><FONT SIZE=2>
<hr noshade width=100% align=left size=4>
<hr noshade width=100% align=left size=1> </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=5><B>UNITED STATES<BR>
SECURITIES AND EXCHANGE COMMISSION<BR>  </B></FONT><FONT SIZE=2><B>Washington, D.C. 20549  </B></FONT></P>

<BR>
<P ALIGN="CENTER"><FONT SIZE=5><B>FORM 8-K  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=3><B>CURRENT REPORT<BR>
Pursuant to Section&nbsp;13 or 15(d) of the Securities Exchange Act of 1934  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>Date of Report (Date of earliest event reported): </FONT><FONT SIZE=2><B>September&nbsp;20, 2004</B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=5><B>Mesa Royalty Trust<BR>  </B></FONT><FONT SIZE=2>(Exact name of registrant as specified in its charter) </FONT></P>

<!-- User-specified TAGGED TABLE -->
<TABLE WIDTH="100%" BORDER=0 CELLSPACING=0 CELLPADDING=0>
<TR VALIGN="TOP">
<TD WIDTH="32%" ALIGN="CENTER"><FONT SIZE=2><B>Texas<BR> </B></FONT><FONT SIZE=2>(State or other jurisdiction of incorporation)</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="32%" ALIGN="CENTER"><FONT SIZE=2><B>1-7884<BR> </B></FONT><FONT SIZE=2>(Commission File Number)</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="32%" ALIGN="CENTER"><FONT SIZE=2><B>76-6284806<BR> </B></FONT><FONT SIZE=2>(IRS Employer Identification No.)</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD COLSPAN=3 ALIGN="CENTER"><BR><FONT SIZE=2><B>JPMorgan Chase Bank, Trustee<BR>
Institutional Trust Services<BR>
700 Lavaca Street<BR>
Austin, Texas<BR> </B></FONT><FONT SIZE=2>(Address of principal executive offices)</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="32%" ALIGN="CENTER"><BR><FONT SIZE=2><B>&nbsp;<BR>
&nbsp;&nbsp;<BR>
&nbsp;&nbsp;<BR>
78701<BR> </B></FONT><FONT SIZE=2>(Zip Code)</FONT></TD>
</TR>
</TABLE>
<!-- end of user-specified TAGGED TABLE -->

<P ALIGN="CENTER"><FONT SIZE=2>Registrant's telephone number, including area code: </FONT><FONT SIZE=2><B>(512)&nbsp;479-2562  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B> NOT APPLICABLE<BR>  </B></FONT><FONT SIZE=2>(Former name or former address, if changed since last report.) </FONT></P>

<P><FONT SIZE=2>Check
the appropriate box below if the Form&nbsp;8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions: </FONT></P>

<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2><FONT FACE="WINGDINGS">&#111;</FONT></FONT></DT><DD><FONT SIZE=2>Written
communications pursuant to Rule&nbsp;425 under the Securities Act (17 CFR 230.425)
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2><FONT FACE="WINGDINGS">&#111;</FONT></FONT></DT><DD><FONT SIZE=2>Soliciting
material pursuant to Rule&nbsp;14a-12 under the Exchange Act (17 CFR 240.14a-12)
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2><FONT FACE="WINGDINGS">&#111;</FONT></FONT></DT><DD><FONT SIZE=2>Pre-commencement
communications pursuant to Rule&nbsp;14d-2(b) under the Exchange Act (17 CFR
240.14d-2(b))
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2><FONT FACE="WINGDINGS">&#111;</FONT></FONT></DT><DD><FONT SIZE=2>Pre-commencement
communications pursuant to Rule&nbsp;13e-4(c) under the Exchange Act (17 CFR
240.13e-4(c)) </FONT></DD></DL>
<BR>

<P><FONT SIZE=2><hr
noshade width=100% align=left size=1>
<hr noshade width=100% align=left size=4> </FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
<!-- ZEQ.=1,SEQ=1,EFW="2143740",CP="MESA ROYALTY TRUST",DN="1",CHK=937114,FOLIO='blank',FILE='DISK003:[04HOU6.04HOU1536]BE1536A.;3',USER='ARILEY',CD='20-SEP-2004;13:05' -->
<!-- THIS IS THE END OF A COMPOSITION COMPONENT -->

<P><FONT SIZE=2><A
NAME="page_de1536_1_2"> </A> </FONT></P>

<!-- TOC_END -->

<P><FONT SIZE=2><A
NAME="de1536_item_7.01_regulation_fd_disclosure."> </A>
<A NAME="toc_de1536_1"> </A>
<BR></FONT><FONT SIZE=2><B>Item 7.01 Regulation FD Disclosure.    <BR>    </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;On September&nbsp;20, 2004, Mesa Royalty Trust issued a press release announcing Mesa Royalty Trust's royalty income, income distribution and trust expenses for
the month of September&nbsp;2004. A copy of the press release is filed as Exhibit&nbsp;99.1 hereto and is incorporated herein by reference. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Pursuant
to General Instruction B.2 of Form&nbsp;8-K and Securities and Exchange Commission Release No.&nbsp;33-8176, the press release attached as
Exhibit&nbsp;99.1 is not "filed" for purposes of Section&nbsp;18 of the Securities Exchange Act of 1934, as amended, is not subject to the liabilities of that section and is not deemed
incorporated by reference in any filing under the Securities Act of 1933, as amended, but is instead furnished for purposes of that instruction. </FONT></P>

<P><FONT SIZE=2><A
NAME="de1536_item_9.01_financial_statements_and_exhibits."> </A>
<A NAME="toc_de1536_2"> </A>
<BR></FONT><FONT SIZE=2><B>Item 9.01 Financial Statements and Exhibits.    <BR>    </B></FONT></P>

<UL>
<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2><B>(c)</B></FONT></DT><DD><FONT SIZE=2>Exhibits. </FONT></DD></DL>
<UL>

<P><FONT SIZE=2>Exhibit&nbsp;99.1&nbsp;&nbsp;&nbsp;&nbsp;Mesa
Royalty Trust Press Release dated September&nbsp;20, 2004. </FONT></P>

</UL>
</UL>
<P ALIGN="CENTER"><FONT SIZE=2>2</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
<!-- ZEQ.=1,SEQ=2,EFW="2143740",CP="MESA ROYALTY TRUST",DN="1",CHK=946226,FOLIO='2',FILE='DISK003:[04HOU6.04HOU1536]DE1536A.;3',USER='ARILEY',CD='20-SEP-2004;13:06' -->
<UL>
<UL>
</UL>
</UL>
<!-- THIS IS THE END OF A COMPOSITION COMPONENT -->
<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="page_jc1536_1_3"> </A> </FONT></P>

<!-- TOC_END -->
<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="jc1536_signatures"> </A>
<A NAME="toc_jc1536_1"> </A>
<BR></FONT><FONT SIZE=2><B>SIGNATURES    <BR>    </B></FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;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
hereunto duly authorized. </FONT></P>

<!-- User-specified TAGGED TABLE -->
<TABLE WIDTH="100%" BORDER=0 CELLSPACING=0 CELLPADDING=0>
<TR VALIGN="TOP">
<TD WIDTH="39%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD COLSPAN=2><FONT SIZE=2>Mesa Royalty Trust</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="39%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="4%"><FONT SIZE=2><BR>
By:</FONT></TD>
<TD WIDTH="54%"><FONT SIZE=2><BR>
JPMorgan Chase Bank, as Trustee</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="39%"><FONT SIZE=2><BR>
Date: September&nbsp;20, 2004</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="4%"><FONT SIZE=2><BR>
By:</FONT></TD>
<TD WIDTH="54%"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>MIKE ULRICH</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Mike Ulrich<BR>
Vice President and Trust Officer</FONT></TD>
</TR>
</TABLE>
<!-- end of user-specified TAGGED TABLE -->

<P ALIGN="CENTER"><FONT SIZE=2>3</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
<!-- ZEQ.=1,SEQ=3,EFW="2143740",CP="MESA ROYALTY TRUST",DN="1",CHK=195758,FOLIO='3',FILE='DISK003:[04HOU6.04HOU1536]JC1536A.;2',USER='ARILEY',CD='20-SEP-2004;13:07' -->
<!-- THIS IS THE END OF A COMPOSITION COMPONENT -->
<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="page_ka1536_1_4"> </A> </FONT></P>

<!-- TOC_END -->
<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="ka1536_exhibit_index"> </A>
<A NAME="toc_ka1536_1"> </A>
<BR></FONT><FONT SIZE=2><B>EXHIBIT INDEX    <BR>    </B></FONT></P>

<!-- User-specified TAGGED TABLE -->
<TABLE WIDTH="79%" BORDER=0 CELLSPACING=0 CELLPADDING=0>
<TR VALIGN="BOTTOM">
<TH WIDTH="8%" ALIGN="LEFT"><FONT SIZE=1><B>Exhibit<BR> </B></FONT><HR NOSHADE></TH>
<TH WIDTH="3%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="89%" ALIGN="LEFT"><FONT SIZE=1><B>Description<BR> </B></FONT><HR NOSHADE></TH>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2>99.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2>Mesa Royalty Trust Press Release dated September 20, 2004.</FONT></TD>
</TR>
</TABLE>
<!-- end of user-specified TAGGED TABLE -->

<P ALIGN="CENTER"><FONT SIZE=2>4</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
<!-- ZEQ.=1,SEQ=4,EFW="2143740",CP="MESA ROYALTY TRUST",DN="1",CHK=786079,FOLIO='4',FILE='DISK003:[04HOU6.04HOU1536]KA1536A.;2',USER='ARILEY',CD='20-SEP-2004;13:08' -->
<!-- THIS IS THE END OF A COMPOSITION COMPONENT -->
<BR>
<P><br><A NAME="04HOU1536_1">QuickLinks</A><br></P><!-- TOC_BEGIN -->
<UL>
<FONT SIZE=2><A HREF="#toc_de1536_1">Item 7.01 Regulation FD Disclosure.</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_de1536_2">Item 9.01 Financial Statements and Exhibits.</A></FONT><BR>
</UL>
<!-- TOC_BEGIN -->
<FONT SIZE=2><A HREF="#toc_jc1536_1">SIGNATURES</A></FONT><BR>
<!-- TOC_BEGIN -->
<FONT SIZE=2><A HREF="#toc_ka1536_1">EXHIBIT INDEX</A></FONT><BR>
<!-- SEQ=,FILE='QUICKLINK',USER=ARILEY,SEQ=,EFW="2143740",CP="MESA ROYALTY TRUST",DN="1" -->
<!-- TOCEXISTFLAG -->
</BODY>
</HTML>

</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-99.1
<SEQUENCE>2
<FILENAME>a2143740zex-99_1.htm
<DESCRIPTION>EXHIBIT 99.1
<TEXT>
<HTML>
<HEAD>

</HEAD>
<BODY BGCOLOR="#FFFFFF" LINK=BLUE  VLINK=PURPLE>
<BR>
<FONT SIZE=3 ><A HREF="#04HOU1536_2">QuickLinks</A></FONT>
<font size=3> -- Click here to rapidly navigate through this document</font>
<!-- TOC_END -->
<P ALIGN="RIGHT"><FONT SIZE=2><A
NAME="km1536_exhibit_99.1"> </A>
<A NAME="toc_km1536_1"> </A>
<BR></FONT><FONT SIZE=2><B>Exhibit 99.1    <BR>    </B></FONT></P>

<P><FONT SIZE=2>Mesa-Royalty-Trust </FONT></P>

<P><FONT SIZE=2><B>Mesa Royalty Trust Announces Trust Income for September&nbsp;2004  </B></FONT></P>

<!-- User-specified TAGGED TABLE -->
<TABLE WIDTH="100%" BORDER=0 CELLSPACING=0 CELLPADDING=0>
<TR VALIGN="TOP">
<TD WIDTH="49%"><BR><FONT SIZE=5><B>MESA ROYALTY TRUST<BR>
JPMorgan Chase Bank, Trustee</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=5><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="49%" ALIGN="CENTER"><BR><FONT SIZE=5><B><I>NEWS<BR>
RELEASE</I></B></FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD COLSPAN=3 ALIGN="CENTER"><HR NOSHADE></TD>
</TR>
</TABLE>
<!-- end of user-specified TAGGED TABLE -->


<P><FONT SIZE=2><B>FOR IMMEDIATE RELEASE  </B></FONT></P>

<P><FONT SIZE=2>AUSTIN,
TEXAS September&nbsp;20, 2004&#151;Mesa Royalty Trust (NYSE symbol-MTR) announced the Trust income distribution for the month of September&nbsp;2004. Unitholders of
record on September&nbsp;30, 2004 will receive distributions amounting to $748,264 or $0.401517732 per unit payable on October&nbsp;29, 2004. Royalty income from the San Juan Basin Properties
totaled $305,640. Royalty income from the Hugoton Properties totaled $444,307. </FONT></P>

<P><FONT SIZE=2>The
extent of future distributions from the properties in which the Trust has an interest will continue to be dependent on normal factors associated with oil and gas operations such as oil and gas
production levels, prices and associated cost, accruals for future abandonment costs, timing and extent of capital expenditures. </FONT></P>

<!-- User-specified TAGGED TABLE -->
<TABLE WIDTH="100%" BORDER=0 CELLSPACING=0 CELLPADDING=0>
<TR VALIGN="TOP">
<TD WIDTH="10%"><FONT SIZE=2><B>Contact:</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="88%"><FONT SIZE=2><B>Mesa Royalty Trust<BR>
JPMorgan Chase Bank, as Trustee<BR>
Mike Ulrich<BR>
1(800)&nbsp;852-1422<BR>
(512)&nbsp;479-2562</B></FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD COLSPAN=3><FONT SIZE=2><B><BR>
www.businesswire.com/cnn/mtr.htm</B></FONT></TD>
</TR>
</TABLE>
<!-- end of user-specified TAGGED TABLE -->


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;P.O.&nbsp;Box 550 Austin, TX 78789 </FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
<!-- ZEQ.=1,SEQ=1,EFW="2143740",CP="MESA ROYALTY TRUST",DN="2",CHK=275716,FOLIO='blank',FILE='DISK003:[04HOU6.04HOU1536]KM1536A.;4',USER='ARILEY',CD='20-SEP-2004;13:13' -->
<!-- THIS IS THE END OF A COMPOSITION COMPONENT -->
<BR>
<P><br><A NAME="04HOU1536_2">QuickLinks</A><br></P><!-- TOC_BEGIN -->
<UL>
<FONT SIZE=2><A HREF="#toc_km1536_1">Exhibit 99.1</A></FONT><BR>
</UL>
<!-- SEQ=,FILE='QUICKLINK',USER=ARILEY,SEQ=,EFW="2143740",CP="MESA ROYALTY TRUST",DN="2" -->
<!-- TOCEXISTFLAG -->
</BODY>
</HTML>

</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----
