THE FIRST AMENDMENT TO THE GAS SALES AGREEMENT

                                     BETWEEN

                         PETROLEUM AUTHORITY OF THAILAND

                                       AND

                             B8/32 PARTNERS LIMITED

                                 THAIPO LIMITED

                                THAI ROMO LIMITED

                              PALANG SOPHON LIMITED

                                NOVEMBER 12, 1997
<PAGE>
THE FIRST AMENDMENT TO THE GAS SALES AGREEMENT (the GSA) dated November 7th,
1995, is hereby made this November 12th, 1997.

BETWEEN

(1) PETROLEUM AUTHORITY OF THAILAND, having its principal office at 555
Vibhavadi Rangsit Road, Bangkok 10900 (hereinafter called "PTT");

(2) THAIPO LIMITED, a company duly incorporated and existing under the laws of
Thailand and having its registered office at 18th Floor, B.B. Building, 54 Asoke
Road, Sukhumvit 21, Bangkok 10110 (hereinafter called "THAIPO");

(3) THAI ROMO LIMITED, a company duly incorporated and existing under the laws
of Thailand and having its registered office at 19th floor, B.B. Building, 54
Asoke Road, Sukhumvit 21, Bangkok 10110 (hereinafter called "THAI ROMO");

(4) PALANG SOPHON LIMITED, a company duly incorporated and existing under the
laws of Thailand and having its registered office at 19th floor, B.B. Building,
54 Asoke Road, Sukhumvit 21, Bangkok 10110 (hereinafter called "SOPHON"); and

(5) B8/32 PARTNERS LIMITED, a company duly incorporated and existing under the
laws of Thailand and having its registered office at 19th floor, B.B. Building,
54 Asoke Road, Sukhumvit 21, Bangkok 10110 (hereafter called "B8/32 PARTNERS").

THAIPO, THAI ROMO AND SOPHON hereinafter all collectively
     called "Original Concessionaire"

WHEREAS:

(A) The Original Concessionaire has indicated to PTT that additional Natural Gas
has been found in the Concession Area at the Benchamas/Pakakrong Fields as
defined in the First Schedule, Part II, as hereinafter amended, and that such
Natural Gas can be developed in conjunction with the Natural Gas being developed
in the Tantawan Field in the GSA Area;

(B) The parties involved at the Benchamas/Pakakrong Fields include B8/32
PARTNERS who is not and Original Concessionaire under the GAS;

(C) The Original Concessionaire has indicated to PTT that they and the B8/32
Partners wish to sell the Natural Gas from the Benchamas/Pakakrong Fields to PTT
and PTT has indicated its willingness to purchase Natural Gas from the
Benchamas/Pakakrong Fields.

                                       -2-
<PAGE>
NOW IT IS HEREBY AGREED AS FOLLOWS THAT THE GSA SHALL BE AMENDED BY THIS FIRST
AMENDMENT TO REFLECT:

1. That the Concessionaire under the GSA shall include, as of the effective date
of this First Amendment, B8/32 Partners.

2. That recital (A) of the GSA shall be amended by the addition of the following
words: "and on the fourth (4th day of September, 1995, the Supplementary
Petroleum Concession No. 2 to Petroleum Concession 1/2534/36;"

3. That Clause 1.5 of the GSA shall be amended by the addition of the following
words; "and Supplementary Petroleum Concession No. 2 to Petroleum Concession No.
1/2534/36, dated September 4, 1995."

4. That Clause 1.19 of the GSA shall be amended by the addition of the following
words: "Delivery Point shall include either Delivery Points described in the
amended Fourth Schedule or both Delivery Points as the context requires."

5. That Clause 1.25 shall be amended to read "GSA Area means that part of the
Concessionaire Area described in the First Schedule, as amended by the First
Amendment Part II, and dedicated to the service of the GSA."

6. That Clause 4.1 (line 1) the "Delivery Point" shall be amended to read the
"Delivery Points."

7. That Clause 5.1 the "Delivery Point" (lines 1 and 4) shall be amended to read
the "Delivery Points."

8. That Clause 6.3 shall be amended to read as follows;

     "An initial Run-In Period shall follow the Date of Commencement of Delivery
(DCD) and a run-in Period shall also commence the effective date of each
increase in the DCQ pursuant to Subclause 6.6(iv); and such Run-In Period shall
terminate at the earlier of the completion of the seventy-two (72) hour test or
three (3) months. The first day following the initial Run-In Period shall be
referred to as the Contractual Delivery Date (CDD). The Run-In Period shall be
for the purpose of proving the facilities required for the performance of the
initial obligations of both the Concessionaire and PTT and during such Run-In
Period both the Concessionaire and PTT shall use reasonable endeavours
respectively to deliver and take Sales Gas."

9. That Clause 6.3(I) shall be amended by the deletion of the first paragraph
and the addition of the following paragraph:

                                       -3-
<PAGE>
     "The Concessionaire shall, during the run in period, complete a test of
seventy-two (72) consecutive hours. During the run-in period, concessionaire
shall notify PTT that the Concessionaire is ready to attempt a seventy-two (72)
hour test and PTT shall nominate the rate of delivery in accordance with Clause
6.12 and the Concessionaire shall offer continuously to PTT Sales Gas of quality
and at pressure consistent with the PTT nomination. If the Concessionaire is
unable, for whatever reason other than PTT's inability to take, to complete the
continuous seventy-two (72) hour period, the test shall be restarted after the
Concessionaire notifies PTT of its desire to restart the seventy-two (72) hour
test:

10. That Subclause 6.3(I) shall be amended the last paragraph to read as
follows:

     "During the initial run in period, sales gas shall be paid for at a price
of seventy-five (75) percent of current price as calculated. During all other
run-in periods sales gas delivered in excess of the DCQ immediately preceding
the increased DCQ referred to in Subclause 6.6(iv) shall be paid for at a price
of seventy-five (75) percent of Current Price as calculated."

11. That subclause 6.6(ii) shall be amended by the addition of the following
sentence; "In no event, shall the DCQ be less than 125 million cubic feet."

12. That Subclause 6.6(iii) shall be amended to change "one hundred and
twenty-five (125) to three hundred (300).

13. That subclause 6.6(iv) shall be amended by the addition of the following
paragraph:

     "Notwithstanding the above paragraph, the date of commencement for the run
in period for the DCQ, including the reserves from Benchamas/Pakakrong Fields,
shall be the date of completion of the facilities necessary for Concessionaire
to produce gas from the Benchamas/Pakakrong Fields, which date shall be August
1, 1999. Such date may be adjusted by up to 60 days by Concessionaire informing
PTT twelve (12) months in advance of the date of commencement for the run in
period. The DCQ, as determined under Clause 6.6 (ii) above, shall become
effective the date following the day the Concessionaire successfully completes
the seventy-two (72) hour test or two (2) months from the date of commencement
of the run-in period, whichever is earlier."

14. That Clause 6.17 shall be amended to change "eighty-five (85)" to "one
hundred twenty-five (125)."

                                       -4-
<PAGE>
15. That Article VII shall be amended by the addition of the following
paragraph:

 . "The Concessionaire or PTT, as mutually agreed, shall be responsible for the
building and testing of the pipeline for the delivery of Benchamas/Pakakrong
Field Sales Gas to the PTT 24-inch pipeline. The cost and expense incurred in
the design, procurement, fabrication, installation, testing and commissioning of
the pipeline shall be shared by the Concessionaire and PTT on a 65/35 basis
respectively."

16. That Clause 10.3, the last word of second paragraph shall be amended to
change "earlier" to "later."

17. That Clause 14.3 shall be amended to include the words "at the relevant
Delivery Point" immediately after the words "delivery Sales Gas" and the word
"relevant" added ahead of "Delivery Point."

18. That subject to confirmation and acceptance by PTT that the combined Field
Reserves of the Tantawan and Benchamas/Pakakrong Fields equals or exceed file
hundred (500) billion cubic feet, Clauses 15.7 and 18.5 shall no longer have any
cause or effect.

19. That Clause 25.4 shall be amended by changing "The Sophonpalnich Co., Ltd."
To read "Palang Sophon Limited," with the following change of address:

     Palang Sophon Limited
     19th floor, B.B. Building
     Asoke Road, Sukhumvit 21
     Bangkok 10110, Thailand
     Fax No. 662-260-7247
     Tel. No. 662-260-7310

20. That Clause 25.4 shall be amended to include:

     B8/32 PARTNERS LIMITED
     18th Floor, B.B. Building
     Asoke Road
     Bangkok 10110 Thailand
     Fax No. 662-260-7150
     Tel No. 662-260-7151

21. That the First Schedule Part II shall be amended to include those parts of
the Concession Area containing the Benchamas/Pakakrong Field. Such amended
schedule is attached to this First Amendment as First Schedule Part II GSA Area
(First Amendment).

                                       -5-
<PAGE>
22. That the Second Schedule: MERCURY: NIL shall be amended to read "MERCURY:
contain not more than 50 micrograms per cubic meter (by weight) with 12 months
to rectify any excess amount."

23. That the Fourth Schedule shall be amended by changing "single delivery
point" to "two delivery points" in the first paragraph and in the second
paragraph changing "Delivery Point" to "Tantawan Delivery Point."

24. That at the end of the Fourth Schedule a new paragraph will be added to
state: "The Benchamas/Pakakrong Delivery Point shall be agreed between
Concessionaire and PTT within 120 days of the Effective Date of this First
Amendment. If additional time is required to agree and confirm a mutually
acceptable location, both parties agree to use reasonable endeavours to promptly
achieve and confirm an acceptable location."

25. That the Fifth Schedule (Parental Guarantee) attached to this First
Amendment is a Parental Guarantee of performance under the GSA for B8/32
Partners.

26. The provisions of this Amendment shall constitute a supplement to the GSA.
To the extent that there is any conflict or inconsistency between the terms of
the GSA and the terms of this First Amendment, the terms of this First Amendment
shall prevail.

27. Except as amended hereby the GSA shall remain in full force and effect.

28. This First Amendment shall be governed by and construed in accordance with
the laws of Thailand.

29. This First Amendment shall be effective from the execution date.

                                       -6-
<PAGE>
IN WITNESS WHEREOF this First Amendment has been signed by the duly authorized
representatives of the parties on the day and year first above written.

/s/  P. SOOHAWERT                       /s/  ILLEGIBLE
--------------------------------   -------------------------------
Signed for and on behalf of             Witness
PETROLEUM AUTHORITY
     OF THAILAND

/s/  JEFF SEVERIN                       /s/  ILLEGIBLE
--------------------------------   -------------------------------
Signed for and on behalf of             Witness
THAIPO LIMITED

/s/  THOMAS E. RANKIN                   /s/  ILLEGIBLE
--------------------------------   -------------------------------
Signed for and on behalf of             Witness
THAI ROMO LIMITED

/s/  ILLEGIBLE                          /s/  SUNEE P.
--------------------------------   -------------------------------
Signed for and on behalf of             Witness
PALANG SOPHON LIMITED

/s/  JEFF SEVERIN                       /s/  RATTIKAN C.
--------------------------------   -------------------------------
Signed for and on behalf of             Witness
B8/32 PARTNERS LTD.

                                       -7-
<PAGE>
ATTACHMENTS:

First Schedule Part II
Fifth Schedule

                                       -8-

<PAGE>


                                               
POINT                  LATITUDE                LONGITUDE
CODE                DEG  MINS SEC            DEG  MINS SEC
----                -------------            -------------
A                   10   18   00.00"N        101  24   00.0"E
B                   10   18   00.00"N        Intersecting
                                             with the Declared Cambodian
                                             Continental
                                             Shelf (1972)

C                   10   16   50.00"N        101  29   30.0"E
D                   10   09   00.00"N        101  30   00.0"E
E                   10   09   00.00"N        101  27   00.0"E
F                   10   00   00.00"N        101  28   20.0"E
G                   10   00   00.00"N        101  24   00.0"E

BENCHAMAS/PAKAKRONG FIELD:



POINT                  LATITUDE                LONGITUDE
CODE                DEG  MINS SEC            DEG  MINS SEC

A                   10   39   00.00"N        101  14   00.0"E
B                   10   31   00.00"N        101  14   00.0"E
C                   10   31   00.00"N        101  12   00.0"E
D                   10   28   00.00"N        101  12   00.0"E
E                   10   28   00.00"N        101  11   30.0"E
F                   10   21   30.00"N        101  11   30.0"E
G                   10   21   30.00"N        101  14   00.0"E
H                   10   22   00.00"N        101  14   00.0"E
I                   10   22   00.00"N        101  16   00.0"E
J                   10   22   30.00"N        101  16   00.0"E
K                   10   22   30.00"N        101  20   00.0"E
L                   10   39   00.00"N        101  20   00.0"E

<PAGE>

                               PARENTAL GUARANTEE

                                November 7, 1997

TO PETROLEUM AUTHORITY OF THAILAND

Dear Sirs:

In consideration of your entering into an Agreement with B8/32 Partners Limited
and others for the purchase from them of natural gas on the terms and conditions
therein mentioned, we guarantee the due performance by B8/32 Partners Limited of
all its obligations under the said Agreement.

Yours faithfully,

THAI ROMO HOLDINGS, INC.

/s/  DAVID F. CHAVENSON
By:  David F. Chavenson
     Vice President

POGO PRODUCING COMPANY

/s/  RONALD B. MANNING
By:  Ronald B. Manning
     Vice President

PALANG SOPHON LTD.

/s/ SIRITAS PRASERT-MANUKITCH                /s/  CHOTE S.
By:  Siritas Prasert-Manukitch               Chote Sophonpanich
     President                               Director