3-D SEISMIC PARTICIPATION AGREEMENT


     THIS  AGREEMENT  dated  as of May 30,  1996,  by and  between  FINA OIL AND
CHEMICAL  COMPANY,  ("FINA")  a  Delaware  corporation,  14950  Heathrow  Forest
Parkway, Houston, Texas 77032 and DENBURY MANAGEMENT,  INC. ("DENBURY"), a Texas
corporation,  17304 Preston Road, Suite 200, Dallas,  Texas 77252 (collectively,
FINA  and  Denbury  shall  be  referred  to as the  "FINA  GROUP");  and  acting
individually  herein SCANA PETROLEUM  RESOURCES,  INC. ("SPR"), a South Carolina
Corporation, 1200 Smith Street, Suite 500, Houston, Texas 77002-4308 ("SPR") and
FRONTIER NATURAL GAS CORPORATION  ("FRONTIER"),  an Oklahoma  corporation,  9400
North Broadway Extension, Oklahoma City, Oklahoma 73114; SOUTH COAST EXPLORATION
COMPANY ("SOUTH COAST"),  a Texas corporation,  Two Post Oak Central,  1980 Post
Oak Boulevard, Suite 2050, Houston, Texas 77056; SOCO EXPLORATION L.P. ("SOCO"),
a Texas  Limited  Partnership,  Two Post Oak Central,  1980 Post Oak  Boulevard,
Suite 2050, Houston, Texas 77056; MATAGORDA PRODUCTION COMPANY ("MATAGORDA"),  a
Texas corporation, 675 Bering Drive, Suite 850, Houston, Texas 77057 and POLARIS
EXPLORATION  CORPORATION  ("POLARIS"),  a  Texas  corporation,  P.O.  Box  2080,
Beeville, Texas 78104-2080, (collectively, the "FRONTIER GROUP").

                                   WITNESSETH:

     WHEREAS,  SPR and the  members  of the FINA  GROUP and the  members  of the
FRONTIER GROUP each are presently  engaged in the business of exploring for oil,
gas and other hydrocarbons within the state of Louisiana; and,

     WHEREAS,  SPR and the  members of the FINA GROUP own  leases,  options  and
other rights to explore  within a certain area of Terrebonne  Parish,  Louisiana
and the members of the  FRONTIER  GROUP own leases,  options and other rights to
explore  within  a  certain  area of  Terrebonne  Parish,  Louisiana  and  FINA,
individually  is the  owner  of  certain  lands  located  in a  certain  area of
Terrebonne  Parish,  Louisiana,  which areas collectively are deemed by SPR, the
FINA GROUP and the  FRONTIER  GROUP to be  prospective  for finding oil, gas and
other hydrocarbons; and,

     WHEREAS,  certain members of the FINA GROUP own certain proprietary data or
are in possession of and have a license to use certain other data,  which covers
substantially  all of FINA's  lands as well as lands  adjacent  to FINA's  lands
which the FRONTIER GROUP may not have been licensed to use; and,

     WHEREAS,  certain  members  of the  FRONTIER  GROUP  have a license  to use
certain other data which the FINA GROUP may not have been licensed to use; and,

     WHEREAS,  SPR, the FINA GROUP and the FRONTIER GROUP  recognize the benefit
of entering  into an  agreement  which  gives each access to the data  presently
owned by or licensed to the other; and,

     WHEREAS,  the  members  of the FINA GROUP and the  members of the  FRONTIER
GROUP find it in their mutual interests to enter into an agreement for using the
data of SPR, the FINA GROUP and the FRONTIER GROUP for the purposes of exploring
for oil,  gas and other  hydrocarbons  on the lands owned by FINA as well as the
adjacent lands which are covered by the leases, options to lease or other rights
to explore  owned by either  SPR,  certain  members of the FINA GROUP or certain
members of the FRONTIER GROUP and which are covered by data in the possession of
the members of SPR, the FINA GROUP and/or the FRONTIER GROUP.

     NOW  THEREFORE,  for  and in  consideration  of  the  premises  and  mutual
covenants herein  contained,  SPR, the members of the FINA GROUP and the members
of the FRONTIER GROUP do hereby covenant and agree as follows:

                                    ARTICLE 1

                               CERTAIN DEFINITIONS

     As used in this  Agreement,  the  following  words and terms shall have the
meanings here ascribed to them:


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     1.1 "Agreement" shall refer to this Agreement.

     1.2  "Contract  Area" shall mean the area within the red outline on Exhibit
"A" attached hereto and made a part hereof for all purposes.

     1.3 "Oil and Gas" shall mean oil, gas, casing head gas, gas condensate, and
all other  liquid  or  gaseous  hydrocarbons  and  other  marketable  substances
produced therewith,  unless an intent to limit the inclusiveness of this term is
specifically stated.

     1.4 "Oil and Gas Interests"  shall mean unleased fee and mineral  interests
in tracts of lands lying within the  Contract  Area which are owned by or within
the control of any of the parties to this Agreement.

     1.5 "Oil and Gas Lease," "Lease" and "Leasehold" shall mean the oil and gas
leases or options to acquire  oil and gas leases  covering  tracts of land lying
within the  Contract  Area which are either  owned by any of the parties to this
Agreement  or which any party to this  Agreement is entitled to or may acquire a
future interest in.

     1.6 FINA Fee Lands  shall  mean any and all lands or Oil and Gas  Interests
within the Contract Area presently  owned in fee by FINA. The FINA Fee Lands are
depicted in yellow on Exhibit "A" to this Agreement.

     1.7 "FINA GROUP  Leases"  shall mean Oil and Gas leases,  options to lease,
operating  rights and other Oil and Gas Interests lying within the Contract Area
which are owned or  committed  to SPR  and/or any member of the FINA GROUP as of
the Effective Date. FINA GROUP Leases are depicted in red on Exhibit "A" to this
Agreement.

     1.8  "FRONTIER  GROUP  Leases"  shall mean Oil and Gas  leases,  options to
lease,  operating  rights  and  other Oil and Gas  interests  lying  within  the
Contract Area which are owned by any member of the FRONTIER GROUP as of December
31,  1996.  FRONTIER  GROUP  Leases are depicted in green on Exhibit "A" and set
forth on Exhibit  "A-1" to this  Agreement.  FRONTIER  GROUP  Leases  shall also
include  any  leases or options to lease  within the area  depicted  in green on
Exhibit "A" which have multiple  lessors  owning an  individual  interest in the
leased  lands as  evidenced  by at least  one  lessor's  execution  having  been
acknowledged  on or before  December 31,  1996.  In the event the balance of the
unsigned lessors have not executed their respective leases by December 31, 1996,
said interests  associated with the unsigned  lessors will become subject to the
AMI  provisions  set forth in  provision  9.1 hereof.  In addition to the leases
depicted in green, FRONTIER GROUP Leases shall include those leases described on
Exhibit "A- 3" and acquired prior to May 30, 1996 attached  hereto,  which cover
undivided interests in tracts within the Contract Area but are not colored green
on Exhibit "A".

     1.9 "Effective Date" shall mean May 30, 1996.

     1.10 "Designated Member" shall mean FINA Oil and Chemical Company as to the
FINA GROUP and Polaris Exploration Corporation as to the FRONTIER GROUP.

     1.11 "JOA" shall mean the  operating  agreement  for a given  Contract Area
substantially in the form as that attached hereto as Exhibit "E".

     1.12 "Disputed  Acreage" shall mean those lands within the Contract Area as
to which a dispute  exists  between FINA and the State of Louisiana with respect
to the  ownership  thereof.  Said lands are colored green hatched on Exhibit "A"
attached  hereto.  For  purposes of this  Agreement,  and as between the parties
hereto,  unless and until a determination  is made, it shall be assumed that the
Disputed  Acreage  is  actually  owned  80% by  FINA  and  20% by the  State  of
Louisiana.  Such  ownership  percentages  shall be adjusted  with respect to any
portion of the Disputed  Acreage as to which a  determination  or  settlement is
made as between  FINA and the State of  Louisiana  on the  percentage  ownership
interests of such Disputed Acreage.

     1.13 "Payout" shall mean that point in time when one hundred percent (100%)
of the gross  income  received  from the sale of oil and gas  production  from a
well, less Lessor's royalty, the overriding royalty interest reserved by Laurent
Oil & Gas, Inc. and Leo R. Bader, other overriding royalty interest burdens, and
production  and  severance  taxes,  is equal to the costs  incurred in drilling,


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testing, completing, equipping, and operating such well.

     Use of the terms  "group",  "FRONTIER  GROUP" or "FINA  GROUP"  shall mean,
unless the context  otherwise  clearly  indicates,  each and every member of the
applicable  group  and their  respective  subsidiaries,  parents,  partnerships,
affiliates  or other  person or entity owned or  controlled  by or which owns or
controls any such member;  provided,  however, that such terms shall not include
and this  Agreement  shall not be binding on  Equitable  Resources,  Inc. or any
subsidiary  or  affiliate  thereof  which  are  not  signatory  parties  to this
Agreement.  Unless the context  otherwise clearly  indicates,  words used in the
singular include the plural, the plural includes the singular and any references
to gender includes both the masculine and the feminine. The Designated Member of
each  group  agrees  by  its  execution   hereof  to  act  as  an  uncompensated
administrator  and  facilitator  for its group as an  accommodation  only.  Each
Designated  Member agrees to attempt to carry out its  obligations as Designated
Members  hereunder  with  ordinary  care and  diligence,  but each party  hereto
understands and agrees that its Designated Member shall have no liability to any
such party for any delays,  omissions  or other errors it may commit in relating
any rights,  duties or other obligations,  including any individual party and/or
group  elections  called  for  herein,  for  which  such  Designated  Member  is
responsible for  communicating  to its group members,  except as result from the
gross negligence or willful  misconduct of such Designated  Member.  In no event
shall  either  Designated  Member  be  liable  to any  member  of its  group  in
connection  with any alleged  failure to carry out its obligations as Designated
Member for any special,  indirect or consequential  damages,  including  without
limitation,  lost profits. A Designated Member may resign at any time. Any group
shall have the power to elect a new Designated Member at any time. Such election
shall  require  twenty  (20) days prior  written  notice and shall be decided by
working interest  majority.  No such change in a group's Designated Member shall
be effective  upon the other  parties  hereto  until such parties have  received
written  notice of the change in such  Designated  Member,  as  evidenced by the
signature  and  approval  of all of  the  parties  in  the  group  changing  its
Designated Member.

                                    ARTICLE 2

                                    THE LANDS

     2.1 Lands,  Oil and Gas Interests  and Oil and Gas Leases  Committed to the
Agreement.  This  Agreement  shall  cover and affect all the lands,  Oil and Gas
Interests and Oil and Gas Leases lying within the Contract Area  including,  but
not limited to, the FINA GROUP Leases,  the FRONTIER GROUP Leases,  the unleased
portion of the  entirety of the FINA Fee Lands as well as those of other  owners
not under oil and gas lease or  contractually  committed by the owner thereof to
an unrelated third party by the terms of another agreement actually in existence
on the Effective Date. Each party to this Agreement  hereby commits to the terms
and conditions hereof, and agrees to lease, convey, assign or otherwise transfer
to each and every other party  hereto  their  respective  interests  in the FINA
GROUP Leases,  the FRONTIER  GROUP Leases and the FINA Fee Lands which are owned
or controlled by any such party as of the Effective  Date, to the extent located
within the  Contract  Area,  whether or not marked or  otherwise  designated  on
Exhibit A. During the  existence of this  Agreement,  no party may sell,  lease,
convey,  assign,  encumber,  mortgage,  pledge or  contract  in any manner  with
respect to the FINA Group  Leases,  the  FRONTIER  GROUP  Leases or the FINA Fee
Lands,  in any way which would impair or prejudice the rights of any other party
in or to such  interests  as  provided  for in this  Agreement.  No wells may be
drilled or other operations  conducted in connection with the exploration for or
the  production of oil or gas from the Contract Area prior to the  completion of
the 3-D Survey and  receipt of the fully  processed  data set  without the prior
written consent of all parties hereto, nor after receipt of such data set except
pursuant to this Agreement.  Notwithstanding the foregoing, such restrictions on
drilling and other  operations  shall not apply to Initially  Excluded  Lands as
long as they remain excluded,  or to reservoirs,  the entirety of which are, and
pursuant  to this  Agreement,  will  continue to be owned 100% by a party to the
exclusion of all other parties.

     2.2 Lands, Oil and Gas Interests and Oil and Gas Leases Initially  Excluded
from this Agreement.  This Agreement does not cover lands, Oil and Gas Interests
or Oil and Gas Leases which are leased or  contractually  committed by the owner
thereof  to an  unrelated  third  party by the terms of  another  lease or other
agreement  actually in existence on the Effective Date (the "Initially  Excluded
Lands").  Each party  represents  and  warrants as  appropriate  that all of the
leases and other agreements affecting the Initially Excluded Lands are set forth
on  Exhibit  "A-2",  attached  hereto and made a part  hereof for all  purposes.
Notwithstanding  anything  contained  herein  to  the  contrary,  the  Initially
Excluded  Lands  are  limited  only to those  depicted  in blue on the  attached
Exhibit "A".


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<PAGE>
     2.3 Lands,  Oil and Gas Interests and Oil and Gas Leases to be Subsequently
Committed to this Agreement.  Should any of the Initially  Excluded Lands either
revert to or otherwise be made available to SPR, any member of the FINA GROUP or
any member of the FRONTIER GROUP during the term of this  Agreement,  then those
lands  shall  likewise  be covered  and  affected  by this  Agreement  as of the
effective date of such reversion or other availability.

                                    ARTICLE 3

                              TERM OF THE AGREEMENT

     The term of this  Agreement  shall  commence  on May 30,  1996,  and  shall
continue for sixty (60) calendar months through May 30, 2001.

                                    ARTICLE 4

                                  CONSIDERATION

     For and in  consideration  of the sum of ONE HUNDRED  DOLLARS  ($100.00) in
hand paid collectively by SPR and the FINA GROUP to the FRONTIER GROUP and other
good and valuable  consideration,  and of the other  agreements of SPR, the FINA
GROUP and the  FRONTIER  GROUP  herein and  subject to the terms and  conditions
herein  set forth,  SPR,  the  members of the FINA GROUP and the  members of the
FRONTIER  GROUP do hereby agree to join in the  execution of this  Agreement for
the purposes herein intended.

                                    ARTICLE 5

                         WORKING INTEREST OF THE PARTIES

     SPR,  the FINA  GROUP  and the  FRONTIER  GROUP  (subject  to the terms and
provisions of this Agreement,  and in particular  Articles 7 and 9 hereof) shall
each collectively be entitled to receive, pursuant to the provisions hereof, and
own a working  interest in the percentages set forth on Exhibit "B", in the FINA
Fee Lands, the FINA GROUP Leases, the FRONTIER GROUP Leases and any other lands,
leases and oil and gas interests  within the Contract Area which may be obtained
pursuant to this Agreement.

                                    ARTICLE 6

                         ACCESS TO EXISTING SEISMIC DATA

     6.1 License to use Proprietary  FINA GROUP Seismic Data. Each member of the
FRONTIER GROUP,  upon execution of this  Agreement,  is hereby granted a license
("License"), in the form set out as Exhibit "D", attached hereto and made a part
hereof for all purposes, to use all of the FINA GROUP's proprietary seismic data
within the Contract Area according thereto.

     6.2 License to use  Proprietary  FRONTIER  GROUP Seismic Data. SPR and each
member of the FINA GROUP, upon execution of this Agreement,  is hereby granted a
license  ("License"),  in the form set out as Exhibit D-1,  attached  hereto and
made a  part  hereof  for  all  purposes,  to use  all of the  FRONTIER  GROUP's
proprietary seismic data within the Contract Area according thereto.

     6.3 Access to  Non-Proprietary  FINA GROUP  Seismic  Data.  During the term
hereof and to the extent permitted by such licenses, each member of the FRONTIER
GROUP is hereby  granted  access and the right to use any and all  seismic  data
covering  lands within the Contact Area which seismic data is licensed to SPR or
any member of the FINA GROUP, to the extent such data is not also licensed or in
the possession of any member of the FRONTIER GROUP. Such access shall be granted
only on a  controlled  basis by SPR and the FINA GROUP,  at an SPR or FINA GROUP
site agreed to by the member of the FRONTIER GROUP desiring such access, subject
to the  terms  and  conditions  of the  licensing  agreements  in  place.  Those
licensing agreements are on file in FINA's or SPR's offices as applicable, and


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will remain there for the term of this  Agreement,  and by  reference  the terms
thereof are incorporated herein for all purposes.

     6.4 Access to Non-Proprietary FINA Seismic Data. FINA has acquired,  either
by purchase or as a condition of FINA's permit for a third party to acquire data
across FINA's Fee lands, licenses to use certain seismic data not owned by FINA.
As a participant in this Agreement during,  but limited to the term hereof,  SPR
and each member of the FINA GROUP and each member of the FRONTIER GROUP shall be
given  access  to and the  right to use all of the said  seismic  data in FINA's
inventory  within the Contract  Area,  but only to the extent  permitted by such
licenses.  This  access  and  right  to  use  shall  be on a  restricted  basis,
controlled  by FINA,  at a FINA site  agreed to by SPR,  the  member of the FINA
GROUP or the FRONTIER GROUP  desiring such access,  and shall be governed by the
terms and  conditions of the various  licensing  agreements  currently in place.
Those  licensing  agreements  are on file in FINA's offices and by reference are
incorporated herein for all purposes.

     6.5 Access to Non-Proprietary  FRONTIER GROUP Seismic Data. During the term
hereof and to the extent permitted by such licenses,  SPR and each member of the
FINA GROUP is hereby  granted  access  and the right to use any and all  seismic
data covering lands within the Contract Area,  which seismic data is licensed to
any member of the FRONTIER  GROUP,  to the extent such data is not also licensed
or in the  possession of SPR or any member of the FINA GROUP.  Such access shall
be granted only on a controlled basis by the FRONTIER GROUP, at a FRONTIER GROUP
site  agreed to by SPR or the member of the FINA  GROUP  desiring  such  access,
subject to the terms and conditions of the licensing  agreements in place. Those
licensing  agreements are on file in one of the FRONTIER  GROUP's  offices,  and
will remain there for the term of this  Agreement,  and by  reference  the terms
thereof are incorporated herein for all purposes.

     6.6 Access to Other Technical Data.  During the term hereof,  except to the
extent  prevented by the terms of any  agreements  with the providers of, or the
co-owners  of such  data,  SPR and  each  member  of the FINA  GROUP  and of the
FRONTIER  GROUP,  shall  also  have  access  to and the use of any and all other
technical  data owned by SPR or any member of either group which is deemed to be
useful by such  party in the  exploration  for oil and gas,  including,  but not
limited to, core data, engineering data, well logs, gravity surveys, geochemical
surveys,  paleontological  data or any other data  currently in each  respective
party's files pertaining to the Contract Area.  Access,  for the purposes hereof
shall  include  the right for SPR  and/or any member of either the FINA GROUP or
the FRONTIER  GROUP,  at their own expense,  to make copies of the other's data.
SPR,  nor any party of either the FINA  GROUP nor the  FRONTIER  GROUP  shall be
required,   however,  to  show  any  interpretive  geological,   geophysical  or
engineering data to the other, except that data necessary to support or required
to propose the  designation  of a Prospect  Area within the  Contract  Area,  as
hereinafter provided.

     6.7  Confidential  Technical  Data.  Technical  data  which  is  restricted
pursuant  to the  terms of an  agreement  of  confidentiality  shall not be made
available under the terms of this Article 6.

     6.8 Lost Licensing  Agreements.  In the event license to any data cannot be
found by the party owning the data, the party owning the data shall use its best
efforts  to  obtain  a copy of the  license  for the  data,  but in the  event a
licensing  agreement as to certain data cannot be located,  or obtained  without
repurchasing  the  data,  the  party in  possession  of the  data  may  withhold
disclosure of such data, at its sole option.

                                    ARTICLE 7

                          OPTION AND AGREEMENT TO LEASE
                     AGREEMENT TO DELIVER WORKING INTERESTS

     7.1 Lease  Option.  At any time during the period  beginning  on the date a
fully  processed  data set covering the Contract Area and the 3-D Survey License
Area is delivered to each and every party hereto and ending with the termination
of  this  Agreement,  the  FRONTIER  GROUP  shall  have  the  right  and  option
("Option"),  but not the obligation, to obtain from FINA a lease covering all or
part of the FINA Fee Lands (excluding any Initially  Excluded Lands). The Option
shall give such rights to acquire  such  lease(s) to the  FRONTIER  GROUP to the
exclusion of any person or entity not a party to this  Agreement.  The leasehold
interest granted pursuant to such leases(s) shall be limited to that working


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interest  set forth for the  FRONTIER  GROUP on Exhibit "B"  hereto.  The Option
shall be exercised by giving  written notice to FINA (with a copy to SPR) at the
address set forth herein.  In this notice the FRONTIER  GROUP shall identify the
acreage  to be leased by legal  description  and tender a check in the amount of
$150 per net mineral acre selected.  The lease term shall be for three (3) years
(with annual rentals of $150 per net mineral acre) and the  landowner's  royalty
reserved  unto FINA shall be 33.33% of 8/8ths.  Within thirty days after receipt
of such  notice,  FINA  agrees to execute  and  deliver to the  FRONTIER  GROUP,
jointly,  one  original of an oil and gas lease  covering  the acreage  selected
identical in form to the lease attached hereto and made a part hereof as Exhibit
"C", and containing the identical terms and conditions as set forth therein.

     7.2 Agreement to Deliver Working  Interest in Leases,  Options to Lease and
Oil and Gas  Interests.  FINA  shall give  notice to SPR and each  member of the
FRONTIER GROUP at least 72 hours prior to the time the fully  processed data set
covering the Contract Area and the 3-D Survey  License Area will be delivered to
SPR and the FRONTIER  GROUP.  Simultaneously  with delivery by the FINA GROUP to
SPR and the FRONTIER GROUP of the fully processed data set covering the Contract
Area and the 3-D Survey  License Area,  the FRONTIER  GROUP shall deliver to SPR
and the FINA GROUP, jointly, at no cost to SPR and the FINA GROUP, an assignment
duly  executed and in the form  attached  hereto as Exhibit "G", of the FRONTIER
GROUP's interest in and to the FRONTIER GROUP Leases (hereinafter referred to as
the  "Assignment");  limited  however,  to the interest in such  FRONTIER  GROUP
Leases  as set forth  for SPR and the FINA  GROUP on  Exhibit  "B"  hereto.  The
undivided interests in the Leases to be conveyed to SPR and the FINA GROUP shall
have  no  burdens  other  than  landowner  royalty  and the  overriding  royalty
interests to be granted to Laurent Oil & Gas, Inc.  ("Laurent") and Leo R. Bader
("Bader")  pursuant to that certain letter agreement dated April 27, 1995 by and
among Frontier,  Polaris, Laurent and Bader as amended dated August 14,1996 (the
"Laurent  Agreement")  (which  shall  not  exceed  3% on  Leases  with  lessor's
royalties  of 25% or less,  or 1.5% on Leases with  lessor's  royalty of greater
than 25%, or 1.5% on Leases acquired by farm out or exploration agreement) to be
borne by SPR and the members of the FINA GROUP in proportion to their respective
working  interests.  Burdens on such Leases in excess of land owner  royalty and
overrides under the Laurent  Agreement shall be the sole  responsibility  of the
members of the FRONTIER GROUP creating said excess burden.  All obligations owed
to  Laurent or Bader  pursuant  to any  agreement  (including  specifically  but
without limitation the Laurent Agreement) to permit the acquisition by either or
both of them of  interests  in  leasehold  or  other  interests  (not  including
overriding  royalty interests) after completion of the 3-D Survey shall be borne
entirely by the  FRONTIER  GROUP,  and the  members  thereof  shall  jointly and
severally  indemnify and hold harmless SPR and each and every member of the FINA
GROUP from and against  any  reduction  in  interest  or any other  loss,  cost,
expense or claim whatsoever arising in connection therewith.

     7.3  Agreement  to Assign  Options and the Rights to  Options.  Included on
Exhibit A-1 attached hereto is a list of all of the options to lease held by the
FRONTIER GROUP. Exercise by the FRONTIER GROUP of any options to lease, owned by
any member of the FRONTIER  GROUP within the  Contract  Area,  shall be the sole
responsibility  of the FRONTIER  GROUP.  Any and all leases so acquired shall be
assigned by the FRONTIER  GROUP to SPR and the FINA GROUP within three  business
days after receipt  thereof by such member(s) of the FRONTIER GROUP, as provided
herein,  and  neither SPR nor the FINA GROUP shall be charged for any portion of
the costs or expense  incurred in connection  with the  acquisition  or exercise
thereof.  Should any member of the FRONTIER  GROUP elect to not exercise its pro
rata portion of any part of such option,  the remaining  members of the FRONTIER
GROUP will have the right to acquire said  interest.  Should the FRONTIER  GROUP
collectively  elect, for any reason, not to exercise all or any pro rata portion
of any part of such  options  as  contemplated  herein,  then it  shall  deliver
written  notice of its  election  not to  exercise to SPR and each member of the
FINA GROUP as soon as possible, but in no event less than ten (10) business days
prior to the  expiration of the  applicable  option.  SPR, the FINA GROUP or any
member  thereof,  would have the option,  but not  obligation,  to exercise  the
remaining pro rata portion of any part of said options in accordance  with their
terms at its sole cost and expense.  The FRONTIER GROUP will take such action as
is necessary to permit the timely  exercise of such option by SPR and any member
in the FINA GROUP  desiring  to exercise  same.  In the event any such option is
exercised by any member of the FINA GROUP, each non-participating  member of the
FRONTIER GROUP shall forfeit any interest in and to any leases acquired pursuant
to such options.  After  delivery of the fully  processed  data set covering the
Contract  Area and the 3-D Survey  License  Area to the  FRONTIER  GROUP and the
assignment  of the  leasehold  interest as  provided  herein to SPR and the FINA
GROUP,  any delay  rentals  approved  by all  parties  to be paid on the  leases
assigned from the FRONTIER  GROUP to SPR and the FINA GROUP shall be paid 16.67%
by SPR, 33.33% by the FINA GROUP and fifty percent (50%) by the FRONTIER GROUP


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<PAGE>
notwithstanding  the Working Interest  Ownership in such Lease(s) for each group
as set out in Exhibit  "B".  Should any  party(ies)  hereto elect not to pay any
delay rental  obligation,  then the parties consenting to pay such rentals shall
bear such costs proportionately, and receive the benefit thereof proportionately
and all  non-participating  parties  shall  forfeit  any and all  rights  to the
leases, lands and interests affected thereby.

                                    ARTICLE 8

                                 SEISMIC PROGRAM

     8.1 Geophysical Permit. During the term of this Agreement, SPR and the FINA
GROUP at their sole cost,  risk and expense,  shall have the exclusive  right to
conduct seismic exploration operations within the Contract Area. At such time as
requested by FINA,  the FRONTIER  GROUP shall  deliver at no cost to SPR and the
FINA GROUP all necessary permits  pertaining to lands, Oil and Gas Leases or Oil
and Gas  Interests  owned or controlled by each and every member of the FRONTIER
GROUP as  required  by SPR and the FINA GROUP or their  contractor,  in the form
attached hereto as Exhibit "H", to enable SPR and the FINA GROUP to conduct said
seismic exploration operations.

     8.2 3-D Survey. As primary consideration for the FRONTIER GROUP's execution
of this Agreement and in consideration for the Assignment of Leasehold interests
described  in  Article 7 hereof,  SPR and the FINA  GROUP  agrees to pursue  the
acquisition  of a 3-D seismic  survey (the "3-D  Survey")  covering the Contract
Area,  using the parameters set forth on Exhibit "F" attached  hereto and made a
part  hereof,  with the  intent  and in such  manner  and to such  extent  as to
properly image substantially all horizons down to and including the Tex "W" Sand
Series in the subsurface of the Contract  Area.  FINA shall be designated as the
Operator of the seismic  operations  and shall  conduct the 3-D Survey in a good
and workmanlike  manner,  but neither FINA, SPR nor any member of the FINA GROUP
shall  have  any  liability  to the  FRONTIER  GROUP  for  losses  sustained  or
liabilities  incurred  except  such as may result from the gross  negligence  or
willful  misconduct of SPR or such member of the FINA GROUP.  Upon completion of
the 3-D Survey and  receipt  of a fully  processed  data set of same SPR and the
FINA GROUP shall make  available on the same day it is delivered to or otherwise
available to SPR and any member of the FINA GROUP, to the FRONTIER GROUP a fully
processed  data set  covering  both the  Contract  Area  and the  adjacent  area
outlined  in green on Exhibit  "A" and  designated  as the "3-D  Survey  License
Area." Said data set shall include full fold data over the Contract Area and the
3-D Survey  License Area to the extent SPR and the FINA GROUP has full fold data
available.  The associated  costs of the entire 3-D Survey shall be borne solely
by SPR and the FINA  GROUP.  Prior to  delivery  of said  data set as set  forth
herein,  the FINA GROUP shall make periodic reports,  not less than monthly,  to
SPR and the  Designated  Member of the FRONTIER  GROUP of the status of said 3-D
Survey.

     Said  periodic  reports  shall  include  (i)  weekly  reports  on all field
     operations  within the Contract Area and the 3-D Survey License Area. These
     reports should  include status and updates of permits,  leases and options,
     and maps with progress for surveying,  drilling,  layout and shooting,  and
     other  any  relevant  information;  (ii)  estimates  for  commencement  and
     completion  of  various  activities  within the  Contract  Area and the 3-D
     Survey License Area.  These estimates should include  surveying,  drilling,
     shooting, and processing and should be updated no less frequently than once
     a month;  (iii) daily  progress  and  quality  control  reports  during the
     shooting phase;  and (iv) processing flow chart and parameter  testing with
     input to parameter  selection  and  processing in the Contract Area and 3-D
     Survey License Area to be provided by the FRONTIER GROUP.

     8.3 Separate Processing Option. Subject to the prior written consent of the
FINA GROUP,  the FRONTIER GROUP may, at its sole option and sole cost,  elect to
have that portion of the 3-D Survey  covering  the Contract  Area and/or the 3-D
Survey  License  Area  processed  (or   reprocessed  or  both)   separately  and
independently  from the  entire  3-D  Survey by a third  party  recognized  as a
commercial seismic processor  acceptable to SPR and the FINA GROUP provided that
the separate processing can be accomplished without interference or delay to the
processing activities of SPR and the FINA GROUP. If the FRONTIER GROUP so elects
to separately process (or reprocess) such partial information,  and the FRONTIER
GROUP  receives said processed (or  reprocessed)  data set prior to the time SPR
and the FINA GROUP  receives an initially  processed data set, over the Contract
Area,  then the FRONTIER  GROUP  warrants  that it shall  deliver or cause to be
delivered a complete and fully  processed copy of the  separately  processed (or
reprocessed)  data set to SPR and each member of the FINA  GROUP,  at no cost to


                                        7
<PAGE>
SPR or the FINA GROUP, by the accepted  processor on the same day the separately
processed (or reprocessed) data set is first delivered or otherwise available to
any member of the FRONTIER GROUP. At such time as SPR and the FINA GROUP receive
a processed data set over the Contract Area, the FRONTIER GROUP's  obligation to
deliver copies of its processed (or reprocessed) data set over the Contract Area
to SPR and the FINA GROUP shall cease.

     8 .4 Acquisition of Other Necessary Geophysical Permits. FINA, as Operator,
shall  proceed  with  diligent  efforts to acquire the  necessary  permits  from
adjacent and  surrounding  land owners to legally shoot the 3-D Survey and, once
such permits are  obtained,  to complete  said survey.  In the event SPR and the
FINA GROUP  cannot  acquire and process the 3-D Survey  within 270 days from the
Effective Date of this Agreement, then the following options shall apply:

     (A) If at the end of the 270 day period a seismic  crew is in the  Contract
     Area  diligently  acquiring  3-D seismic  data then the time period  within
     which the data shall be completed and delivered  shall be extended for such
     time as is  necessary  in order for FINA to acquire and process  said data,
     provided that  operations  for such  acquisition  and  processing  shall be
     continued with all due diligence and without material interruption; or

     (B) If at the end of the 270 day period a crew is not in the Contract  Area
     acquiring 3-D seismic data and its failure to do so is not caused  directly
     or indirectly or arising out of or in connection with the fault,  action or
     inaction by any member of the FRONTIER  GROUP,  then this  Agreement  shall
     terminate and SPR, the FINA GROUP and the FRONTIER GROUP shall cross-assign
     any and all  permits  which they may have (or in the case of FINA Fee Lands
     said  permits  shall be granted) at that time to acquire 3-D on lands owned
     or controlled by such groups within the Contract Area; or

     (C) If the  failure to have the 3-D seismic  data  acquired  and  processed
     within the 270 day period is attributable in any manner,  whether  directly
     or  indirectly  or  arising  out of or in  connection  with some  action or
     inaction or fault of any member of the FRONTIER GROUP, then the time period
     within  which FINA may acquire  and  process the 3-D seismic  data shall be
     automatically  extended  to the length of time  required  to  complete  any
     operation as the result of any delay by the FRONTIER GROUP; or

     (D) If the 3-D seismic information is not acquired and processed within the
     270 day period and such delays are not  attributable to the fault or action
     or inaction of any member of the FRONTIER  GROUP,  the parties may agree by
     mutual  consent to extend the 270 day  period,  and in such  event,  to the
     extent that the  extension of time requires the  expenditure  of additional
     costs in order to maintain Leasehold interests or options or permits on the
     FRONTIER GROUP leases, then SPR will bear and pay 16.67% and the FINA GROUP
     will bear and pay 33.33% of all such costs, respectively.

     8.5 Ownership of Acquired Data.  Notwithstanding  anything contained herein
to the  contrary,  no seismic  data within the  Contract  Area or the 3-D Survey
License Area  acquired  pursuant to this  Agreement  shall be sold,  licensed or
otherwise  made  available to any person or entity not a party to this Agreement
during the term of this Agreement; provided however, regardless of any provision
of this Agreement to the contrary,  that the FRONTIER GROUP shall have the right
to make available to Laurent Oil & Gas, Inc.  ("Laurent")  such 3-D seismic data
as is called for in the Laurent Agreement under terms as set forth therein,  and
in the event Laurent exercises his look-back right (as said rights are set forth
in the Laurent  Agreement) as regards to the FRONTIER  GROUP's  interest herein,
Laurent will have pro rata rights to the 3-D data set forth in this Agreement as
if Laurent were part of the FRONTIER GROUP and a party hereto.  All seismic data
and all information  related thereto within the Contract Area and the 3-D Survey
License Area acquired pursuant to this Agreement and any and all proceeds, value
and/or other consideration  arising therefrom,  regardless of the selling party,
shall be owned jointly  twenty-five percent (25%) by SPR, fifty percent (50%) by
the FINA GROUP and twenty-five  percent (25%) by the FRONTIER GROUP as set forth
proportionateley  on Exhibit "B-1" hereto,  from the Effective Date through such
time as SPR and the FINA GROUP have  recouped  all costs they have  incurred  in
connection  with  obtaining such seismic data within the area required to obtain
full fold  coverage  of the  Contract  Area.  After SPR and the FINA  GROUP have
recouped all of such costs,  said seismic data and all benefits  and/or proceeds
derived  therefrom,  shall be jointly  owned  16.67% by SPR,  33.33% by the FINA


                                        8
<PAGE>
GROUP and fifty percent (50%) by the FRONTIER GROUP.

     8.6 Allocation of Seismic Data Sales Proceeds. Following the termination of
this Agreement all seismic data and all  information  related thereto within the
Contract Area acquired  pursuant to this Agreement shall be and remain the joint
property  of SPR,  the FINA  GROUP  and the  FRONTIER  GROUP,  and shall be kept
confidential  and shall not be  licensed,  sold,  published  or disclosed to any
third party, without the prior written approval of a group of SPR and members of
the FINA GROUP and the FRONTIER GROUP,  then holding seventy five percent 75% or
more of the total seismic data ownership as set forth on Exhibit "B-1". If after
the  termination of this Agreement,  the parties holding the requisite  interest
agree to  license  all or a portion  of the  data,  then any  monies or  benefit
received  from the  marketing of said data (after  approval)  shall be shared by
SPR,  the FINA  GROUP  and the  FRONTIER  GROUP on the  basis of their  interest
therein  at the time of such  sale or  license.  Notwithstanding  any  provision
hereof to the  contrary,  SPR and the FINA GROUP  shall be the owner of the data
within the 3-D Survey  License Area,  but the FRONTIER  GROUP shall be granted a
license to use such data.  Said license shall be in the form attached  hereto as
Exhibit  "D".  All monies and other  consideration  due any party hereto for the
sale or other  disposition  of such seismic data shall be paid to the applicable
parties within ten (10) days of the selling party's receipt thereof.

     8.7 Applicability After Termination.  The provisions of Section 8.5 and 8.6
shall  survive  and  remain  valid and  binding  following  termination  of this
Agreement.

                                    ARTICLE 9

                    LEASE ACQUISITION AND DRILLING OPERATIONS

     9.1 AMI. Should any party to this Agreement  obtain or have the opportunity
to obtain an interest in minerals,  an oil and gas lease,  an option to lease or
contractual  right  to  explore  for  and/or  produce  oil  and  gas or  similar
interest(s) within the Contract Area (the "Available Interests") which interests
are not  FRONTIER  GROUP Leases or FINA GROUP Leases then SPR and each member of
the FINA GROUP and the FRONTIER  GROUP shall have the option to  participate  in
the  acquisition  of the  Available  Interests  as to SPR's  and  each  member's
respective share of its group's  interest(s) as set forth in Exhibit "B" hereto.
In such event,  the party  acquiring  or having the  opportunity  to acquire the
Available Interests shall offer in writing, as soon as possible but in any event
within ten (10) business days of acquiring  such Available  Interest(s),  to all
other parties hereto, the option to participate in such acquisition. The cost of
any such  acquisition  shall be borne fifty percent (50%) by the FRONTIER GROUP,
16.67% by SPR and 33.33% by the FINA  GROUP,  notwithstanding  the  division  of
working  interest  for each party or group as set forth on Exhibit  "B". SPR and
each group shall have thirty  (30) days after  receipt of written  notice of the
right to participate in the acquisition of the Available Interests (which notice
shall  include  all  information  relevant  to  such  determination  such as the
acquisition cost and any obligations involved),  in which to elect in writing to
purchase  all or part of its  proportionate  share  of the  Available  Interest.
Should any party of either group elect not to participate in the  acquisition of
its proportionate share of the Available Interest, then such party's share shall
be made available first to the other members of the group of which such party is
a member. To the extent that the remaining members of such group do not elect to
acquire  the  interest  of  any  of  its  non-participating  members,  then  the
Designated Member of such group shall give written notice to SPR and each of the
members of the other group of the  availability  of such  interest.  Such notice
shall be given at the same time as the election to  participate  for all or part
of the  available  interest is due to be delivered  pursuant to this  paragraph.
Should SPR elect not to  participate  in the  acquisition  of its  proportionate
share of the Available  Interest,  then SPR shall give written notice to each of
the members of the FINA GROUP and the FRONTIER GROUP of the  availability to its
interest.

     9.2 Election Notice The election by SPR and/or either group to purchase any
share of the Available  Interest shall be evidenced by a timely written election
which shall state specifically  whether SPR or the group is taking all or only a
part  (and if only a part,  the  percentage  being  taken)  of its  share of the
Available Interest, which election shall be submitted with payment by SPR or the
Designated  Member of such group of its  proportionate  share of the acquisition
cost (which shall be 16.67% to SPR,  33.33% to the FINA GROUP and fifty  percent
(50%) to the FRONTIER  GROUP if SPR,  the FINA GROUP  and/or the FRONTIER  GROUP
take  their  entire  share of the  Available  Interest).  Failure  by SPR or the
Designated Member of the applicable group to timely respond or make the required
payment  shall be deemed an election by SPR and all members of such group not to
participate. Any party hereto receiving notice of the availability of a share


                                        9
<PAGE>
of the Available  Interest  which has been declined by all of the members of the
other group (the  "Additional  Interest") shall have five (5) days after receipt
of such  notice  within  which to elect  whether or not to  participate  for its
pro-rata  share of the  Additional  Interest  by  giving  written  notice of its
election to the SPR and  Designated  Member of each  group.  In the event that a
party hereto  elects to acquire a portion of the  Additional  Interest then such
acquiring  party shall pay a share of the costs  attributable  to that  interest
equal to the costs which would have been paid had the interest  been acquired by
the party to whom it was initially offered. In the event a well is being drilled
pursuant to the terms of a JOA whose  contract  area includes all or part of the
Available  Interest,  the time period for the initial election and payment shall
be five (5) working days from the receipt of the pertinent information,  instead
of the twenty days previously set out above. In the event SPR and/or both groups
acquire  their  proportionate  share of the  Available  Interest,  said interest
immediately  and  automatically  shall become  subject to this Agreement and any
existing JOA's, as applicable, for all purposes. The Designated Members shall be
responsible  for the diligent and timely  communication  of all  information and
election notices to the members of their group, SPR and the Designated Member of
the other group.

     9.3  Designation  of a Prospect  Area,  Well  Proposals  and  Elections For
Participation.  At any time after  delivery to all of the parties  hereto of the
fully  processed  data  set  covering  the  Contract  Area,  any  party  to this
Agreement,  who  owns a then  current  working  interest  therein,  may  propose
hereunder the  designation  of a Prospect Area within the Contract Area, and the
drilling of a well within such Prospect Area ("Initial Test Well"). For purposes
hereof "Prospect Area" shall mean a specified  geographical  area under which is
thought  to exist  one or more  subsurface  or  geological  features  which  the
parties, through geological interpretation,  believe to be capable of structural
or  stratigraphic  trapping  of oil and gas in  economic  quantities.  Any given
Prospect  Area shall  represent the parties' best efforts to identify and define
the surface area encompassing the entirety of all reservoirs reasonably expected
to be proven by the  wellbore of the Initial  Test Well.  The  designation  of a
Prospect Area shall be evidenced in writing and may be changed  thereafter based
on new information or revisions of  interpretations of old information and/or by
actions of a governing  body having or  asserting  jurisdiction.  The  proposing
party  shall  notify  each party  hereto in writing of its  proposal  and call a
meeting of the  parties  within ten (10) days  after said  notification.  In the
meeting the  proposing  party shall present to SPR and the members of each group
all relevant  data to support its proposed  designation  of a Prospect  Area and
drilling of the Initial Test Well and will include in its presentation the depth
to be drilled, the primary objective and all other horizons likely to be tested,
detail estimated  drilling and completion costs and a drilling  prognosis of the
proposed  Initial Test Well. The party  proposing the  designation of a Prospect
Area shall attempt in good faith to obtain the approval of such Prospect Area by
all of the parties to this Agreement.  In the event all the parties do not agree
to the designation of the applicable  reservoir  limits as proposed in any given
Prospect  Area,  then the vote of the parties  holding  cumulatively  75% of the
working interest in all depth through the base of the Duval Sand as set forth at
Exhibit  "B"  hereto as to those  depths,  and the vote of the  parties  holding
cumulatively 75% of all the working interests in all depths from the base of the
Duval Sand  through  the base of the  DuLarge  Sand as set forth at Exhibit  "B"
hereto as to those depths, and the vote of the parties holding  cumulatively 75%
of all of the working  interest in all depths below the base of the DuLarge Sand
as set forth in Exhibit "B" hereto as to those  depths,  as regards each of such
reservoirs  reasonably expected to be proven by the wellbore of the Initial Test
Well, shall be deemed binding on all of the parties hereto as to the designation
of each such reservoir to be established  within the Prospect Area. The Prospect
Area shall encompass the largest overall reservoir limits within its confines.

     There shall be no more than three  Initial Test Wells  proposed or drilling
to casing  point  election  within  the  Contract  Area at a time.  Of the three
Initial Test Wells which may be proposed or drilling  simultaneously,  there may
be no more than (i) two (2)  proposed  or  drilling to a depth above the base of
the DuLarge  Sand,  or (ii) two (2) below the base of the DuLarge Sand such that
the  parties  shall have the right to propose or drill one  shallow  well or one
deep well, as applicable,  at all times. In addition thereto,  to the extent the
FRONTIER  GROUP  proposes  to drill any  wells to the base of the Duval  Sand or
shallower,  as set forth at Exhibit  "B",  solely on FRONTIER  GROUP  Leases and
solely  within the areas  colored in green on the  attached  Exhibit "A", it may
propose  and drill any number of such wells and such wells  shall not be counted
to reduce the number of wells drilled  pursuant to this  provision.  Inasmuch as
SPR or any member of the FINA GROUP  proposes  to drill any well on the FINA Fee
Lands from the base of the Duval Sand to all deeper  depths and/or on FINA GROUP
leases to all depths, it may propose and drill any number of such wells and such
wells  shall not be counted to reduce the number of wells  drilled  pursuant  to
this provision.  Any proposal made in  contravention  of this provision shall be
void and require no response by any party.

                                       10
<PAGE>
     9.4 Election Options. The parties not proposing the drilling of the Initial
Test Well shall have the following options, which options must be elected within
the time notices contained in Article 12:

A.   (i) elect not to  participate in the Initial Test Well as to any depth ("No
         Participation"),

          i)   elect to  participate  in the Initial Test Well in the manner and
               to the total depth proposed ("Full Participation"),

          ii)  elect to limit its  agreement  for  participation  to a shallower
               objective (the  "Alternate  Depth") than the total depth proposal
               ("Depth Limited Participation") or

          iii) propose  that the  Initial  Test Well be drilled to a depth below
               the depth originally  proposed  ("Proposal to Deepen");  provided
               however,  that  any  well  proposed  to be  drilled  to a  proven
               underdeveloped  location, which location is located solely within
               the areas colored in green on Exhibit "A" attached hereto,  shall
               not be subject to any such proposals to deepen.

     The  consequences  corresponding  to the  election  of each of the  options
described in Article 9.4A. above by any party(ies) or either group hereto are as
follows:

B.    (i) No Participation. In the event any party elects No Participation in
          the Initial  Test  Well in any  Prospect  Area  and the  participating
          parties proceed to drill such Initial Test Well, the non-participating
          party shall be deemed to have farmed out to the remaining  parties its
          interest in the reservoir(s) that are proven, by the Initial Test Well
          or the stratigraphic equivalent  thereof,  and that are within the
          applicable Prospect Area, on the terms set forth in Section 9.5 below.

     (ii) Full Participation. If the parties elect Full Participation each party
          shall  participate in the Initial Test Well as proposed and shall bear
          their  respective  share of the cost  thereof.  The parties shall also
          enter into a mutually  agreeable form of operating  agreement for such
          well and if no agreement can be reached the operating  agreement  will
          be in the form of the JOA.

     (iii)Depth Limited  Participation.  If any non-proposing party elects Depth
          Limited Participation (the "Uphole  Participant(s)"),  it shall notify
          the proposing  party of such  election and of the  Alternate  Depth to
          which the Uphole  Participant has elected to  participate.  The Uphole
          Participat   by  making   such   limited   election   and  paying  its
          proportionate  share of drilling costs to the Alternate  Depth,  shall
          have  preserved  all of its rights to receive a lease or assignment as
          provided  herein  for all depths  above 100 feet  below the  Alternate
          Depth in the Prospect Area or the  stratigraphic  equivalent  thereof.
          The Uphole Participant will be deemed to have farmed out its interests
          to all depths  deeper than one hundred  (100) feet below the Alternate
          Depth or the stratigraphic  equivalent thereof,  within the Applicable
          Prospect  Area  according to the  provisions  set forth in Section 9.5
          below.

     (iv) Proposal to Deepen.  Any  non-proposing  party(ies) may respond to the
          original  proposal by proposing to drill the well to a depth below the
          depth  originally   proposed  (the  "Downhole   Participant(s)"),   by
          submitting  a proposal for drilling to the deeper depth within the ten
          (10)  business  days of its  receipt  of the  original  proposal.  The
          Proposal  to Deepen  shall be then  deemed a  proposal  made under and
          subject to the time  periods  and other  provisions  set forth in this
          Article  9 and  in  Article  12.  The  Proposal  to  Deepen  shall  be
          considered,  and  operations  in  furtherance  thereof  conducted,  in
          priority to the original proposal.

     9.5 Farm out Terms.  In the event any party  shall be deemed to have farmed
out  ("Farmor")  to the other  Parties  ("Farmee")  its working  interest in any
reservoir(s)  within the Prospect Area, the interest farmed out shall be limited
to rights which are:

     1.   within the Prospect Area, and
     2.   limited to rights  from the surface to a depth 100 feet below the base
          of the deepest commercially


                                       11
<PAGE>
          productive reservoir in the Initial Test Well, and
     3.   limited to interests  which appear  productive  in the wellbore of the
          Initial Test Well, and
     4.   limited geographically to locations classified "proven" by the Initial
          Test Well  pursuant to  generally  accepted  engineering  standards as
          accepted by the United States  Securities and Exchange  Commission for
          publicly reporting companies.

     To the extent  interests are thereby  farmed out the Farmor shall retain an
overriding  royalty  interest in such  reservoir(s)  equal to two percent  (2%),
which retained  interest shall be reduced in the same  proportion as the working
interest  farmed out bears to 100%. In the event the parties  cannot agree as to
which  interests are "proven" by the Initial Test Well, the  consulting  firm of
Ryder Scott Company Petroleum  Engineers of Houston,  Texas shall by retained to
make  such  determination  with the cost  thereof  shared  by the  parties.  The
decision  of Ryder  Scott  Company  Petroleum  Engineers  shall be  accepted  as
conclusive by all of the parties hereto. At Payout of the Initial Test Well, the
Farmor shall have the option to convert its retained overriding royalty interest
in such well to a  working  interest  in the  applicable  reservoir(s)  equal to
thirty percent (30%) of the working interest  originally owned by the Farmor and
farmed out  hereunder.  In the event the farmor elects to convert its overriding
royalty  interest  in such well to a working  interest at Payout,  said  working
interest shall be subject to a mutually  agreeable  form of operating  agreement
and if no agreement can be reached the operating  agreement shall be in the form
of the JOA.  However,  the Farmor shall have the option to  participate  for its
after  Payout  working  interest  in such  farmed out  reservoir(s)  within such
Prospect Area in all wells proposed after the Initial Test Well in said Prospect
Area is spud,  regardless  of whether  Payout in the  Initial  Test Well in such
Prospect Area has been achieved and whether or not Farmor has elected to convert
its overriding royalty interest to a working interest in the Initial Test Well.

     9.6 Elections on a Group Basis. If any member(s) in any group elects not to
participate, then the interest of such non-participating member shall be offered
first to the other members of its group in accordance with agreements among such
members.  If the remaining member(s) of such group do not assume the interest of
the  declining  member in their group then the  Designated  Member of such group
shall  send  written  notice to SPR and all of the  members  of the other  group
stating that such  interest is available.  The proposing  party or its designee,
provided that the proposing  party owns a working  interest at the deepest depth
proposed to be drilled to in such well,  regardless of whether the well is to be
or actually is  completed at such depth equal to or greater than any other party
at such deepest depth, shall  automatically be designated as the Operator of the
Prospect  Area for said Initial Test Well and the  applicable  Prospect Area for
all drilling and production  operations therein.  Should the proposing party not
own sufficient working interest to automatically  qualify as Operator,  then the
Downhole Participants in said Initial Test Well shall elect an Operator for said
well and Prospect  Area.  For the  purposes of this  provision as it pertains to
wells  drilled on FRONTIER  GROUP Leases ONLY,  the parties  agree that SPR or a
member of the FINA GROUP  shall  always be  designated  as  Operator of any well
drilled  to or below  the base of the  DuLarge  Sand,  and that a member  of the
FRONTIER  GROUP shall always be  designated  as Operator of all wells drilled to
and  completed at or above the base of the DuLarge Sand, as described at Exhibit
"B"  hereto,  unless  otherwise  agreed to the  contrary  in  writing by all the
participating parties in said well.

     9.7 Payments.  In the event a Party elects Depth Limited  Participation the
Operator  shall bill and the Uphole  Participant  shall pay pursuant to the JOA,
its share of the costs which would have been  necessary  to drill,  and plug and
abandon  the Initial  Test Well to the  Alternate  Depth only,  on a stand alone
basis ("Base Costs") for drilling the well to the Alternate  Depth.  If the well
is plugged and abandoned,  upon completion of such activities the Operator shall
bill and the  Uphole  Participant  shall pay or  receive a credit as  applicable
pursuant to the JOA,  for its actual  share of the Base Costs for  plugging  and
abandonment.  Any costs whatsoever incurred over Base Costs, including by way of
example but without  limitation,  costs  incurred for additional  drilling,  for
different or  additional  above ground or downhole  equipment,  for sidetrack or
other  drilling or equipment  problems or for  additional  time, any of which is
incurred due to drilling  beyond the Alternate  Depth shall be borne one hundred
percent (100%) by Downhole Participants.

     For all  purposed of this  Article 9, the  Operator  shall  within five (5)
business  days  from  the  filing  of a  completion  report  with  the  State of
Louisiana,  reimburse  the  Uphole  Participants  their  proportionate  share of
drilling costs to the Alternate Depth in a deepened well if and when any horizon
is completed in such  deepened  well as a commercial  producer at a level deeper
than the level at which the Uphole Participants own a working interest. Any


                                       12
<PAGE>
Uphole  Participant  shall have the right to  propose a well(s)  within the unit
boundary of the completed deepened well to test a shallower horizon to which its
participation had been limited (the "Accelerated  Well"), but only to the extent
that the Uphole Participants  participating in such Accelerated Well(s) agree to
and  pay for  the  Downhole  Participants'  (participating  in such  Accelerated
Well(s)) proportionate share of drilling costs to the casing point election. All
Downhole  Participants  in the deepened well shall have the right to participate
in such Accelerated  Well(s).  Should the Uphole  Participants  participating in
such an  Accelerated  Well(s)  actually  drill  and  pay  for the  participating
Downhole Participants' share of said drilling costs, then (a) said participating
Uphole  Participants  shall not be required to  contribute  or  reimburse to any
Downhole  Participant  any  costs  for  the  deepened  well,  except  for  costs
associated  with a  completion  attempt(s)  to which said  participating  Uphole
Participants  consent to and which are at or above the deepest  horizon in which
they own a working interest, and (b) the Downhole Participants  participating in
an  Accelerated  Well shall not be required to  contribute  or  reimburse to the
Uphole  Participants  any  costs  for the  Accelerated  Well,  except  for costs
associated  with a completion  attempt(s) to which said  participating  Downhole
Participants consent to in such Accelerated Well.

     If a deepened well is  subsequently  plugged back and completed at or above
the Alternate  Depth,  the Operator shall bill, and all Uphole  Participants who
have not participated in any Accelerated Well(s) within the unit boundary of the
completed  deepened well shall pay, their share of the calculated Base Costs for
(i) the drilling to the  Alternate  Depth and (ii)  (subject to the casing point
election in the  Operating  Agreement)  completion  of such deepened well at the
shallower  recompleted depth. In such instance,  the calculated Base Costs shall
be equal to the costs which would have been  incurred  had the well been drilled
and  completed  at the  shallower  recompleted  depth  at the  time the well was
originally  drilled.  One hundred  percent (100%) of such  reimbursed Base Costs
shall be allocated and paid by the Operator of the deepened well to the Downhole
Participants in said deepened well who have not  participated in any Accelerated
Well within the unit boundary of the deepened  well,  prorata based on the ratio
that  each  such  Downhole  Participant's  working  interest  bears to the total
working interests of all such Downhole Participants who have not participated in
any  Accelerated  Well.  To the extent  that all  Downhole  Participants  in the
deepened well have  participated in one or more  Accelerated  Well(s) within the
unit  boundary of the deepened  well,  then one hundred  percent  (100%) of such
reimbursed  Base Costs shall be  allocated  proportionateley  among the Downhole
Participants in the deepened well based on their working interests.

     9.8 Joint Operating Agreements.  Any and all operations for the drilling of
the Initial  Test Well which are not  specifically  covered by the terms of this
Agreement,  and any and all  operations in a Prospect Area (or the contract area
under a specific JOA)  subsequent to the drilling of the Initial Test Well shall
be performed pursuant to the terms of the applicable JOA. Each of the parties to
this  Agreement  who  participated  in any operation in a well or wells within a
Prospect  Area  shall also be parties to the  applicable  JOA.  Each  Designated
Member  shall  provide a  designation  of interest  to each other  party  hereto
outlining the percentage which each member in the Designated Member's respective
group shall participate in any particular  ongoing or proposed operation at such
time as said  operations(s)  are proposed.  In addition to the other  provisions
which may be  contained  in each JOA  which is  entered  into or made  effective
pursuant  to this  Agreement,  it shall  also  contain  restrictions  on certain
drilling  activities  following  the  drilling  of a well in a Prospect  Area as
follows.  The JOA shall have no  restriction  on the number of wells,  reworking
operations,  completion  or other  operations  which may be  proposed at any one
time.

                                   ARTICLE 10

                           RELATIONSHIP OF THE PARTIES

     Except  as  expressly  stated  otherwise   herein,   the  rights,   duties,
obligations and liabilities of the parties hereunder shall be several, not joint
or  collective.  It is not the purpose or intention of this  Agreement to create
any mining partnership, commercial partnership or other partnership relation and
none shall be  inferred  from the  agreement  to file an election to be excluded
from the  application  of certain  United States tax laws.  Each party agrees to
elect to be  excluded  from the  application  of  Subchapter  K of  Chapter 1 of
Subtitle A of the Internal Revenue Code of 1954, and all amendments thereto.


                                       13
<PAGE>
                                   ARTICLE 11

                        ASSIGNABILITY AND CONFIDENTIALITY

     11.1 Limited  Assignability.  The rights,  benefits and obligations of this
Agreement  are  exclusive  between  SPR,  the  members of the FINA GROUP and the
members  of the  FRONTIER  GROUP.  SPR and the FINA GROUP  reserve  the right to
approve the  assignment of any interest in the Agreement  from any member of the
FRONTIER GROUP to any other  unrelated party and the FRONTIER GROUP reserves the
same  right to approve  such an  assignment  from any member of the FINA  GROUP.
Neither SPR, nor the FINA GROUP or the FRONTIER  GROUP shall  unreasonably  deny
any request to assign an  interest  to an  unrelated  party,  provided  that the
unrelated  third party is, in the approving  group's sole  opinion,  at least as
financially  capable as the  assigning  party to perform the  obligations  to be
assigned, or if the assignment provides that the assigning party shall remain as
guarantor of it's assignee.  Notwithstanding  the above, SPR and the FINA GROUP,
by  execution of this  Agreement,  consents to any  assignment  from South Coast
Exploration and SOCO Exploration Limited Partnership to Harcor Energy, Inc., and
to any  assignments  and rights the  FRONTIER  GROUP may be  obligated to convey
pursuant to the Laurent Agreement. It being fully understood and agreed that any
assignment from South Coast Exploration, SOCO Exploration Limited Partnership or
the  FRONTIER  GROUP  will  be  made  expressly  subject  to  this  3-D  SEISMIC
PARTICIPATION  AGREEMENT  and will not affect the rights and  interest of SPR or
the FINA GROUP.

     11.2  Confidentiality.  SPR and  each  member  of the  FINA  GROUP  and the
FRONTIER GROUP agree to hold  confidential all information and data arising from
or related to this  Agreement  and the 3-D  Survey,  including  the terms of the
Agreement  itself,  and not to divulge any facts hereof to any unrelated  party,
except as may be  required  to satisfy  any local,  state or federal  government
regulation, or for the business purpose of selling an interest in this Agreement
to an unrelated party. This confidentiality  provision shall extend to all JOA's
covering  the  Contract  Area  and/or any well(s)  drilled  thereon and will not
terminate until the expiration of this Agreement, or the expiration of any lease
granted or acquired  within the  Contract  Area  pursuant  hereto,  whichever is
later.

                                   ARTICLE 12

                                     NOTICE

     Any notices  authorized or required  herein shall be given by the proposing
party to all other parties  hereto and will have an initial  response  period of
thirty  (30)  days from  receipt  of said  notice,  unless  specifically  stated
otherwise herein.  Should the proposing party not receive a timely response from
SPR or the  applicable  Designated  Member  hereto,  then  in  such  event,  the
proposing  party shall notify all other parties hereto that the response  period
shall be extended for an additional  ten (10) day period  allowing SPR or either
group  additional  time to review  or  confer  with its  Designated  Member  and
respond. In the event there is no response delivered to the proposing party by a
non-proposing  party or  Designated  Member  within said ten (10) day  extension
period,  the proposing  party will notify all other parties hereto that a final,
additional  forty-eight  (48) hour  extension  period  will be granted  prior to
deeming any non-responding party(ies) non-consent.  It is expressly acknowledged
that this provision does not apply to notices issued pursuant to any JOA entered
into and effective  pursuant hereto,  in which regard the notice provision shall
be as set forth in said JOA.  The  aforementioned  notice  periods  (thirty (30)
days,  ten (10) days,  and  forty-eight  (48) hours) are not  applicable  to the
notices and/or election periods  described in Sections 1.13, 7.2, 7.3, 8.6, 9.1,
9.2, 9.3, and 9.7 contained herein.

     All notices  hereunder shall be deemed to be properly given, if in writing,
by facsimile transmission, if followed by postpaid registered or certified mail,
or by courier  delivery,  addressed to the respective  party at the addresses as
set forth below,  or such other addresses as they shall  respectively  hereafter
designate in writing, from time to time:

As to the FINA GROUP:                  FINA Oil and Chemical Company
                                       P. O. Box 62102
                                       Houston, Texas 77205-2102
                                             or
                                       14950 Heathrow Forest Parkway
                                       Houston Texas 77032


                                       14
<PAGE>
                                       (713) 986-6000
                                       (713) 986-6736 Fax

As to the FRONTIER GROUP:              Frontier Natural Gas Corporation
                                       9400 North Broadway Extension
                                       Oklahoma City, Oklahoma 73114
                                       (405) 478-4455
                                       (405) 478-4456 Fax

As to the 
SOUTH COAST EXPLORATION COMPANY:       South Coast Exploration Company
                                       Two Post Oak Central
                                       1980 Post Oak Boulevard
                                       Suite 2050
                                       Houston, Texas  77056
                                       (713) 960-1077
                                       (713) 960-1157 Fax

As to the SOCO EXPLORATION L.P.:       Two Post Oak Central
                                       1980 Post Oak Boulevard
                                       Suite 2050
                                       Houston, Texas 77056
                                       (713) 960-1077
                                       (713) 960-1157 Fax

As to the MATAGORDA PRODUCTION COMPANY:Matagorda Production Company
                                       675 Bering Drive, Suite 850
                                       Houston, Texas  77057
                                       (713) 781-4975
                                       (713) 781-1460 Fax

As to the 
POLARIS EXPLORATION CORPORATION:       P. O. Box 2080
                                       Beeville, Texas  78104-2080
                                       (512) 362-2149
                                       (512) 362-1826 Fax

As to the DENBURY MANAGEMENT INC.:     Denbury Management, Inc.
                                       17304 Preston Road, Suite 200
                                       Dallas, TX  75252
                                       (214) 380-1923
                                       (214) 380-6967 Fax

As to the 
SCANA PETROLEUM RESOURCES, INC.:       SCANA Petroleum
                                       Resources, Inc.
                                       1200 Smith Street, Suite 500
                                       Houston, Texas  77002-4308
                                       Attn: President
                                       (713) 658-8585  Phone No.
                                       (713) 658-1825  Fax No.

                                   ARTICLE 13

                                  FORCE MAJEURE


                                       15
<PAGE>
     If any party is rendered  unable,  wholly or in part,  by force  majeure to
carry out its  obligations  under this  Agreement,  other than the obligation to
make money payments,  that party shall give to SPR and the Designated  Member of
each group  prompt  written  notice of the force  majeure with  reasonably  full
particulars  concerning it (who shall each,  in turn,  inform the members of its
group).  Thereupon,  the  obligations of the party giving the notice,  so far as
they are affected by the force majeure, shall be suspended during, but no longer
than, the  continuance  of the force  majeure.  The affected party shall use all
reasonable  diligence  to remove  the force  majeure  situation  as  quickly  as
practicable.  The requirement  that any force majeure shall be remedied with all
reasonable  dispatch shall not require the settlement of strikes,  lockouts,  or
other labor  difficulty by the party involved,  contrary to its wishes;  how all
such  difficulties  shall be handled shall be entirely  within the discretion of
the party concerned.  The term "force majeure", as here employed,  shall mean an
act of God, strike, lockout, or other industrial disturbance,  act of the public
enemy, war, blockade,  public riot, lightening,  fire, storm, flood,  explosion,
governmental action,  governmental delay, restraint or inaction,  unavailability
of equipment,  and any other cause, whether of the kind specifically  enumerated
above or  otherwise,  which is not  reasonably  within the  control of the party
claiming suspension.

                                   ARTICLE 14

                              ENTIRETY OF AGREEMENT

     This Agreement  represents the entire  understanding  and agreement between
SPR, the FINA GROUP,  and the  FRONTIER  GROUP  regarding  the matters set forth
herein and supersedes any and all prior discussions,  proposals,  understandings
agreements  or  representations,  if any, by either  SPR,  the FINA GROUP or the
FRONTIER  GROUP to another.  Notwithstanding  any provision of this Agreement to
the  contrary,  it is  specifically  acknowledged  and  understood  that a Joint
Exploration and Development  Agreement dated March 29, 1995, by and between FINA
and SPR ("FINA/SPR  Agreement") and an Agreement dated May 30, 1996 by and among
FINA, SPR and DENBURY  ("FINA/SPR/DENBURY  Agreement")  also exist.  The parties
further acknowledge and understand that an Exploration  Agreement dated February
19, 1996  between  Polaris  Exploration  Corporation,  South  Coast  Exploration
Company,  SOCO Exploration L.P.,  Frontier Natural Gas Corporation and Matagorda
Production  Company (the "FRONTIER GROUP  Agreement") also exists.  Each of such
agreements  provide for rights and obligations  between and among the respective
parties thereto  related to operations for obtaining 3-D Seismic,  the ownership
of such  information,  the  acquisition and granting of leases or assignments of
interests  in leases or  minerals  and the  participation  in drilling of wells,
which  agreements  cover  acreage  within the  Contract  Area.  This 3-D Seismic
Participation Agreement is not intended in any manner or respect to amend, alter
or  add  to  the   provisions   of  either  the   FINA/SPR   Agreement   or  the
FINA/SPR/DENBURY  Agreement  and  specifically  as  related  to the  rights  and
responsibilities  of the parties to those  agreements,  any conflict between the
terms of either the FINA/SPR  Agreement or the  FINA/SPR/DENBURY  Agreement  and
this Agreement  shall be governed by the terms of the FINA/SPR  Agreement or the
FINA/SPR/DENBURY  Agreement  as  applicable.   This  3-D  Seismic  Participation
Agreement  is not  intended  to  amend,  alter or add to the  provisions  of the
FRONTIER  GROUP'S  Agreement,  and  specifically  as between the parties thereto
their relationship shall be governed thereby to the extent possiblThis Agreement
shall be binding  upon and inure to the benefit of the parties  hereto and their
respective successors and assigns;  provided,  however, nothing herein contained
shall be construed as permitting an assignment  contrary to the foregoing terms,
conditions and provisions of this Agreement.

     IN WITNESS  WHEREOF,  this  agreement  is  executed on this the 20th day of
August, 1996, but effective as of May 30, 1996.

                                    FINA AND CHEMICAL COMPANY

illegible                           BY:  /s/ W. E. Franklin
-------------                          -----------------------------------------
                                       W. E. Franklin
illegible                              Attorney-in-Fact
-------------

                                    SCANA PETROLEUM RESOURCES, INC.

illegible                           BY:  /s/ Jim Cantwell
-------------                          -----------------------------------------
                                         Jim Cantwell
illegible                                President
-------------

                                       16
<PAGE>

                                    DENBURY MANAGEMENT, INC.

illegible                           BY:  /s/ Matthew Deso
-------------                          -----------------------------------------
                                         Matthew Deso
illegible                                Vice President
-------------

                                    FRONTIER NATURAL GAS CORPORATION

ilegible                            BY:  /s/ David W. Berry
--------------                         -----------------------------------------
                                         David W. Berry
illegible                                President
--------------

                                    SOUTH COAST  EXPLORATION COMPANY

illegible                           BY:  /s/  Ron A. Krenzke
--------------                         -----------------------------------------
                                         Ron A. Krenzke
illegible                                President
--------------

                                    SOCO EXPLORATION L.P.

illegible                           BY:  /s/  illegible
--------------                         -----------------------------------------

illegible                                General Partner
--------------

                                    MATAGORDA PRODUCTION COMPANY

illegible                           BY:  /s/ Hershel Ferguson
--------------                         -----------------------------------------
                                         Hershel Ferguson
illegible                                President
--------------

                                    POLARIS EXPLORATION CORPORATION

illegible                           BY:  /s/ illegible
--------------                         -----------------------------------------

illegible                                President
--------------


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