EXHIBIT 10.6

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                                 PROMISSORY NOTE

U.S.$500,000.00                                                    June 26, 2000

         FOR VALUE RECEIVED,  after date,  without grace, in the manner,  on the
dates and in the amounts so herein  stipulated,  the undersigned,  DAVID S. LAWI
("Borrower"),  3 Ramapo Trail,  Harrison, New York 10528, PROMISES TO PAY TO THE
ORDER OF SEITEL, INC., a Delaware corporation ("Lender"),  50 Briar Hollow Lane,
7th Floor, West Building, Houston, Texas 77027, the sum of FIVE HUNDRED THOUSAND
DOLLARS  ($500,000.00)  in lawful money of the United  States of America,  which
shall be legal tender in payment of all debts and dues,  public and private,  at
the time of payment,  and to pay  interest on the unpaid  principal  amount from
date until  maturity at a variable rate of interest  equal to the Prime Rate (as
defined below). This Note is payable as follows:

          $100,000 of the principal and all accrued and unpaid interest shall be
          due and payable on January 2, 2001; and

          This note shall mature on January 2, 2002,  when the entire balance of
          principal and accrued and unpaid interest shall be due and payable.

         It is agreed  that time is of the  essence  of this  agreement.  In the
event of default in the payment of any installment of principal or interest when
due or in the event of any other default  hereunder,  Lender may  accelerate and
declare this Note  immediately due and payable without notice and opportunity to
cure.  Any failure to  exercise  this option  shall not  constitute  a waiver by
Lender of the right to exercise the same at any other time.

         As used herein, the "Prime Rate" shall be the variable interest rate as
in effect from time to time as published in the Wall Street Journal as the prime
rate of interest generally charged by commercial banks.

         In the event of default in the making of any payment  herein  provided,
either of  principal  or  interest,  or in the event this Note is declared  due,
interest  shall accrue at the maximum  non-usurious  rate  permitted by law (the
"Maximum Rate").

         Borrower  hereby  agrees  to  pay  all  expenses  incurred,   including
reasonable  attorneys'  fees,  all of which shall become a part of the principal
hereof,  if this Note is placed in the hands of an attorney for collection or if
collected  by suit  or  through  any  probate,  bankruptcy  or any  other  legal
proceedings.

         Interest  charges will be calculated on amounts  advanced  hereunder on
the  actual  number of days  these  amounts  are  outstanding  on the basis of a
365-day or 366-day  year, as is  applicable.  It is the intention of the parties
hereto to comply with all applicable usury laws; accordingly,  it is agreed that
notwithstanding  any  provision to the  contrary in this Note,  or in any of the
documents  securing  payment  hereof  or  otherwise  relating  hereto,  no  such
provision  shall  require  the payment or permit the  collection  of interest in
excess of the  Maximum  Rate.  If any  excess of  interest  in such  respect  is
provided for, or shall be  adjudicated to be so provided for, in this Note or in
any of the documents securing payment hereof or otherwise relating hereto,  then
in such event (1) the provisions of this paragraph shall govern and control, (2)
neither   Borrower,   endorsers   or   guarantors,   nor  their   heirs,   legal
representatives,  successors  or  assigns  nor any other  party  liable  for the
payment  hereof,  shall be obligated  to pay the amount of such  interest to the
extent that it is in excess of the Maximum  Rate,  (3) any such excess which may
have been collected  shall be either applied as a credit against the then unpaid
principal amount hereof or refunded to Borrower,  and (4) the provisions of this
Note and any  documents  securing  payment of this Note  shall be  automatically
reformed so that the effective  rate of interest shall be reduced to the Maximum
Rate.  For the purpose of determining  the Maximum Rate,  all interest  payments
with respect to this Note shall be amortized, prorated and spread throughout the
full term of the Note so that the effective  rate of interest on account of this
Note is uniform  throughout  the term hereof.  Borrower  agrees that the Maximum
Rate to be charged or  collected  pursuant to this Note shall be the  applicable
indicated rate ceiling as defined in TEX. REV. CIV. STAT.  ANN. Art.  5069-1.04,
provided  that  Lender  may rely on other  applicable  laws,  including  without
limitation laws of the United States, for calculation of the Maximum Rate if the
application thereof results in a greater Maximum Rate. Except as provided above,
the provisions of this Note shall be governed by the laws of the State of Texas.

         Each maker,  surety,  guarantor  and  endorser  waives  demand,  grace,
notice,  presentment for payment, notice of intention to accelerate the maturity
hereof,  notice of acceleration  of the maturity hereof and protest,  and agrees
that this Note may be  renewed,  and the time of payment  extended  from time to
time, without notice and without releasing any of the foregoing.

         Borrower may prepay this Note,  in whole or in part,  at any time prior
to maturity without penalty, and interest shall cease on any amount prepaid. Any
partial  prepayment  shall  be  applied  toward  the  payment  of the  principal
installments last maturing on the Note, that is, in inverse order of maturity.

         This Note is subject to an express  contractual  right of offset as set
forth in Section 8 of that certain  Employment  Agreement  Amendment No. 2 among
Borrower and Lender.
                                                        /s/ David S. Lawi
                                                     ---------------------------
                                                          David S. Lawi