EXHIBIT 99.1


                                  NEWS RELEASE

                                                               Company Contacts:
                                       Investors: Frank Hopkins or Chris Paulsen
                                      Media and Public Affairs:   Susan Spratlen
                                                                  (972) 444-9001

         Pioneer Announces Sale of Argentina Operations for $675 Million

Dallas,  Texas, January 17, 2006 -- Pioneer Natural Resources Company (NYSE:PXD)
announced  today that the Company has entered into a purchase and sale agreement
with  Apache  Corporation  (NYSE:APA)  to sell all of  Pioneer's  operations  in
Argentina for cash proceeds of  approximately  $675  million.  The  transaction,
which broadens  Pioneer's  previously  announced plan to divest its non-operated
Tierra del Fuego assets in southern  Argentina,  is expected to close during the
first  quarter or early second  quarter.  The  agreement is subject to customary
closing conditions.

Pioneer  expects  to  utilize  the  proceeds  from  the  divestiture  to  reduce
short-term debt.

Production  from the Argentina  assets was  approximately  32,500 barrels of oil
equivalent per day during 2005 and was expected to contribute a similar level in
2006. As of January 1, 2006, the  properties' net proved reserves were estimated
to be approximately 101 million barrels of oil equivalent.

"The sale of our Argentina  assets is consistent with the strategic  initiatives
announced last September to deliver  enhanced value to our  shareholders,"  said
Scott D. Sheffield, Chairman and CEO. "It will allow us to reallocate capital to
high-return North America development opportunities."

Pioneer is a large  independent oil and gas exploration and production  company,
headquartered  in  Dallas,  with  operations  in the United  States,  Canada and
Africa. For more information, visit Pioneer's website at www.pioneernrc.com

Except for historical  information contained herein, the statements in this News
Release are forward-looking statements that are made pursuant to the Safe Harbor
Provisions   of  the  Private   Securities   Litigation   Reform  Act  of  1995.
Forward-looking  statements and the business prospects of Pioneer are subject to
a number of risks and uncertainties  which may cause Pioneer's actual results in
future periods to differ materially from the forward-looking  statements.  These
risks and uncertainties include,  among other things,  volatility of oil and gas
prices, product supply and demand,  government regulation or action, third party
approvals,  international  operations and associated international political and
economic  instability,  litigation,  the  costs  and  results  of  drilling  and
operations,  availability of drilling equipment,  Pioneer's ability to implement
its business plans or complete its development projects as scheduled,  access to
and cost of capital,  uncertainties  about  estimates  of  reserves,  quality of
technical data, environmental and weather risks, acts of war or terrorism. These
and other  risks are  described  in  Pioneer's  10-K and 10-Q  Reports and other
filings with the Securities and Exchange Commission.