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                                                                    Exhibit 23.8

February 6, 2003

                         CONSENT OF CANADIAN COUNSEL

      We hereby consent to the use of our name in the Registration Statement
on Form S-1 and the Registration Statement on Form S-4 (the "Registration
Statements") as counsel who has represented Grey Wolf Exploration Inc., an
Alberta corporation, in connection with the issue and sale of Abraxas'
11-1/2% Secured Notes due 2007 (including specifically the reference
contained under the caption "Enforceability of Civil Liabilities Against
Foreign Persons") and to the use of this opinion as an exhibit to the
Registration Statement.  In giving this consent, we do not hereby admit that
we are in the category of persons whose consent is required under Section 7
of the Act.

                                          Yours very truly,

                                          /s/ OSLER, HOSKIN & HARCOURT LLP