1
                                                                    EXHIBIT 23.6


           CONSENT OF INDEPENDENT PETROLEUM ENGINEERS AND GEOLOGISTS

     We hereby consent to the incorporation by reference in this Amendment 
No. 2 to the Registration Statement on Form S-3 of our reserve report dated as
of June 30, 1997, and to all references to our firm appearing in the First
Amendment to the Annual Report on Form 10-K/A of DeepTech International Inc. for
the fiscal year ended June 30, 1997 incorporated by reference in this Amendment
No. 2 to Form S-3. We also consent to the reference to us under the heading
"Experts" in this Amendment No. 2 to Form S-3.

                               NETHERLAND, SEWELL & ASSOCIATES, INC.

                                              
                               By: /s/ FREDERIC D. SEWELL
                                  ----------------------------
                                  Frederic D. Sewell
                                  President

Dallas, Texas
   
March 3, 1999