A bill to amend the Internal Revenue Code of 1954 to provide that the percentage depletion method may be used only for oil and gas wells located in the United States or adjacent to the North American continent.

Provides, under the Internal Revenue Code, that the percentage depletion method may be used only for oil and gas wells located in the "northwestern quadrisphere" as the 50 States, the District of Columbia, Panama, Costa Rica, and any country located entirely above 10 degrees north latitude, east of 170 degrees longitude west of greenwick, and west 50 degrees longitude west of greenwich. (Amends 26 U.S.C. 613)