1 EXHIBIT 21 SUBSIDIARIES OF THE REGISTRANT NAME INCORPORATED IN - ---- --------------- Shell Energy Resources Inc.................................................... Delaware Shell Energy Company........................................................ Delaware Pecten International Company............................................. Delaware Pecten Ash Sham Company............................................. Delaware Pecten Brazil Exploration Company................................... Delaware Pecten Cameroon Company............................................. Delaware Pecten Syria Petroleum Company...................................... Delaware Shell Offshore Inc.......................................................... Delaware Shell Onshore Ventures Inc............................................... Delaware Shell Frontier Oil & Gas Inc............................................. Delaware SOI Royalties Inc........................................................ Delaware Shell Western E&P Inc....................................................... Delaware Shell Cortez Pipeline Company............................................ Delaware Shell Pipe Line Corporation................................................... Maryland Concha Chemical Pipeline Company............................................ Delaware Pecten Arabian Company........................................................ Delaware PICO Limited............................................................. Bermuda The names of other subsidiaries have been omitted because, as of December 31, 1993, such subsidiaries considered in the aggregate as a single subsidiary would not constitute a "significant subsidiary." 65