Vice President Al Gore is coming under increasing scrutiny and criticism from enviros and others because of his cozy ties to Occidental Petroleum. Gore — who owns as much as $500,000 worth of Occidental stock and has earned about $450,000 since 1974 from a zinc-mining deal that the company helped set up — last week argued that there is nothing improper about his relationship to the company. Occidental gave $50,000 to the Democratic Party for the 1996 campaign after a telephone solicitation by Gore from his White House office and another $100,000 after its chief executive spent two nights in the Lincoln Bedroom in 1996. The Clinton administration in 1998 helped Occidental increase its oil reserves by accepting its bid for a huge California oil field previously set aside for the Navy.