Plans by the Saudi Arabian Oil Co. to buy half of Texaco Inc.'s refining and marketing assets could further erode the domestic oil industry and increase reliance on foreign supplies, Rep. John Bryant said Friday in asking the treasury secretary to investigate the proposed deal. ``The enormity of this acquisition causes us to believe a second look should be taken at the matter, because of its possible impact on the domestic oil and gas industry and on our ability to become energy independent,'' Bryant said. Bryant, a Dallas Democrat, Sen. Howard Metzenbaum, D-Ohio, Sen. Jeff Bingamon, D-N.M., and Rep. Edward Markey, D-Mass., appealed to Treasury Secretary Nicholas F. Brady to investigate the joint venture, named Star Enterprises, on national security grounds. The Saudi-Texaco deal, announced Nov. 10, would include three refineries, 50 distribution terminals, 1,400 service stations and 10,000 franchised gasoline stations in 23 Eastern and Gulf Coast states. In their letter, the Democrats said they believe the acquisition falls under the law enabling the government to block mergers involving a foreign interests if there is evidence that national security is threatened. The acquisition, they wrote, could ``seriously increase U.S. dependence on foreign oil, threaten the viability of the domestic oil industry and jeopardize the well-being of American consumers.'' ``The lessons of the 1973-74 oil embargo and the 1978-79 shortage taught our country all too well the economic and political consequences of reliance on vulnerable oil supplies,'' the letter said. ``What is particulary noteworthy is that 96 percent of the capacity of the three refineries will be used in refining Saudi Arabian crude oil,'' Bryant said. ``So you've got a circumstance that Saudi Arabia has guaranteed itself an outlet for crude oil into the American market, giving them the option of lowering crude prices while earning increased prices at the gasoline marketing level. This could amount to an enormous loss to domestic producers and leave us even more dependent on foreigh oil.'' Also, he said, foreign countries are immune from our antitrust laws, ``so it's not clear we could enforce antitrust laws against this merged entity if needed to do so to protect consumers from market manipulation.'' He said Saudi Arabia has announced a concerted effort to expand its dominance in U.S. oil markets and that its goal is to become the 10th largest seller of gasoline in the United States as a first step.