Texaco Inc. said yesterday it had signed a preliminary agreement with the Soviet Union that could lead to the company's development and production of vast Soviet oil reserves.

It is the third major oil development deal the Soviets have signed recently. Another U.S. oil company, Chevron Corp., and the Soviet Union reached a similar accord three months ago.

Although the Soviet Union is the world's biggest oil producer, pumping more than 11 million barrels a day, it has had limited success in fully exploiting its oil resources. The Soviets hope the American firms can supply technology and know-how that will allow the Soviet Union to produce oil and sell it abroad to bring in badly needed hard currency.

"It's a perfect marriage," said a spokesman for Texaco, which is based in White Plains, N.Y. "The Soviets have the proven reserves. What they have said openly is they are looking for Western technology ... to get at it."

Texaco said its agreement with the Soviet Ministry of Geology covers "proposed joint participation in the exploration, development and production of hydrocarbons -- including development of areas of identified and established oil reserves."

However, despite the sweeping sound of that description, Texaco's agreement at first covers only a feasibility study of producing oil in the Timan-Pechora region, near the Arctic Circle. The region, which is believed to hold more than 5 billion barrels of oil and natural gas, is one of the largest undeveloped oil fields in the world and more than half as large as the Prudhoe Bay field in Alaska.

If the feasibility study, which is to get underway in October, indicates that production from the fields is practical, Texaco said it hopes to form a joint venture with the Soviets to pump the oil for domestic and foreign markets.

In addition, the agreement would allow Texaco eventually to extend its interests in the Soviet Union into other oil-producing areas. The agreement only covers onshore production, which is controlled by the Ministry of Geology. Another Soviet agency is responsible for offshore petroleum exploration and production.

In May, the Soviets granted San Francisco-based Chevron exclusive rights to explore and develop a huge, newly discovered oil field near the Caspian Sea. That field is believed to hold between 20 billion and 25 billion barrels of oil. Like the Texaco agreement, the accord with Chevron is preliminary and highly conditional.

The Soviets also have entered into a preliminary oil production agreement with a major French oil firm, Elf-Aquitaine.

Analysts said the Soviets, by moving toward joint production deals with foreign companies, apparently are admitting that they are unable to develop their oil resources themselves.

"They're looking for quite a bit of help ... particularly on the technical side," said Lawrence J. Goldstein, president of the Petroleum Industry Research Foundation, a New York think tank partly funded by the oil industry. "The enthusiasm has been very strong."