Petroleum geologists attending an international symposium here have discounted speculation in Japan and the West that China's offshore crude oil potential could rival that of the Middle East.

The petroleum reserves of the People's Republic instead are probably more comparable to those of the Alaskan north slope, according to papers presented at the second circum-pacific energy and minerals resources conference.

The six-day meeting concluded Aug. 4, drawing more than 725 delegates from 38 countries. About 200 of those attending were from countries other than the United States including several European and Middle East nations.

Estimates on China's crude oil reserves have varied widely in recent years. The most optimistic projections emerging at the Honolulu conference placed estimated ultimate recovery at 70 billion barrels, compared with an estimated 450 billion barrels of known reserves for the United States.

Making the 70 billion barrell projection was A. A. Meyerhoff, consulting geologist from Tulsa. He said present evidence suggest that China may recover 40 billion barrels of crude from onshore wells and another 30 billion from offshore sites.

At present, 98.4 percent of all oil production in China occurs from onshore wells, according to Meyerhoff. The Chinese are showing considerable interest, however, moving offshore, and are encouraging visits from Westerners with expertise in offshore exploration.

China's policy problem, according to Meyerhoff, is that the most likely sites for future onshore production are located away from major population and industral centers, notably those in the southern parts of the country.

China will have to engage in a fundamental policy shift and seek offshore oil near its heavily populated sectors if it hopes to meet oil production goals to build a significant industrial base, he said.

Meyerhoff said that moving offshore could pose future political problems, noting that China's official government maps claim all deepwater areas of the East and South China Seas to the 200-meter lines of waters of the Philippines, Malaysia, Brunei and Vietnam.

He rated the crude oil potential for offshore areas like this: South China Sea west of Taiwan - good; Tonkin Gulf - good; East China Sea - good; Yellow Sea - Very good.

Conference chairman Michel T. Halbouty, a Houston petroleum consultant, said an invitation to the People's Republic to attend the Honolulu meeting was delivered to a Chinese scientist personally by George Bush, United States chief diplomat in Peking.

China sent its regrets, making no mention of the presence of a delegation from Taiwan.Also absent was the Soviet Union, which sent representatives to the first conference held in Honolulu four years ago.

The Soviet Union had agreed to attend but then declined, saying that "because of political considerations it was considered inappropriate," reported a member of the conference leadership.

Another geologist who believes the broad expectations for China's petroleum potential are starting to shrink is Maurice J. Terman, with the U.S. Geological survey.

Nonetheless he said he forsees "the start of a very productive exploratory period, especially in the offshore areas."

Terman, who was born in China to educational missionary parents, said talks have been under way for some time for an exchange of geology scientists.

"I think the Chinese can teach us a great deal about onshore exploration, and we probably have something that's useful to them on offshore exploration," he said.

"The Chinese certainly have the widest experience of anyone in the world at the moment with onshore drilling. Their largest producing field is at Ta-Ch'ing (in Heilungkiang Province), where they've sunk more than 4,000 wells.

"The exploration and development of the Ta-Ch'ing field is a model that the development of other continental basins could be based on."