What a team of underwater archeologists suspect may be the ruins of the palaces of Cleopatra and Marc Antony have been found in 20 feet of water in the eastern harbor of the ancient city of Alexandria in Egypt.

The discovery of large stone columns embedded in the mud of Alexandria harbor by divers has prompted them to say they discovered the ruins of the two places. The divers did not return any of the columns to land. Instead, they photographed the columns and presented the photographic evidence at the eighth annual Underwater Archeological Conference in Albuquerque Friday.

Bruno Crespi, a spokesman for Mobius, that besides the stone columns divers had found the remains of marble and granite statues in the harbor at a different location that he says he feels came from an ancient temple built to honor the Egyptian goddess Isis.

"Historical records dating back to 23 B.C. describe that what we have found are the ruins of the two palaces . . . and the temple of Isis," Crespi said, "We believe this is a very important find."

The underwater search, by the Los Angeles-based Mobius Group, also found materials from the Lighthouse of the Pharos, one of the wonders of the classical world, and remnants of other great structures that once lined the shores of Alexandria.

Schwartz said the discovery was "the merge tip of the iceberg in terms of what must still lie beneath" in the harbor of Alexandria, founded in 331 by Alexander the Great.

The other co-author of the paper, Mieczyslaw Rodziewicz of the University of Warsaw, said the discovery was "of the highest importance."

"I, as an archaeologist, would classify it higher than the discovery even of the tomb of Alexander the Great," Rodziewicz said.

Schwartz said the ruins were dicovered in an area which had once been above ground and constituted the shoreline of Alexandria. He said that over the centuries the area had subsided and the buildings had become covered with water.

"Despite the fact that these were enormous and well-known buildings, their whereabouts was unknown to us," he said.

Schwartz also said previous efforts to locate the buildings through more traditional efforts had been unsuccessful. One problem in searching the harbor was that the waters were so murky it was like "swimming in minerstrone soup," Schwartz said. He also said diving in the harbor was like "swimming in an open sewer" because of the discharge of sewage into the bay.

The Mobius Group began its research in November 1978 and, along with more traditional underwater search methods, requested the assistance of 11 psychics. The psychics were given maps of the harbor and asked separately to pinpoint locations of the items sought in the search.

Schwartz declined to identify the 11 psychics, all of whom he said he been tested previously and found to be at least 50 percent accurate in their predictions.

Schwartz said the responses of the psychics were then examined for areas of agreement, and searches were concentrated in those areas.

In addition to the two palaces and the lighthouse the underwater diving teams found the Temple of Isis Pharia, goddess of the Egyptian trinity. Also discovered underwater was a small stone sphinx, blocks from a large temple complex, a cluster of bead-like stones, a large crown from a statue and other objects.