Experts had predicted that B15A -- an iceberg 100 miles (160 kilometers) long -- would likely slam into a huge glacier near the U.S. McMurdo Research Station in Antarctica some time last weekend, but the iceberg appeared to have run aground about three miles (5 kilometers) from the glacier, known as the Drygalski Ice Tongue, Antarctica New Zealand's science strategy manager, Dean Peterson, said Thursday.

"This berg has wedged itself between two shallow areas. ... It really hasn't gotten any closer for a week now," Peterson said. "It's kind of shimmying back and forth now ... so I don't know whether it's ever going to get to the Drygalski or not."

The apparent grounding of the 1,200-square-mile iceberg could present problems to scientific bases on the frozen continent.

B15A has blocked wind and water currents that break up ice floes in McMurdo Sound during the Antarctic summer, causing a build-up of ice behind it. The U.S. McMurdo Station and New Zealand's Scott Base are located on the sound, and Italy's Terra Nova base is nearby.

The iceberg and the ice buildup are in the path of ships due to arrive in Antarctica soon with fuel and food for the three stations. Officials say the bases are not immediately in danger of running out of supplies, and scientists are looking into solutions, including breaking a path through the ice.