An iceberg about the size of Luxembourg that struck a glacier off Antarctica and dislodged another massive block of ice could lower the levels of oxygen in the world's oceans, Australian and French scientists said Friday....

The new iceberg is 48 miles long and about 24 miles wide and holds roughly the equivalent of a fifth of the world's annual total water usage, Young told The Associated Press....

The icebergs, weighing 860 billion tons and 700 billion tons respectively, are located in water over the Antarctic Continental Shelf, Young said....