COCODRIE, La. — Oil gushed into the Gulf of Mexico unabated Saturday, and officials conveyed little hope that the flow could be contained soon, forcing towns along the Gulf Coast to brace for what is increasingly understood to be an imminent environmental disaster.

The spill, emanating from a pipe 50 miles offshore and 5,000 feet underwater, was creeping into Louisiana’s fragile coastal wetlands as strong winds and rough waters hampered cleanup efforts. Officials said the oil could hit the shores of Mississippi and Alabama as soon as Monday.

On Friday, as the first oil oozed ashore in Louisiana and the first birds were cleaned by volunteers, BP marked the end of another week of failing to shut off the source of the spill. Meanwhile, investigations into the cause of the explosion and fire continue. Here is a primer on what has gone wrong:

National Incidents - fires

via Prof B