A panel of University of Texas petroleum experts will look into the lasting effects of the deepwater oil spill.

Last month, an offshore oil rig exploded and sank, affecting about 7 percent of federal waters.

The UT panel will examine the possible cause of the spill, as well as the consequences and the cost.

One expert said much of the oil hasn't even reached the surface, and the impact on deep-sea life and the coastline habitat depends on how much the spill spreads and how far it reaches.

Federal officials have already expanded the distance of the ban on fishing, due to the continual growth of the spill

The National Oceanic and Atmospheric Administration announced Tuesday that it would expand the closed area to nearly 46,000 square miles, or about 19 percent of federal waters. NOAA would not say exactly where until later in the day.

NOAA had already shut down fishing from the Mississippi River to the Florida Panhandle.

Dr. Jane Lubchenco of NOAA said the government will be testing fish that is caught to make sure it's safe.

The Associated Press contributed to this report.