Department of the Gulf north. On November 3, 1863, the northern boundary was extended to latitude 33° north. On July 25, 1863, the department/district was transferred to the Department of Mississippi and Eastern Louisiana. It remained in that department only until January 28, 1864, when it was transferred to the Department of Alabama and Eastern Mississippi. Upon being transferred, the department/district boundaries were redefined as beginning at the mouth of the Pearl River, running north to latitude 32° north, east to the Georgia State line and south to the Gulf of Mexico. On May 8, 1864, the boundary was again modified to define the
Gulf of Mexico origin for the Gulf of Mexico at the close of the Permian, which could have caused the Permian–Triassic extinction event. However, Gulf Coast geologists do not regard this hypothesis as having any credibility. Instead they overwhelmingly accept plate tectonics, not an asteroid impact, as having created the Gulf of Mexico as illustrated by papers authored by Kevin Mickus and others. This hypothesis is not to be confused with the Chicxulub Crater, a large impact crater on the coast of the Gulf of Mexico on the Yucatán Peninsula. Increasingly, the Gulf of Mexico is regarded as a backarc basin behind the